fill gaps in env templates

This reverts commit c4086c8072.

README.md

@@ -1 +1,244 @@
-# group-2-threaded-project-petshop
+# PetShop
+
+A pet store management application with a Spring Boot API serving three clients: a Next.js web app, a JavaFX desktop app, and an Android app.
+
+Handles product sales, pet adoption, appointment booking, real-time chat, AI assistance, payments (Stripe), email notifications (Resend), and file storage (Azure Blob).
+
+## Tech Stack
+
+| Layer | Technology |
+|-------|------------|
+| API | Java 25, Spring Boot 4, Spring Security (JWT), Hibernate |
+| Database | MySQL 8.0, Flyway migrations |
+| Web | Next.js 16, React 19, Tailwind CSS 4 |
+| Desktop | JavaFX, Maven |
+| Android | Kotlin, Hilt, Retrofit, CameraX |
+| Infra | Docker, Azure Container Apps |
+
+## Project Structure
+
+```
+main/
+  backend/      Spring Boot REST API
+  web/          Next.js frontend
+  desktop/      JavaFX desktop client
+  android/      Android mobile app
+```
+
+## Prerequisites
+
+- Java 25
+- Node.js 18+
+- Docker
+- Maven
+- Android Studio (for mobile)
+
+## Getting Started
+
+### 1. Start the database
+
+```sh
+cd backend
+docker compose -f docker-compose.dev.yml up -d
+```
+
+### 2. Configure the backend
+
+```sh
+cd backend
+cp .env.example .env
+```
+
+Fill in `.env` with your keys:
+
+```
+JWT_SECRET=<openssl rand -base64 32>
+STRIPE_SECRET_KEY=sk_test_...
+OPENROUTER_API_KEY=sk-or-v1-...
+RESEND_API_KEY=re_...
+RESEND_FROM=PetShop <no-reply@yourdomain.com>
+```
+
+### 3. Run the backend
+
+```sh
+cd backend
+mvn spring-boot:run
+```
+
+The API starts at `http://localhost:8080`. Flyway runs migrations and seeds data automatically on first boot.
+
+### 4. Run the web frontend
+
+```sh
+cd web
+cp .env.example .env.local
+npm install
+npm run dev
+```
+
+The web app starts at `http://localhost:3000`.
+
+### 5. Run the desktop client
+
+```sh
+cd desktop
+cp connectionpetstore.properties.example connectionpetstore.properties
+mvn javafx:run
+```
+
+### 6. Run the Android app
+
+Open `android/` in Android Studio and run on an emulator or device.
+
+## Switching Between Azure and Local Backend
+
+Each client reads the backend URL from a config file. To point a client at the
+hosted Azure backend versus a local one, flip the commented lines.
+
+### Web
+
+Edit `web/.env.local`:
+
+```
+# Local
+BACKEND_URL=http://localhost:8080
+#BACKEND_URL=https://petshop-backend.nicepond-c7280126.westus2.azurecontainerapps.io
+
+# Azure
+#BACKEND_URL=http://localhost:8080
+BACKEND_URL=https://petshop-backend.nicepond-c7280126.westus2.azurecontainerapps.io
+```
+
+Restart the dev server after changing.
+
+### Desktop
+
+Edit `desktop/src/main/resources/connectionpetstore.properties`:
+
+```
+# Local
+api.baseUrl=http://localhost:8080
+#api.baseUrl=https://petshop-backend.nicepond-c7280126.westus2.azurecontainerapps.io
+
+# Azure
+#api.baseUrl=http://localhost:8080
+api.baseUrl=https://petshop-backend.nicepond-c7280126.westus2.azurecontainerapps.io
+```
+
+### Android
+
+Edit `android/local.properties`:
+
+```properties
+# Local (emulator — 10.0.2.2 maps to host's localhost)
+petstore.backend.emulatorUrl=http\://10.0.2.2\:8080/
+petstore.backend.deviceUrl=http\://192.168.x.x\:8080/
+
+# Azure
+petstore.backend.emulatorUrl=https\://petshop-backend.nicepond-c7280126.westus2.azurecontainerapps.io/
+petstore.backend.deviceUrl=https\://petshop-backend.nicepond-c7280126.westus2.azurecontainerapps.io/
+```
+
+Sync Gradle and re-run the app.
+
+## API
+
+A Postman collection is available at `backend/postman/`. Key endpoint groups:
+
+- `/api/auth` -- registration, login, password reset
+- `/api/products` -- catalog and inventory
+- `/api/pets` -- listings and adoption
+- `/api/appointments` -- booking
+- `/api/cart`, `/api/sales`, `/api/refunds` -- transactions
+- `/api/chat` -- messaging and AI assistant
+- `/ws` -- WebSocket (STOMP) for real-time updates
+
+## Docker (full stack)
+
+```sh
+cd backend
+docker compose up --build -d
+```
+
+Starts the API and MySQL together. The web frontend has its own Dockerfile for independent deployment.
+
+## Running the Web App
+
+Requires Node.js 18+.
+
+```sh
+cd web
+cp .env.example .env.local
+npm install
+npm run dev
+```
+
+Open `http://localhost:3000`. The app proxies API calls to the backend at `http://localhost:8080` by default.
+
+To point at a different backend, edit `BACKEND_URL` and `NEXT_PUBLIC_BACKEND_URL` in `.env.local`.
+
+For a production build:
+
+```sh
+npm run build
+npm run start
+```
+
+## Running the Desktop App (JavaFX)
+
+Requires IntelliJ IDEA and Java 25+.
+
+1. Open the `desktop/` directory in IntelliJ.
+2. Copy `connectionpetstore.properties.example` to `connectionpetstore.properties` and edit it to match your database. The defaults expect the dev Docker database:
+
+```
+url=jdbc:mysql://127.0.0.1:3306/Petstoredb?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC
+user=petshop
+password=petshop
+```
+
+3. Open **View > Tool Windows > Maven** and click **Reload All Maven Projects**.
+4. Expand **Plugins > javafx** and double-click **javafx:run**.
+
+Default accounts seeded on first run:
+
+| Role | Username | Password |
+|------|----------|----------|
+| Admin | `admin` | `admin123` |
+| Staff | `staff` | `staff123` |
+
+## Running the Android App
+
+Requires Android Studio and the Android SDK (min API 24).
+
+1. Copy `local.properties.template` to `local.properties` and set `sdk.dir` to your Android SDK path.
+2. Configure the backend URLs in `local.properties`:
+
+```properties
+# Emulator — 10.0.2.2 maps to the host machine's localhost
+petstore.backend.emulatorUrl=http\://10.0.2.2\:8080/
+
+# Physical device — use the host machine's LAN IP
+petstore.backend.deviceUrl=http\://192.168.x.x\:8080/
+```
+
+3. Open the `android/` directory in Android Studio.
+4. Sync Gradle, then run on an emulator or connected device.
+
+## Running the Backend
+
+Requires IntelliJ IDEA and Java 25+.
+
+1. Open the `backend/` directory in IntelliJ.
+2. Copy `.env.example` to `.env` and fill in your API keys.
+3. Start the database using Docker from IntelliJ's **Services** panel, or from a terminal:
+
+```sh
+cd backend
+docker compose -f docker-compose.dev.yml up -d
+```
+
+4. Run the `BackendApplication` main class from IntelliJ.
+
+The API starts at `http://localhost:8080`. Flyway runs migrations and seeds data automatically on first boot.

android/app/src/main/java/com/example/petstoremobile/PetStoreApplication.java

@@ -1,3 +1,9 @@
+/*
+ * Application entry point, sets up Hilt dependency injection.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
 package com.example.petstoremobile;
 
 import android.app.Application;

android/app/src/main/java/com/example/petstoremobile/activities/ForgotPasswordActivity.java

@@ -1,3 +1,9 @@
+/*
+ * Screen where the user can request a password reset email.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
 package com.example.petstoremobile.activities;
 
 import android.os.Bundle;
@@ -32,6 +38,9 @@ public class ForgotPasswordActivity extends AppCompatActivity {
 
     private ActivityForgotPasswordBinding binding;
 
+    /**
+     * Set the content view for forget password page
+     */
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         EdgeToEdge.enable(this);
@@ -54,6 +63,10 @@ public class ForgotPasswordActivity extends AppCompatActivity {
         binding.btnBackToLogin.setOnClickListener(v -> finish());
     }
 
+    /**
+     * A function to send a reset link to the given email address.
+     * Calls the forgotPassword endpoint. To send the reset link
+     * */
     private void sendResetLink(String email) {
         binding.btnSubmit.setEnabled(false);
 

android/app/src/main/java/com/example/petstoremobile/activities/HomeActivity.java

@@ -1,7 +1,16 @@
+/*
+ * Main home screen that shows the dashboard after the user logs in.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
 package com.example.petstoremobile.activities;
 
 import android.Manifest;
+import android.content.BroadcastReceiver;
+import android.content.Context;
 import android.content.Intent;
+import android.content.IntentFilter;
 import android.content.pm.PackageManager;
 import android.os.Build;
 import android.os.Bundle;
@@ -20,6 +29,7 @@ import androidx.navigation.fragment.NavHostFragment;
 import androidx.navigation.ui.NavigationUI;
 
 import com.example.petstoremobile.R;
+import com.example.petstoremobile.api.auth.TokenManager;
 import com.example.petstoremobile.databinding.ActivityHomeBinding;
 import com.example.petstoremobile.services.ChatNotificationService;
 
@@ -30,6 +40,16 @@ public class HomeActivity extends AppCompatActivity {
     private ActivityHomeBinding binding;
     private NavController navController;
 
+    private final BroadcastReceiver forceLogoutReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            Intent loginIntent = new Intent(HomeActivity.this, MainActivity.class);
+            loginIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
+            startActivity(loginIntent);
+            finish();
+        }
+    };
+
     // Launcher to ask for notification permission
     private final ActivityResultLauncher<String> requestPermissionLauncher =
             registerForActivityResult(new ActivityResultContracts.RequestPermission(), isGranted -> {
@@ -67,18 +87,30 @@ public class HomeActivity extends AppCompatActivity {
             handleIntent(getIntent());
         }
 
-        // Start the notification service and request for notification permission
+        IntentFilter filter = new IntentFilter(TokenManager.ACTION_FORCE_LOGOUT);
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            registerReceiver(forceLogoutReceiver, filter, Context.RECEIVER_NOT_EXPORTED);
+        } else {
+            registerReceiver(forceLogoutReceiver, filter);
+        }
+
         startNotificationService();
         requestNotificationPermission();
     }
 
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        unregisterReceiver(forceLogoutReceiver);
+    }
+    
     /**
      * Handles new intents received while the activity is already running (like notifications).
      */
     @Override
     protected void onNewIntent(Intent intent) {
         super.onNewIntent(intent);
-        setIntent(intent); // Set the new intent so fragments can access updated extras
+        setIntent(intent);
         handleIntent(intent);
     }
 
@@ -103,7 +135,7 @@ public class HomeActivity extends AppCompatActivity {
     }
 
     /**
-     * Requests POST_NOTIFICATIONS permission from the user if running on Android 13 and above.
+     * Requests for notification permission from the user if running on Android 13 and above.
      */
     private void requestNotificationPermission() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {

android/app/src/main/java/com/example/petstoremobile/activities/MainActivity.java

@@ -1,3 +1,9 @@
+/*
+ * Entry point of the app that shows the login and registration screen.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
 package com.example.petstoremobile.activities;
 
 import android.content.Intent;
@@ -98,7 +104,7 @@ public class MainActivity extends AppCompatActivity {
     }
 
     /**
-     * Executes the login process using the AuthViewModel and handles the authentication response.
+     * Perform login process using the AuthViewModel and handles the authentication response.
      */
     private void performLogin(String username, String password) {
         viewModel.login(username, password).observe(this, resource -> {
@@ -112,6 +118,7 @@ public class MainActivity extends AppCompatActivity {
                 case SUCCESS:
                     if (resource.data != null) {
                         String role = resource.data.getRole();
+                        //Check if role is staff/admin or customer
                         if ("CUSTOMER".equalsIgnoreCase(role)) {
                             UIUtils.setViewsEnabled(true, binding.btnLogin);
                             binding.tvLoginStatus.setText("Customers are not allowed to log in");
@@ -132,7 +139,7 @@ public class MainActivity extends AppCompatActivity {
     }
 
     /**
-     * Retrieves the logged-in user's profile information to save their ID before navigating to the home screen.
+     * Retrieves the user's profile information to save their ID before navigating to the home screen.
      */
     private void fetchUserIdAndNavigate() {
         viewModel.getMe().observe(this, resource -> {

android/app/src/main/java/com/example/petstoremobile/adapters/ActivityLogAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying activity log entries in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -25,10 +32,16 @@ public class ActivityLogAdapter extends RecyclerView.Adapter<ActivityLogAdapter.
 
     private final List<ActivityLogDTO> items;
 
+    /**
+     * Constructor for the ActivityLogAdapter.
+     */
     public ActivityLogAdapter(List<ActivityLogDTO> items) {
         this.items = items;
     }
 
+    /**
+     * Inflates the layout for an activity log item and creates a new ViewHolder.
+     */
     @NonNull
     @Override
     public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -37,6 +50,9 @@ public class ActivityLogAdapter extends RecyclerView.Adapter<ActivityLogAdapter.
         return new ViewHolder(view);
     }
 
+    /**
+     * Binds the data from ActivityLogDTO to the items in the ViewHolder.
+     */
     @Override
     public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
         ActivityLogDTO log = items.get(position);
@@ -71,9 +87,15 @@ public class ActivityLogAdapter extends RecyclerView.Adapter<ActivityLogAdapter.
         holder.tvTimestamp.setText(formatTimestamp(log.getLogTimestamp()));
     }
 
+    /**
+     * Returns the total number of items in the list.
+     */
     @Override
     public int getItemCount() { return items.size(); }
 
+    /**
+     * Formats the timestamp string from the API to a readable date/time format.
+     */
     private String formatTimestamp(String raw) {
         if (raw == null) return "";
         try {
@@ -85,6 +107,9 @@ public class ActivityLogAdapter extends RecyclerView.Adapter<ActivityLogAdapter.
         }
     }
 
+    /**
+     * Format the Role string to be consistent
+     */
     private String formatRole(String role) {
         if (role == null) return "";
         switch (role.toUpperCase(Locale.ROOT)) {
@@ -95,6 +120,9 @@ public class ActivityLogAdapter extends RecyclerView.Adapter<ActivityLogAdapter.
         }
     }
 
+    /**
+     * Returns the first non-null and non-blank string from the provided arguments.
+     */
     private String firstNonBlank(String... values) {
         for (String v : values) {
             if (v != null && !v.isBlank()) return v;
@@ -102,9 +130,15 @@ public class ActivityLogAdapter extends RecyclerView.Adapter<ActivityLogAdapter.
         return "";
     }
 
+    /**
+     * ViewHolder class that holds references to the UI components for an activity log item.
+     */
     public static class ViewHolder extends RecyclerView.ViewHolder {
         TextView tvActivity, tvTechnical, tvUser, tvMeta, tvTimestamp;
 
+        /**
+         * Initializes the ViewHolder by finding the views within the item layout.
+         */
         public ViewHolder(@NonNull View itemView) {
             super(itemView);
             tvActivity  = itemView.findViewById(R.id.tvLogActivity);

android/app/src/main/java/com/example/petstoremobile/adapters/AdoptionAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing adoption records in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.graphics.Color;
@@ -23,6 +30,9 @@ public class AdoptionAdapter extends RecyclerView.Adapter<AdoptionAdapter.Adopti
         void onSelectionChanged(int count);
     }
 
+    /**
+     * Constructor for AdoptionAdapter.
+     */
     public AdoptionAdapter(List<AdoptionDTO> adoptionList, OnAdoptionClickListener listener) {
         this.adoptionList = adoptionList;
         this.listener = listener;
@@ -39,11 +49,17 @@ public class AdoptionAdapter extends RecyclerView.Adapter<AdoptionAdapter.Adopti
         });
     }
 
+    /**
+     * Returns a list of IDs for the currently selected adoption items.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Resets the selection state, deselecting all items.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
@@ -58,6 +74,9 @@ public class AdoptionAdapter extends RecyclerView.Adapter<AdoptionAdapter.Adopti
         }
     }
 
+    /**
+     * Inflates the layout for an adoption item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public AdoptionViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -65,6 +84,9 @@ public class AdoptionAdapter extends RecyclerView.Adapter<AdoptionAdapter.Adopti
         return new AdoptionViewHolder(binding);
     }
 
+    /**
+     * Binds adoption data to the UI components and handles click/long-click logic.
+     */
     @Override
     public void onBindViewHolder(@NonNull AdoptionViewHolder holder, int position) {
         AdoptionDTO a = adoptionList.get(position);
@@ -123,6 +145,9 @@ public class AdoptionAdapter extends RecyclerView.Adapter<AdoptionAdapter.Adopti
         });
     }
 
+    /**
+     * Returns the total number of adoption items in the list.
+     */
     @Override
     public int getItemCount() { return adoptionList.size(); }
 }

android/app/src/main/java/com/example/petstoremobile/adapters/AppointmentAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing appointments in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.graphics.Color;
@@ -23,6 +30,9 @@ public class AppointmentAdapter extends RecyclerView.Adapter<AppointmentAdapter.
         void onSelectionChanged(int count);
     }
 
+    /**
+     * Constructor for AppointmentAdapter.
+     */
     public AppointmentAdapter(List<AppointmentDTO> appointmentList,
                               OnAppointmentClickListener appointmentClickListener) {
         this.appointmentList = appointmentList;
@@ -40,25 +50,40 @@ public class AppointmentAdapter extends RecyclerView.Adapter<AppointmentAdapter.
         });
     }
 
+    /**
+     * Returns a list of IDs for the currently selected appointment items.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Resets the selection state, deselecting all items.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
     }
 
+    /**
+     * ViewHolder class that holds references to the UI components for an appointment item.
+     */
     public static class AppointmentViewHolder extends RecyclerView.ViewHolder {
         private final ItemAppointmentBinding binding;
 
+        /**
+         * Initializes the ViewHolder by finding the views within the item layout.
+         */
         public AppointmentViewHolder(@NonNull ItemAppointmentBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for an appointment item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public AppointmentViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -66,6 +91,9 @@ public class AppointmentAdapter extends RecyclerView.Adapter<AppointmentAdapter.
         return new AppointmentViewHolder(binding);
     }
 
+    /**
+     * Binds appointment data to the UI components and handles click/long-click logic.
+     */
     @Override
     public void onBindViewHolder(@NonNull AppointmentViewHolder holder, int position) {
         AppointmentDTO a = appointmentList.get(position);
@@ -124,6 +152,9 @@ public class AppointmentAdapter extends RecyclerView.Adapter<AppointmentAdapter.
         });
     }
 
+    /**
+     * Returns the total number of appointment items in the list.
+     */
     @Override
     public int getItemCount() {
         return appointmentList.size();

android/app/src/main/java/com/example/petstoremobile/adapters/BlackTextArrayAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Custom array adapter that displays items with black text.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.content.Context;
@@ -12,6 +19,7 @@ import com.example.petstoremobile.R;
 import java.util.List;
 
 // A class that overrides the arrayAdapter so the text color changes based on theme
+// Used to make spinners have black text on white background no matter the theme
 public class BlackTextArrayAdapter<T> extends ArrayAdapter<T> {
     public BlackTextArrayAdapter(@NonNull Context context, int resource, @NonNull T[] objects) {
         super(context, resource, objects);

android/app/src/main/java/com/example/petstoremobile/adapters/ChatAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying chat conversations in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -20,11 +27,17 @@ public class ChatAdapter extends RecyclerView.Adapter<ChatAdapter.ChatViewHolder
         void onChatClick(Chat chat);
     }
 
+    /**
+     * Constructor for ChatAdapter.
+     */
     public ChatAdapter(List<Chat> chatList, OnChatClickListener listener) {
         this.chatList = chatList;
         this.listener = listener;
     }
 
+    /**
+     * Inflates the layout for a chat item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public ChatViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -32,6 +45,9 @@ public class ChatAdapter extends RecyclerView.Adapter<ChatAdapter.ChatViewHolder
         return new ChatViewHolder(binding);
     }
 
+    /**
+     * Binds chat data to the UI components for a specific conversation.
+     */
     @Override
     public void onBindViewHolder(@NonNull ChatViewHolder holder, int position) {
         Chat chat = chatList.get(position);
@@ -40,14 +56,23 @@ public class ChatAdapter extends RecyclerView.Adapter<ChatAdapter.ChatViewHolder
         holder.itemView.setOnClickListener(v -> listener.onChatClick(chat));
     }
 
+    /**
+     * Returns the total number of chat items in the list.
+     */
     @Override
     public int getItemCount() {
         return chatList.size();
     }
 
+    /**
+     * ViewHolder class that holds references to the UI components for a chat item.
+     */
     public static class ChatViewHolder extends RecyclerView.ViewHolder {
         final ItemChatBinding binding;
 
+        /**
+         * Initializes the ViewHolder with the chat item's view binding.
+         */
         public ChatViewHolder(@NonNull ItemChatBinding binding) {
             super(binding.getRoot());
             this.binding = binding;

android/app/src/main/java/com/example/petstoremobile/adapters/CouponAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing coupons in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -30,11 +37,17 @@ public class CouponAdapter extends RecyclerView.Adapter<CouponAdapter.ViewHolder
         void onSelectionChanged(int count);
     }
 
+    /**
+     * Constructor for CouponAdapter.
+     */
     public CouponAdapter(List<CouponDTO> coupons, OnCouponClickListener listener) {
         this.coupons = coupons;
         this.listener = listener;
     }
 
+    /**
+     * Inflates the layout for a coupon item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -42,6 +55,9 @@ public class CouponAdapter extends RecyclerView.Adapter<CouponAdapter.ViewHolder
         return new ViewHolder(view);
     }
 
+    /**
+     * Binds coupon data to the UI components and handles interaction logic.
+     */
     @Override
     public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
         CouponDTO coupon = coupons.get(position);
@@ -95,6 +111,9 @@ public class CouponAdapter extends RecyclerView.Adapter<CouponAdapter.ViewHolder
         holder.cbSelectCoupon.setOnClickListener(v -> toggleSelection(coupon.getCouponId()));
     }
 
+    /**
+     * Toggles the selection state of a specific coupon by its ID.
+     */
     private void toggleSelection(Long id) {
         if (selectedIds.contains(id)) {
             selectedIds.remove(id);
@@ -105,6 +124,9 @@ public class CouponAdapter extends RecyclerView.Adapter<CouponAdapter.ViewHolder
         listener.onSelectionChanged(selectedIds.size());
     }
 
+    /**
+     * Enables or disables bulk selection mode.
+     */
     public void setSelectionMode(boolean selectionMode) {
         this.selectionMode = selectionMode;
         if (!selectionMode) selectedIds.clear();
@@ -112,10 +134,16 @@ public class CouponAdapter extends RecyclerView.Adapter<CouponAdapter.ViewHolder
         listener.onSelectionChanged(selectedIds.size());
     }
 
+    /**
+     * Returns the set of IDs for the currently selected coupons.
+     */
     public Set<Long> getSelectedIds() {
         return selectedIds;
     }
 
+    /**
+     * Returns the total number of coupons in the list.
+     */
     @Override
     public int getItemCount() {
         return coupons.size();
@@ -125,6 +153,9 @@ public class CouponAdapter extends RecyclerView.Adapter<CouponAdapter.ViewHolder
         TextView tvCouponCode, tvCouponDiscount, tvCouponMinOrder, tvCouponExpiry, tvCouponStatus;
         CheckBox cbSelectCoupon;
 
+        /**
+         * Initializes the ViewHolder by finding the views within the item layout.
+         */
         public ViewHolder(@NonNull View itemView) {
             super(itemView);
             tvCouponCode = itemView.findViewById(R.id.tvCouponCode);

android/app/src/main/java/com/example/petstoremobile/adapters/CustomerAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying customer entries in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.graphics.Color;
@@ -24,23 +31,42 @@ public class CustomerAdapter extends RecyclerView.Adapter<CustomerAdapter.Custom
         void onCustomerClick(int position);
     }
 
+    /**
+     * Constructor for CustomerAdapter.
+     */
     public CustomerAdapter(List<CustomerDTO> list, OnCustomerClickListener listener) {
         this.list = list;
         this.listener = listener;
     }
 
+    /**
+     * Sets the base URL for fetching customer profile images.
+     */
     public void setBaseUrl(String baseUrl) { this.baseUrl = baseUrl; }
+
+    /**
+     * Sets the authentication token for fetching images.
+     */
     public void setToken(String token) { this.token = token; }
 
+    /**
+     * ViewHolder class for customer items.
+     */
     public static class CustomerViewHolder extends RecyclerView.ViewHolder {
         final ItemCustomerBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public CustomerViewHolder(@NonNull ItemCustomerBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for a customer item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public CustomerViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -49,6 +75,9 @@ public class CustomerAdapter extends RecyclerView.Adapter<CustomerAdapter.Custom
         return new CustomerViewHolder(binding);
     }
 
+    /**
+     * Binds customer data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull CustomerViewHolder holder, int position) {
         CustomerDTO c = list.get(position);
@@ -75,6 +104,9 @@ public class CustomerAdapter extends RecyclerView.Adapter<CustomerAdapter.Custom
         holder.itemView.setOnClickListener(v -> listener.onCustomerClick(position));
     }
 
+    /**
+     * Returns the total number of customers in the list.
+     */
     @Override
     public int getItemCount() { return list.size(); }
 }

android/app/src/main/java/com/example/petstoremobile/adapters/EmployeeAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying employee entries in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.graphics.Color;
@@ -25,28 +32,46 @@ public class EmployeeAdapter extends RecyclerView.Adapter<EmployeeAdapter.Employ
         void onEmployeeClick(int position);
     }
 
+    /**
+     * Constructor for EmployeeAdapter.
+     */
     public EmployeeAdapter(List<EmployeeDTO> list, OnEmployeeClickListener listener) {
         this.list = list;
         this.listener = listener;
     }
 
+    /**
+     * Sets the base URL for fetching employee profile images.
+     */
     public void setBaseUrl(String baseUrl) {
         this.baseUrl = baseUrl;
     }
 
+    /**
+     * Sets the authentication token for fetching images.
+     */
     public void setToken(String token) {
         this.token = token;
     }
 
+    /**
+     * ViewHolder class for employee items.
+     */
     public static class EmployeeViewHolder extends RecyclerView.ViewHolder {
         private final ItemEmployeeBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public EmployeeViewHolder(@NonNull ItemEmployeeBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for an employee item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public EmployeeViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -55,6 +80,9 @@ public class EmployeeAdapter extends RecyclerView.Adapter<EmployeeAdapter.Employ
         return new EmployeeViewHolder(binding);
     }
 
+    /**
+     * Binds employee data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull EmployeeViewHolder holder, int position) {
         EmployeeDTO e = list.get(position);
@@ -90,6 +118,9 @@ public class EmployeeAdapter extends RecyclerView.Adapter<EmployeeAdapter.Employ
         holder.itemView.setOnClickListener(v -> listener.onEmployeeClick(position));
     }
 
+    /**
+     * Returns the total number of employees in the list.
+     */
     @Override
     public int getItemCount() { return list.size(); }
 }

android/app/src/main/java/com/example/petstoremobile/adapters/InventoryAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing inventory items in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.graphics.Color;
@@ -27,6 +34,9 @@ public class InventoryAdapter extends RecyclerView.Adapter<InventoryAdapter.Inve
         void onSelectionChanged(int selectedCount);
     }
 
+    /**
+     * Constructor for InventoryAdapter.
+     */
     public InventoryAdapter(List<InventoryDTO> inventoryList, OnInventoryClickListener clickListener) {
         this.inventoryList = inventoryList;
         this.clickListener = clickListener;
@@ -43,25 +53,40 @@ public class InventoryAdapter extends RecyclerView.Adapter<InventoryAdapter.Inve
         });
     }
 
+    /**
+     * Returns a list of IDs for the currently selected inventory items.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Resets the selection state, deselecting all items.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
     }
 
+    /**
+     * ViewHolder class that holds references to the UI components for an inventory item.
+     */
     public static class InventoryViewHolder extends RecyclerView.ViewHolder {
         final ItemInventoryBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public InventoryViewHolder(@NonNull ItemInventoryBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for an inventory item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public InventoryViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -69,6 +94,9 @@ public class InventoryAdapter extends RecyclerView.Adapter<InventoryAdapter.Inve
         return new InventoryViewHolder(binding);
     }
 
+    /**
+     * Binds inventory data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull InventoryViewHolder holder, int position) {
         InventoryDTO inv = inventoryList.get(position);
@@ -84,7 +112,6 @@ public class InventoryAdapter extends RecyclerView.Adapter<InventoryAdapter.Inve
         int qty = inv.getQuantity() != null ? inv.getQuantity() : 0;
         binding.tvQuantity.setText("Stock: " + qty);
 
-        // Low stock = red, normal = green (like desktop reorder concept)
         if (qty <= 5) {
             binding.tvQuantity.setTextColor(Color.parseColor("#F44336"));
         } else {
@@ -119,6 +146,9 @@ public class InventoryAdapter extends RecyclerView.Adapter<InventoryAdapter.Inve
         });
     }
 
+    /**
+     * Returns the total number of inventory items in the list.
+     */
     @Override
     public int getItemCount() {
         return inventoryList.size();

android/app/src/main/java/com/example/petstoremobile/adapters/MessageAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying chat messages in a conversation.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -37,40 +44,64 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
     private String baseUrl;
     private OnAttachmentClickListener attachmentClickListener;
 
+    /**
+     * Constructor for MessageAdapter.
+     */
     public MessageAdapter(List<Message> messages, Long currentUserId) {
         this.messages = messages;
         this.currentUserId = currentUserId;
         setHasStableIds(true);
     }
 
+    /**
+     * Returns an ID for each message.
+     */
     @Override
     public long getItemId(int position) {
         Message m = messages.get(position);
         return m.getId() != null ? m.getId() : position;
     }
 
+    /**
+     * Updates the current user's ID and refreshes the list.
+     */
     public void setCurrentUserId(Long id) {
         this.currentUserId = id;
         notifyDataSetChanged();
     }
 
+    /**
+     * Updates the staff ID to identify staff messages in the UI.
+     */
     public void setStaffId(Long id) {
         this.staffId = id;
         notifyDataSetChanged();
     }
 
+    /**
+     * Sets the authentication token.
+     */
     public void setToken(String token) {
         this.token = token;
     }
 
+    /**
+     * Sets the base API URL.
+     */
     public void setBaseUrl(String baseUrl) {
         this.baseUrl = baseUrl;
     }
 
+    /**
+     * Sets a listener for clicks on message attachments.
+     */
     public void setOnAttachmentClickListener(OnAttachmentClickListener listener) {
         this.attachmentClickListener = listener;
     }
 
+    /**
+     * Determines if a message is 'sent' or 'received' based on the sender's ID.
+     */
     @Override
     public int getItemViewType(int position) {
         Message m = messages.get(position);
@@ -80,6 +111,9 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         return TYPE_RECEIVED;
     }
 
+    /**
+     * Inflates the chat layout for a message.
+     */
     @NonNull @Override
     public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
         LayoutInflater inf = LayoutInflater.from(parent.getContext());
@@ -92,6 +126,9 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         }
     }
 
+    /**
+     * Binds message data to the appropriate ViewHolder.
+     */
     @Override
     public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
         Message m = messages.get(position);
@@ -99,14 +136,26 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         if (holder instanceof ReceivedHolder) ((ReceivedHolder) holder).bind(m, token, baseUrl, attachmentClickListener, staffId);
     }
 
+    /**
+     * Returns the total number of messages.
+     */
     @Override public int getItemCount() { return messages.size(); }
 
+    /**
+     * ViewHolder for messages sent by the user.
+     */
     static class SentHolder extends RecyclerView.ViewHolder {
         final ItemMessageSentBinding binding;
+        /**
+         * Initializes the SentHolder with view binding.
+         */
         SentHolder(ItemMessageSentBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
+        /**
+         * Binds sent message data to the bubble UI.
+         */
         void bind(Message m, String token, String baseUrl, OnAttachmentClickListener listener) {
             binding.tvSenderName.setText("You");
             binding.tvTimestamp.setText(formatTimestamp(m.getTimestamp()));
@@ -128,12 +177,21 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         }
     }
 
+    /**
+     * ViewHolder for messages received from others.
+     */
     static class ReceivedHolder extends RecyclerView.ViewHolder {
         final ItemMessageReceivedBinding binding;
+        /**
+         * Initializes the ReceivedHolder with view binding.
+         */
         ReceivedHolder(ItemMessageReceivedBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
+        /**
+         * Binds received message data to the bubble UI.
+         */
         void bind(Message m, String token, String baseUrl, OnAttachmentClickListener listener, Long staffId) {
             binding.tvSenderName.setText(resolveSenderName(m, staffId));
             binding.tvTimestamp.setText(formatTimestamp(m.getTimestamp()));
@@ -155,6 +213,9 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         }
     }
 
+    /**
+     * Resolves the display name of the sender.
+     */
     private static String resolveSenderName(Message m, Long staffId) {
         if ("BOT".equalsIgnoreCase(m.getSenderRole())) {
             return (m.getSenderDisplayName() != null && !m.getSenderDisplayName().isEmpty())
@@ -166,6 +227,9 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         return "Customer";
     }
 
+    /**
+     * Formats the timestamp string into readable format.
+     */
     private static String formatTimestamp(String timestamp) {
         if (timestamp == null || timestamp.isEmpty()) return "";
         try {
@@ -178,8 +242,11 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
         }
     }
 
+    /**
+     * Logic for displaying an attachment in the chat.
+     */
     private static void displayAttachment(Message m, ImageView iv, TextView tvName, String token, String baseUrl) {
-        // Check if there's an attachment by looking at name or mime type
+        // Check if there's an attachment
         if (m.getAttachmentName() != null || m.getAttachmentMimeType() != null) {
             // Construct the download URL using the message ID
             String url;
@@ -187,7 +254,7 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
                 String cleanBase = baseUrl.endsWith("/") ? baseUrl.substring(0, baseUrl.length() - 1) : baseUrl;
                 url = cleanBase + "/api/v1/chat/messages/" + m.getId() + "/attachment";
             } else {
-                url = m.getAttachmentUrl(); // Fallback
+                url = m.getAttachmentUrl();
             }
 
             if (url == null) {
@@ -208,7 +275,7 @@ public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
                             .build());
                 }
 
-                // Use a signature to prevent Glide from showing stale cached images for the same URL/ID
+                // Use a signature to prevent Glide from showing cached images instead of loading new ones
                 String signatureKey = (m.getTimestamp() != null ? m.getTimestamp() : "") + m.getId();
 
                 Glide.with(iv.getContext()).clear(iv);

android/app/src/main/java/com/example/petstoremobile/adapters/PetAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing pets in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.graphics.Color;
@@ -31,7 +38,9 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> i
         void onSelectionChanged(int selectedCount);
     }
 
-    //Constructor
+    /**
+     * Constructor for PetAdapter.
+     */
     public PetAdapter(List<PetDTO> petList, OnPetClickListener petClickListener) {
         this.petList  = petList;
         this.petClickListener = petClickListener;
@@ -48,35 +57,54 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> i
         });
     }
 
+    /**
+     * Sets the base URL for fetching pet images from the server.
+     */
     public void setBaseUrl(String baseUrl) {
         this.baseUrl = baseUrl;
     }
 
+    /**
+     * Sets the authentication token
+     */
     public void setToken(String token) {
         this.token = token;
     }
 
+    /**
+     * Returns a list of IDs for the currently selected pet items.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Resets the selection state, deselecting all items.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
     }
 
-    // Get the controls of each row in recycler view
+    /**
+     * ViewHolder class that holds references to the UI components for a pet item.
+     */
     public static class PetViewHolder extends RecyclerView.ViewHolder {
         private final ItemPetBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public PetViewHolder(@NonNull ItemPetBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
-    // Create a new row view
+    /**
+     * Inflates the layout for a pet item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public PetViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -84,7 +112,9 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> i
         return new PetViewHolder(binding);
     }
 
-    //populate the row with pet data
+    /**
+     * Binds pet data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull PetViewHolder holder, int position) {
         PetDTO pet = petList.get(position);
@@ -103,7 +133,7 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> i
         
         binding.tvPetStatus.setText(pet.getPetStatus());
 
-        //Set the status color depending on availability. If available, green, If Pending, yellow, otherwise red
+        //Set the status color depending on availability
         if (pet.getPetStatus() != null) {
             switch (pet.getPetStatus()) {
                 case "Available":
@@ -157,6 +187,9 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> i
         });
     }
 
+    /**
+     * Returns the total number of pet items in the list.
+     */
     @Override
     public int getItemCount() {
         return petList.size();

android/app/src/main/java/com/example/petstoremobile/adapters/ProductAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying products in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.*;
@@ -22,28 +29,46 @@ public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductV
         void onProductClick(int position);
     }
 
+    /**
+     * Constructor for ProductAdapter.
+     */
     public ProductAdapter(List<ProductDTO> productList, OnProductClickListener listener) {
         this.productList = productList;
         this.listener = listener;
     }
 
+    /**
+     * Sets the base URL for fetching product images.
+     */
     public void setBaseUrl(String baseUrl) {
         this.baseUrl = baseUrl;
     }
 
+    /**
+     * Sets the authentication token
+     */
     public void setToken(String token) {
         this.token = token;
     }
 
+    /**
+     * ViewHolder class for product items.
+     */
     public static class ProductViewHolder extends RecyclerView.ViewHolder {
         final ItemProductBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public ProductViewHolder(@NonNull ItemProductBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for a product item and creates the ViewHolder.
+     */
     @NonNull
     @Override
     public ProductViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -51,6 +76,9 @@ public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductV
         return new ProductViewHolder(binding);
     }
 
+    /**
+     * Binds product data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull ProductViewHolder holder, int position) {
         ProductDTO p = productList.get(position);
@@ -72,6 +100,9 @@ public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductV
         holder.itemView.setOnClickListener(v -> listener.onProductClick(position));
     }
 
+    /**
+     * Returns the total number of product items in the list.
+     */
     @Override
     public int getItemCount() { return productList.size(); }
 }

android/app/src/main/java/com/example/petstoremobile/adapters/ProductSupplierAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing product-supplier links in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -25,6 +32,9 @@ public class ProductSupplierAdapter extends RecyclerView.Adapter<ProductSupplier
         void onSelectionChanged(int count);
     }
 
+    /**
+     * Constructor for ProductSupplierAdapter.
+     */
     public ProductSupplierAdapter(List<ProductSupplierDTO> list, OnProductSupplierClickListener listener) {
         this.list = list;
         this.listener = listener;
@@ -41,25 +51,40 @@ public class ProductSupplierAdapter extends RecyclerView.Adapter<ProductSupplier
         });
     }
 
+    /**
+     * Returns the list of selected keys for bulk deletion.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Clears all selected items and exits selection mode.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
     }
 
+    /**
+     * ViewHolder for Product-Supplier relationship items.
+     */
     public static class PSViewHolder extends RecyclerView.ViewHolder {
         final ItemProductSupplierBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public PSViewHolder(@NonNull ItemProductSupplierBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for a Product-Supplier item.
+     */
     @NonNull
     @Override
     public PSViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -67,6 +92,9 @@ public class ProductSupplierAdapter extends RecyclerView.Adapter<ProductSupplier
         return new PSViewHolder(binding);
     }
 
+    /**
+     * Binds product-supplier data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull PSViewHolder holder, int position) {
         ProductSupplierDTO ps = list.get(position);

android/app/src/main/java/com/example/petstoremobile/adapters/PurchaseOrderAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying purchase orders in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -17,20 +24,32 @@ public class PurchaseOrderAdapter extends RecyclerView.Adapter<PurchaseOrderAdap
         void onPurchaseOrderClick(int position);
     }
 
+    /**
+     * Constructor for PurchaseOrderAdapter.
+     */
     public PurchaseOrderAdapter(List<PurchaseOrderDTO> list, OnPurchaseOrderClickListener listener) {
         this.list = list;
         this.listener = listener;
     }
 
+    /**
+     * ViewHolder for Purchase Order items.
+     */
     public static class POViewHolder extends RecyclerView.ViewHolder {
         final ItemPurchaseOrderBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public POViewHolder(@NonNull ItemPurchaseOrderBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for a Purchase Order item.
+     */
     @NonNull
     @Override
     public POViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -38,6 +57,9 @@ public class PurchaseOrderAdapter extends RecyclerView.Adapter<PurchaseOrderAdap
         return new POViewHolder(binding);
     }
 
+    /**
+     * Binds purchase order data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull POViewHolder holder, int position) {
         PurchaseOrderDTO po = list.get(position);

android/app/src/main/java/com/example/petstoremobile/adapters/SaleAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing sales in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -20,20 +27,32 @@ public class SaleAdapter extends RecyclerView.Adapter<SaleAdapter.SaleViewHolder
         void onSaleClick(int position);
     }
 
+    /**
+     * Constructor for SaleAdapter.
+     */
     public SaleAdapter(List<SaleDTO> saleList, OnSaleClickListener listener) {
         this.saleList = saleList;
         this.listener = listener;
     }
 
+    /**
+     * ViewHolder for Sale record items.
+     */
     public static class SaleViewHolder extends RecyclerView.ViewHolder {
         final ItemSaleBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public SaleViewHolder(@NonNull ItemSaleBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
+    /**
+     * Inflates the layout for a Sale record item.
+     */
     @NonNull
     @Override
     public SaleViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -41,6 +60,9 @@ public class SaleAdapter extends RecyclerView.Adapter<SaleAdapter.SaleViewHolder
         return new SaleViewHolder(binding);
     }
 
+    /**
+     * Binds sale transaction data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull SaleViewHolder holder, int position) {
         SaleDTO s = saleList.get(position);

android/app/src/main/java/com/example/petstoremobile/adapters/ServiceAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for displaying services in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -31,6 +38,9 @@ public class ServiceAdapter extends RecyclerView.Adapter<ServiceAdapter.ServiceV
         void onSelectionChanged(int count);
     }
 
+    /**
+     * Constructor for ServiceAdapter.
+     */
     public ServiceAdapter(List<ServiceDTO> serviceList, OnServiceClickListener clickListener) {
         this.serviceList = serviceList;
         this.clickListener = clickListener;
@@ -47,29 +57,40 @@ public class ServiceAdapter extends RecyclerView.Adapter<ServiceAdapter.ServiceV
         });
     }
 
+    /**
+     * Returns the list of selected keys for bulk deletion.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Clears all selected items and exits selection mode.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
     }
 
     /**
-     * ViewHolder class for service items.
+     * ViewHolder for Service items.
      */
     public static class ServiceViewHolder extends RecyclerView.ViewHolder {
         final ItemServiceBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public ServiceViewHolder(@NonNull ItemServiceBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
-    // Create a new row view
+    /**
+     * Inflates the layout for a Service item.
+     */
     @NonNull
     @Override
     public ServiceViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -77,7 +98,9 @@ public class ServiceAdapter extends RecyclerView.Adapter<ServiceAdapter.ServiceV
         return new ServiceViewHolder(binding);
     }
 
-    //populate the row with service data
+    /**
+     * Binds service data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull ServiceViewHolder holder, int position) {
         ServiceDTO service = serviceList.get(position);

android/app/src/main/java/com/example/petstoremobile/adapters/SupplierAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Adapter for showing suppliers in a list.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.view.LayoutInflater;
@@ -26,7 +33,9 @@ public class SupplierAdapter extends RecyclerView.Adapter<SupplierAdapter.Suppli
         void onSelectionChanged(int count);
     }
 
-    //Constructor
+    /**
+     * Constructor for SupplierAdapter.
+     */
     public SupplierAdapter(List<SupplierDTO> supplierList, OnSupplierClickListener supplierClickListener) {
         this.supplierList  = supplierList;
         this.supplierClickListener = supplierClickListener;
@@ -43,27 +52,40 @@ public class SupplierAdapter extends RecyclerView.Adapter<SupplierAdapter.Suppli
         });
     }
 
+    /**
+     * Returns the list of selected keys for bulk deletion.
+     */
     @Override
     public List<String> getSelectedKeys() {
         return selectionHelper.getSelectedKeys();
     }
 
+    /**
+     * Clears all selected items and exits selection mode.
+     */
     @Override
     public void clearSelection() {
         selectionHelper.clearSelection();
     }
 
-    // Get the controls of each row in recycler view
+    /**
+     * ViewHolder for Supplier items.
+     */
     public static class SupplierViewHolder extends RecyclerView.ViewHolder {
         final ItemSupplierBinding binding;
 
+        /**
+         * Initializes the ViewHolder with view binding.
+         */
         public SupplierViewHolder(@NonNull ItemSupplierBinding binding) {
             super(binding.getRoot());
             this.binding = binding;
         }
     }
 
-    // Create a new row view
+    /**
+     * Inflates the layout for a Supplier item.
+     */
     @NonNull
     @Override
     public SupplierViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
@@ -71,7 +93,9 @@ public class SupplierAdapter extends RecyclerView.Adapter<SupplierAdapter.Suppli
         return new SupplierViewHolder(binding);
     }
 
-    //populate the row with supplier data
+    /**
+     * Binds supplier data to the UI components.
+     */
     @Override
     public void onBindViewHolder(@NonNull SupplierViewHolder holder, int position) {
         SupplierDTO supplier = supplierList.get(position);

android/app/src/main/java/com/example/petstoremobile/adapters/WhiteTextArrayAdapter.java

@@ -1,3 +1,10 @@
+/*
+ * Custom array adapter that displays items with white text.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.adapters;
 
 import android.content.Context;
@@ -12,9 +19,8 @@ import androidx.core.content.ContextCompat;
 import com.example.petstoremobile.R;
 import java.util.List;
 
-/**
- * A class that overrides the arrayAdapter so the text color is white and background is transparent.
- */
+// A class that overrides the arrayAdapter so the text color changes based on theme
+// Used to make spinners have white text on dark background no matter the theme
 public class WhiteTextArrayAdapter<T> extends ArrayAdapter<T> {
     public WhiteTextArrayAdapter(@NonNull Context context, int resource, @NonNull T[] objects) {
         super(context, resource, objects);

android/app/src/main/java/com/example/petstoremobile/api/ActivityLogApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for activity log endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.ActivityLogDTO;
@@ -8,8 +15,10 @@ import retrofit2.Call;
 import retrofit2.http.GET;
 import retrofit2.http.Query;
 
+// api calls to get activity logs
 public interface ActivityLogApi {
 
+    // Get activity logs with filters
     @GET("api/v1/activity-logs")
     Call<List<ActivityLogDTO>> getActivityLogs(
             @Query("limit") int limit,

android/app/src/main/java/com/example/petstoremobile/api/AdoptionApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for adoption endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.AdoptionDTO;
@@ -14,8 +21,10 @@ import retrofit2.http.PUT;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for adoptions
 public interface AdoptionApi {
 
+    // Get all adoptions with filters
     @GET("api/v1/adoptions")
     Call<PageResponse<AdoptionDTO>> getAllAdoptions(
             @Query("page") int page,
@@ -27,18 +36,23 @@ public interface AdoptionApi {
             @Query("employeeId") Long employeeId,
             @Query("sort") String sort);
 
+    // Get adoption by id
     @GET("api/v1/adoptions/{id}")
     Call<AdoptionDTO> getAdoptionById(@Path("id") Long id);
 
+    // Create adoption
     @POST("api/v1/adoptions")
     Call<AdoptionDTO> createAdoption(@Body AdoptionDTO adoption);
 
+    // Update adoption
     @PUT("api/v1/adoptions/{id}")
     Call<AdoptionDTO> updateAdoption(@Path("id") Long id, @Body AdoptionDTO adoption);
 
+    // Delete adoption
     @DELETE("api/v1/adoptions/{id}")
     Call<Void> deleteAdoption(@Path("id") Long id);
 
+    // Bulk delete adoptions
     @HTTP(method = "DELETE", path = "api/v1/adoptions", hasBody = true)
     Call<Void> bulkDeleteAdoptions(@Body BulkDeleteRequest request);
 }

android/app/src/main/java/com/example/petstoremobile/api/AppointmentApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for appointment endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.AppointmentDTO;
@@ -14,8 +21,10 @@ import retrofit2.http.PUT;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for appointments
 public interface AppointmentApi {
 
+    // Get all appointments with filters
     @GET("api/v1/appointments")
     Call<PageResponse<AppointmentDTO>> getAllAppointments(
             @Query("page") int page,
@@ -27,18 +36,23 @@ public interface AppointmentApi {
             @Query("employeeId") Long employeeId,
             @Query("sort") String sort);
 
+    // Get appointment by id
     @GET("api/v1/appointments/{id}")
     Call<AppointmentDTO> getAppointmentById(@Path("id") Long id);
 
+    // Create appointment
     @POST("api/v1/appointments")
     Call<AppointmentDTO> createAppointment(@Body AppointmentDTO appointment);
 
+    // Update appointment
     @PUT("api/v1/appointments/{id}")
     Call<AppointmentDTO> updateAppointment(@Path("id") Long id, @Body AppointmentDTO appointment);
 
+    // Delete appointment
     @DELETE("api/v1/appointments/{id}")
     Call<Void> deleteAppointment(@Path("id") Long id);
 
+    // Bulk delete appointments
     @HTTP(method = "DELETE", path = "api/v1/appointments", hasBody = true)
     Call<Void> bulkDeleteAppointments(@Body BulkDeleteRequest request);
 }

android/app/src/main/java/com/example/petstoremobile/api/CategoryApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for category endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.CategoryDTO;
@@ -6,8 +13,10 @@ import retrofit2.Call;
 import retrofit2.http.GET;
 import retrofit2.http.Query;
 
+// api calls for categories
 public interface CategoryApi {
 
+    // Get all categories with pagination
     @GET("api/v1/categories")
     Call<PageResponse<CategoryDTO>> getAllCategories(
             @Query("page") int page,

android/app/src/main/java/com/example/petstoremobile/api/ChatApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for chat and conversation endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.ConversationDTO;
@@ -12,15 +19,18 @@ import retrofit2.http.GET;
 import retrofit2.http.PUT;
 import retrofit2.http.Path;
 
-//api calls to get conversations
+// api calls for chat conversations
 public interface ChatApi {
     
+    // Get all conversations
     @GET("api/v1/chat/conversations")
     Call<List<ConversationDTO>> getAllConversations();
 
+    // Get conversation by id
     @GET("api/v1/chat/conversations/{conversationId}")
     Call<ConversationDTO> getConversationById(@Path("conversationId") Long conversationId);
 
+    // Update conversation status
     @PUT("api/v1/chat/conversations/{conversationId}")
     Call<ConversationDTO> updateConversationStatus(@Path("conversationId") Long conversationId, @Body UpdateConversationStatusRequest request);
 

android/app/src/main/java/com/example/petstoremobile/api/CouponApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for coupon endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.CouponDTO;
@@ -6,9 +13,12 @@ import com.example.petstoremobile.dtos.PageResponse;
 import java.util.List;
 
 import retrofit2.Call;
+import com.example.petstoremobile.dtos.BulkDeleteRequest;
+
 import retrofit2.http.Body;
 import retrofit2.http.DELETE;
 import retrofit2.http.GET;
+import retrofit2.http.HTTP;
 import retrofit2.http.POST;
 import retrofit2.http.PUT;
 import retrofit2.http.Path;
@@ -39,6 +49,6 @@ public interface CouponApi {
     @DELETE("api/v1/coupons/{id}")
     Call<Void> deleteCoupon(@Path("id") Long id);
 
-    @DELETE("api/v1/coupons")
-    Call<Void> bulkDeleteCoupons(@Query("ids") List<Long> ids);
+    @HTTP(method = "DELETE", path = "api/v1/coupons", hasBody = true)
+    Call<Void> bulkDeleteCoupons(@Body BulkDeleteRequest request);
 }

android/app/src/main/java/com/example/petstoremobile/api/CustomerApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for customer endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.CustomerDTO;
@@ -15,23 +22,30 @@ import retrofit2.http.PUT;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for customers
 public interface CustomerApi {
 
+    // Get all customers with pagination
     @GET("api/v1/customers")
     Call<PageResponse<CustomerDTO>> getAllCustomers(@Query("page") int page, @Query("size") int size);
 
+    // Get customer by id
     @GET("api/v1/customers/{customerId}")
     Call<CustomerDTO> getCustomerById(@Path("customerId") Long customerId);
 
+    // Update customer
     @PUT("api/v1/customers/{customerId}")
     Call<CustomerDTO> updateCustomer(@Path("customerId") Long customerId, @Body CustomerDTO customer);
 
+    // Delete customer
     @DELETE("api/v1/customers/{customerId}")
     Call<Void> deleteCustomer(@Path("customerId") Long customerId);
 
+    // Register customer
     @POST("api/v1/auth/register")
     Call<CustomerDTO> registerCustomer(@Body CustomerDTO customer);
 
+    // Get customer dropdowns
     @GET("api/v1/dropdowns/customers")
     Call<List<DropdownDTO>> getCustomerDropdowns();
 }

android/app/src/main/java/com/example/petstoremobile/api/EmployeeApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for employee endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.EmployeeDTO;
@@ -5,28 +12,28 @@ import com.example.petstoremobile.dtos.PageResponse;
 import retrofit2.Call;
 import retrofit2.http.*;
 
+// api calls for employees
 public interface EmployeeApi {
 
+    // Get all employees with pagination
     @GET("api/v1/employees")
     Call<PageResponse<EmployeeDTO>> getAllEmployees(
             @Query("page") int page,
             @Query("size") int size);
 
+    // Get employee by id
     @GET("api/v1/employees/{id}")
     Call<EmployeeDTO> getEmployeeById(@Path("id") Long id);
 
+    // Create employee
     @POST("api/v1/employees")
     Call<EmployeeDTO> createEmployee(@Body EmployeeDTO employee);
 
+    // Update employee
     @PUT("api/v1/employees/{id}")
     Call<EmployeeDTO> updateEmployee(@Path("id") Long id, @Body EmployeeDTO employee);
 
+    // Delete employee
     @DELETE("api/v1/employees/{id}")
     Call<Void> deleteEmployee(@Path("id") Long id);
 }
-
-
-
-
-
-

android/app/src/main/java/com/example/petstoremobile/api/InventoryApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for inventory endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.BulkDeleteRequest;
@@ -14,8 +21,10 @@ import retrofit2.http.PUT;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for inventory
 public interface InventoryApi {
 
+    // Get all inventory with filters
     @GET("api/v1/inventory")
     Call<PageResponse<InventoryDTO>> getAllInventory(
             @Query("page") int page,
@@ -24,23 +33,23 @@ public interface InventoryApi {
             @Query("storeId") Long storeId,
             @Query("sort") String sort);
 
-    // GET /api/v1/inventory/{id}
+    // Get inventory by id
     @GET("api/v1/inventory/{id}")
     Call<InventoryDTO> getInventoryById(@Path("id") Long id);
 
-    // POST /api/v1/inventory
+    // Create inventory
     @POST("api/v1/inventory")
     Call<InventoryDTO> createInventory(@Body InventoryDTO request);
 
-    // PUT /api/v1/inventory/{id}
+    // Update inventory
     @PUT("api/v1/inventory/{id}")
     Call<InventoryDTO> updateInventory(@Path("id") Long id, @Body InventoryDTO request);
 
-    // DELETE /api/v1/inventory/{id}
+    // Delete inventory
     @DELETE("api/v1/inventory/{id}")
     Call<Void> deleteInventory(@Path("id") Long id);
 
-    // DELETE /api/v1/inventory (bulk delete)
+    // Bulk delete inventory
     @HTTP(method = "DELETE", path = "api/v1/inventory", hasBody = true)
     Call<Void> bulkDeleteInventory(@Body BulkDeleteRequest request);
 }

android/app/src/main/java/com/example/petstoremobile/api/MessageApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for message endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.MessageDTO;
@@ -15,15 +22,18 @@ import retrofit2.http.Part;
 import retrofit2.http.Path;
 import retrofit2.http.Streaming;
 
-//api calls to get and send messages
+// api calls for messages
 public interface MessageApi {
 
+    // Get messages for a conversation
     @GET("api/v1/chat/conversations/{id}/messages")
     Call<List<MessageDTO>> getMessages(@Path("id") Long conversationId);
 
+    // Send a message
     @POST("api/v1/chat/conversations/{id}/messages")
     Call<MessageDTO> sendMessage(@Path("id") Long conversationId, @Body SendMessageRequest request);
 
+    // Send a message with attachment
     @Multipart
     @POST("api/v1/chat/conversations/{id}/attachments")
     Call<MessageDTO> sendMessageWithAttachment(
@@ -32,6 +42,7 @@ public interface MessageApi {
             @Part MultipartBody.Part file
     );
 
+    // Download attachment
     @GET("api/v1/chat/messages/{id}/attachment")
     @Streaming
     Call<ResponseBody> downloadAttachment(@Path("id") Long messageId);

android/app/src/main/java/com/example/petstoremobile/api/PetApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for pet endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.BulkDeleteRequest;
@@ -38,18 +45,23 @@ public interface PetApi {
             @Query("sort") String sort
     );
 
+    // Get pets by customer id
     @GET("api/v1/dropdowns/customers/{customerId}/pets")
     Call<List<DropdownDTO>> getCustomerPets(@Path("customerId") Long customerId);
 
+    // Get adoption pets
     @GET("api/v1/dropdowns/adoption-pets")
     Call<List<DropdownDTO>> getAdoptionPets(@Query("storeId") Long storeId);
 
+    // Get pet dropdowns
     @GET("api/v1/dropdowns/pets")
     Call<List<DropdownDTO>> getPetDropdowns();
 
+    // Get pet species dropdowns
     @GET("api/v1/dropdowns/pet-species")
     Call<List<DropdownDTO>> getPetSpeciesDropdowns();
 
+    // Get pet breeds dropdowns
     @GET("api/v1/dropdowns/pet-breeds")
     Call<List<DropdownDTO>> getPetBreedsDropdowns(@Query("species") String species);
 
@@ -81,5 +93,4 @@ public interface PetApi {
     // Delete pet image
     @DELETE("api/v1/pets/{id}/image")
     Call<Void> deletePetImage(@Path("id") Long id);
-
 }

android/app/src/main/java/com/example/petstoremobile/api/ProductApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for product endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.DropdownDTO;
@@ -9,9 +16,12 @@ import retrofit2.http.*;
 
 import java.util.List;
 
+// api calls for products
 public interface ProductApi {
+    // endpoint for downloading the product's image file
     String PRODUCT_IMAGE_PATH = "api/v1/products/%d/image";
 
+    // Get all products with filters
     @GET("api/v1/products")
     Call<PageResponse<ProductDTO>> getAllProducts(
             @Query("q") String query,
@@ -20,28 +30,36 @@ public interface ProductApi {
             @Query("size") int size,
             @Query("sort") String sort);
 
+    // Get product by id
     @GET("api/v1/products/{id}")
     Call<ProductDTO> getProductById(@Path("id") Long id);
 
+    // Create product
     @POST("api/v1/products")
     Call<ProductDTO> createProduct(@Body ProductDTO product);
 
+    // Update product
     @PUT("api/v1/products/{id}")
     Call<ProductDTO> updateProduct(@Path("id") Long id, @Body ProductDTO product);
 
+    // Delete product
     @DELETE("api/v1/products/{id}")
     Call<Void> deleteProduct(@Path("id") Long id);
 
+    // Upload product image
     @Multipart
     @POST("api/v1/products/{id}/image")
     Call<Void> uploadProductImage(@Path("id") Long id, @Part MultipartBody.Part image);
 
+    // Delete product image
     @DELETE("api/v1/products/{id}/image")
     Call<Void> deleteProductImage(@Path("id") Long id);
 
+    // Get product dropdowns
     @GET("api/v1/dropdowns/products")
     Call<List<DropdownDTO>> getProductDropdowns();
 
+    // Get category dropdowns
     @GET("api/v1/dropdowns/categories")
     Call<List<DropdownDTO>> getCategoryDropdowns();
 }

android/app/src/main/java/com/example/petstoremobile/api/ProductSupplierApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for product-supplier endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.BulkDeleteRequest;
@@ -6,8 +13,10 @@ import com.example.petstoremobile.dtos.ProductSupplierDTO;
 import retrofit2.Call;
 import retrofit2.http.*;
 
+// api calls for product-supplier relationships
 public interface ProductSupplierApi {
 
+    // Get all product-suppliers with filters
     @GET("api/v1/product-suppliers")
     Call<PageResponse<ProductSupplierDTO>> getAllProductSuppliers(
             @Query("page") int page,
@@ -17,24 +26,30 @@ public interface ProductSupplierApi {
             @Query("supplierId") Long supplierId,
             @Query("sort") String sort);
 
+    // Get product-supplier by composite id
     @GET("api/v1/product-suppliers/{productId}/{supplierId}")
     Call<ProductSupplierDTO> getProductSupplierById(
             @Path("productId") Long productId,
             @Path("supplierId") Long supplierId);
 
+    // Create product-supplier
     @POST("api/v1/product-suppliers")
     Call<ProductSupplierDTO> createProductSupplier(@Body ProductSupplierDTO dto);
 
+    // Update product-supplier
     @PUT("api/v1/product-suppliers/{productId}/{supplierId}")
     Call<ProductSupplierDTO> updateProductSupplier(
             @Path("productId") Long productId,
             @Path("supplierId") Long supplierId,
             @Body ProductSupplierDTO dto);
 
+    // Delete product-supplier
     @DELETE("api/v1/product-suppliers/{productId}/{supplierId}")
     Call<Void> deleteProductSupplier(
             @Path("productId") Long productId,
             @Path("supplierId") Long supplierId);
+
+    // Bulk delete product-suppliers
     @HTTP(method = "DELETE", path = "api/v1/product-suppliers", hasBody = true)
     Call<Void> bulkDeleteProductSuppliers(@Body BulkDeleteRequest request);
 }

android/app/src/main/java/com/example/petstoremobile/api/PurchaseOrderApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for purchase order endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.PageResponse;
@@ -7,8 +14,10 @@ import retrofit2.http.GET;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for purchase orders
 public interface PurchaseOrderApi {
 
+    // Get all purchase orders with filters
     @GET("api/v1/purchase-orders")
     Call<PageResponse<PurchaseOrderDTO>> getAllPurchaseOrders(
             @Query("page") int page,
@@ -17,6 +26,7 @@ public interface PurchaseOrderApi {
             @Query("storeId") Long storeId,
             @Query("sort") String sort);
 
+    // Get purchase order by id
     @GET("api/v1/purchase-orders/{id}")
     Call<PurchaseOrderDTO> getPurchaseOrderById(@Path("id") Long id);
 }

android/app/src/main/java/com/example/petstoremobile/api/RefundApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for refund endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.RefundDTO;
@@ -6,20 +13,26 @@ import retrofit2.http.*;
 
 import java.util.List;
 
+// api calls for refunds
 public interface RefundApi {
 
+    // Get all refunds
     @GET("api/v1/refunds")
     Call<List<RefundDTO>> getAllRefunds();
 
+    // Get refund by id
     @GET("api/v1/refunds/{id}")
     Call<RefundDTO> getRefundById(@Path("id") Long id);
 
+    // Create refund
     @POST("api/v1/refunds")
     Call<RefundDTO> createRefund(@Body RefundDTO refund);
 
+    // Update refund
     @PUT("api/v1/refunds/{id}")
     Call<RefundDTO> updateRefund(@Path("id") Long id, @Body RefundDTO refund);
 
+    // Delete refund
     @DELETE("api/v1/refunds/{id}")
     Call<Void> deleteRefund(@Path("id") Long id);
 }

android/app/src/main/java/com/example/petstoremobile/api/SaleApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for sale endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.PageResponse;
@@ -10,8 +17,10 @@ import retrofit2.http.POST;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for sales
 public interface SaleApi {
 
+    // Get all sales with filters
     @GET("api/v1/sales")
     Call<PageResponse<SaleDTO>> getAllSales(
             @Query("page") int page,
@@ -23,9 +32,11 @@ public interface SaleApi {
             @Query("customerId") Long customerId,
             @Query("sort") String sort);
 
+    // Get sale by id
     @GET("api/v1/sales/{id}")
     Call<SaleDTO> getSaleById(@Path("id") Long id);
 
+    // Create sale
     @POST("api/v1/sales")
     Call<SaleDTO> createSale(@Body SaleDTO sale);
 }

android/app/src/main/java/com/example/petstoremobile/api/ServiceApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for service endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.BulkDeleteRequest;

android/app/src/main/java/com/example/petstoremobile/api/StoreApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for store endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.DropdownDTO;
@@ -11,16 +18,20 @@ import retrofit2.http.GET;
 import retrofit2.http.Path;
 import retrofit2.http.Query;
 
+// api calls for stores
 public interface StoreApi {
 
+    // Get all stores with pagination
     @GET("api/v1/stores")
     Call<PageResponse<StoreDTO>> getAllStores(
             @Query("page") int page,
             @Query("size") int size);
 
+    // Get store dropdowns
     @GET("api/v1/dropdowns/stores")
     Call<List<DropdownDTO>> getStoreDropdowns();
 
+    // Get employees of a specific store
     @GET("api/v1/dropdowns/stores/{storeId}/employees")
     Call<List<DropdownDTO>> getStoreEmployees(@Path("storeId") Long storeId);
 }

android/app/src/main/java/com/example/petstoremobile/api/SupplierApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for supplier endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.BulkDeleteRequest;

android/app/src/main/java/com/example/petstoremobile/api/UserApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for user endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api;
 
 import com.example.petstoremobile.dtos.PageResponse;
@@ -7,9 +14,12 @@ import retrofit2.Call;
 import retrofit2.http.GET;
 import retrofit2.http.Query;
 
+// api calls for users
 public interface UserApi {
+    // endpoint for downloading the user's avatar file
     String AVATAR_PATH = "api/v1/users/%d/avatar/file";
 
+    // Get all users with filters
     @GET("api/v1/users")
     Call<PageResponse<UserDTO>> getUsers(@Query("role") String role, @Query("page") int page, @Query("size") int size);
 }

android/app/src/main/java/com/example/petstoremobile/api/auth/AuthApi.java

@@ -1,3 +1,10 @@
+/*
+ * Retrofit interface for login and registration endpoints.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api.auth;
 
 import com.example.petstoremobile.dtos.AuthDTO;

android/app/src/main/java/com/example/petstoremobile/api/auth/AuthInterceptor.java

@@ -1,3 +1,10 @@
+/*
+ * Interceptor that attaches the auth token to outgoing requests.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api.auth;
 
 import androidx.annotation.NonNull;
@@ -23,19 +30,26 @@ public class AuthInterceptor implements Interceptor {
         String token = tokenManager.getToken();
         String url = chain.request().url().toString();
 
-        if (url.contains("auth/login") || url.contains("auth/register")) {
+        boolean isAuthEndpoint = url.contains("auth/login") || url.contains("auth/register");
+
+        if (isAuthEndpoint) {
             return chain.proceed(chain.request());
         }
 
-        //If we have a token then add it to the request
+        Response response;
         if (token != null) {
             Request request = chain.request().newBuilder()
                     .addHeader("Authorization", "Bearer " + token)
                     .build();
-            return chain.proceed(request);
+            response = chain.proceed(request);
+        } else {
+            response = chain.proceed(chain.request());
         }
 
-        //If no token then just pass the request
-        return chain.proceed(chain.request());
+        if (response.code() == 401) {
+            tokenManager.forceLogout();
+        }
+
+        return response;
     }
 }

android/app/src/main/java/com/example/petstoremobile/api/auth/TokenManager.java

@@ -1,6 +1,14 @@
+/*
+ * Handles saving and retrieving the authentication token.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.api.auth;
 
 import android.content.Context;
+import android.content.Intent;
 import android.content.SharedPreferences;
 
 import javax.inject.Inject;
@@ -8,8 +16,11 @@ import javax.inject.Singleton;
 
 import dagger.hilt.android.qualifiers.ApplicationContext;
 
+//Used to save and retrieve login data
 @Singleton
 public class TokenManager {
+    public static final String ACTION_FORCE_LOGOUT = "com.example.petstoremobile.ACTION_FORCE_LOGOUT";
+
     private static final String TOKEN_KEY = "token";
     private static final String USERNAME_KEY = "username";
     private static final String ROLE_KEY = "role";
@@ -17,13 +28,22 @@ public class TokenManager {
     private static final String USER_ID_KEY = "user_id";
     private static final String PRIMARY_STORE_ID_KEY = "primary_store_id";
 
+    private final Context context;
     private SharedPreferences prefs;
 
     @Inject
     public TokenManager(@ApplicationContext Context context) {
+        this.context = context;
         prefs = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);
     }
 
+    public void forceLogout() {
+        clearLoginData();
+        Intent intent = new Intent(ACTION_FORCE_LOGOUT);
+        intent.setPackage(context.getPackageName());
+        context.sendBroadcast(intent);
+    }
+
     //save login data after login
     public void saveLoginData(String token, String username, String role) {
         prefs.edit()

android/app/src/main/java/com/example/petstoremobile/di/NetworkModule.java

@@ -1,3 +1,10 @@
+/*
+ * Sets up the Retrofit client and dependency injection for network calls.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.di;
 
 import android.content.Context;

android/app/src/main/java/com/example/petstoremobile/dtos/ActivityLogDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for activity log entries.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for activity logs.
+ */
 public class ActivityLogDTO {
     private Long logId;
     private String activity;

android/app/src/main/java/com/example/petstoremobile/dtos/AdoptionDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for adoption records.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.math.BigDecimal;
 
+/**
+ * Data Transfer Object for pet adoptions.
+ */
 public class AdoptionDTO {
 
     private Long adoptionId;

android/app/src/main/java/com/example/petstoremobile/dtos/AppointmentDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for appointments.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for appointments.
+ */
 public class AppointmentDTO {
 
     private Long appointmentId;

android/app/src/main/java/com/example/petstoremobile/dtos/AuthDTO.java

@@ -1,6 +1,15 @@
+/*
+ * Data transfer object for authentication requests and responses.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
-//Used to send login data to the backend
+/**
+ * Data Transfer Object for authentication credentials.
+ */
 public class AuthDTO {
     public static class LoginRequest {
         private String username;

android/app/src/main/java/com/example/petstoremobile/dtos/AvatarUploadResponse.java

@@ -1,5 +1,15 @@
+/*
+ * Response object returned after uploading an avatar image.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Response containing the URL of a newly uploaded avatar.
+ */
 public class AvatarUploadResponse {
     private String avatarUrl;
     private String message;

android/app/src/main/java/com/example/petstoremobile/dtos/BulkDeleteRequest.java

@@ -1,22 +1,32 @@
+/*
+ * Request object for deleting multiple items at once.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.util.List;
 
+/**
+ * Request body for deleting multiple records at once.
+ */
 public class BulkDeleteRequest {
-    private List<String> ids;
+    private List<Long> ids;
 
     public BulkDeleteRequest() {
     }
 
-    public BulkDeleteRequest(List<String> ids) {
+    public BulkDeleteRequest(List<Long> ids) {
         this.ids = ids;
     }
 
-    public List<String> getIds() {
+    public List<Long> getIds() {
         return ids;
     }
 
-    public void setIds(List<String> ids) {
+    public void setIds(List<Long> ids) {
         this.ids = ids;
     }
 }

android/app/src/main/java/com/example/petstoremobile/dtos/CategoryDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for categories.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for product categories.
+ */
 public class CategoryDTO {
     private Long categoryId;
     private String categoryName;

android/app/src/main/java/com/example/petstoremobile/dtos/ConversationDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for chat conversations.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for chat conversations.
+ */
 public class ConversationDTO {
     private Long id;
     private Long customerId;

android/app/src/main/java/com/example/petstoremobile/dtos/CouponDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for coupons.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.math.BigDecimal;
 
+/**
+ * Data Transfer Object for coupons.
+ */
 public class CouponDTO {
     private Long couponId;
     private String couponCode;

android/app/src/main/java/com/example/petstoremobile/dtos/CustomerDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for customers.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import com.google.gson.annotations.SerializedName;
 
+/**
+ * Data Transfer Object for customers.
+ */
 public class CustomerDTO {
     @SerializedName("id")
     private Long customerId;

android/app/src/main/java/com/example/petstoremobile/dtos/DropdownDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object used to populate dropdown menus.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for simple dropdown selection lists.
+ */
 public class DropdownDTO {
     private Long id;
     private String label;

android/app/src/main/java/com/example/petstoremobile/dtos/EmployeeDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for employees.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for employees.
+ */
 public class EmployeeDTO {
 
     private Long id;

android/app/src/main/java/com/example/petstoremobile/dtos/ErrorResponse.java

@@ -1,7 +1,15 @@
+/*
+ * Represents an error response from the server.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
-//Used to get messages of any errors from the backend
-
+/**
+ * Used to get messages of any errors from the backend.
+ */
 public class ErrorResponse {
     private String message;
 

android/app/src/main/java/com/example/petstoremobile/dtos/InventoryDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for inventory items.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for inventory stock.
+ */
 public class InventoryDTO {
     // Response fields (from backend InventoryResponse)
     private Long inventoryId;

android/app/src/main/java/com/example/petstoremobile/dtos/MessageDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for chat messages.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import com.google.gson.annotations.SerializedName;
 
+/**
+ * Data Transfer Object for chat messages.
+ */
 public class MessageDTO {
 
     @SerializedName("id")

android/app/src/main/java/com/example/petstoremobile/dtos/PageResponse.java

@@ -1,8 +1,17 @@
+/*
+ * Wrapper for paginated responses from the server.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.util.List;
 
-//Used to get data from the API
+/**
+ * Generic response wrapper for paginated API results.
+ */
 public class PageResponse<T> {
     private List<T> content;
     private int totalPages;

android/app/src/main/java/com/example/petstoremobile/dtos/PetDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for pets.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object representing a pet.
+ */
 public class PetDTO {
     private Long petId;
     private String petName;

android/app/src/main/java/com/example/petstoremobile/dtos/ProductDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for products.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.math.BigDecimal;
 
+/**
+ * Data Transfer Object for products.
+ */
 public class ProductDTO {
     private Long prodId;
     private String prodName;

android/app/src/main/java/com/example/petstoremobile/dtos/ProductSupplierDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for product-supplier relationships.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.math.BigDecimal;
 
+/**
+ * Data Transfer Object for mapping products to suppliers.
+ */
 public class ProductSupplierDTO {
     private Long productId;
     private String productName;

android/app/src/main/java/com/example/petstoremobile/dtos/PurchaseOrderDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for purchase orders.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for purchase orders.
+ */
 public class PurchaseOrderDTO {
     private Long purchaseOrderId;
     private Long supId;

android/app/src/main/java/com/example/petstoremobile/dtos/RefundDTO.java

@@ -1,7 +1,17 @@
+/*
+ * Data transfer object for refunds.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.math.BigDecimal;
 
+/**
+ * Data Transfer Object for refund processing.
+ */
 public class RefundDTO {
     // Response fields
     private Long id;

android/app/src/main/java/com/example/petstoremobile/dtos/SaleDTO.java

@@ -1,8 +1,18 @@
+/*
+ * Data transfer object for sales.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
 import java.math.BigDecimal;
 import java.util.List;
 
+/**
+ * Data Transfer Object for sales transactions.
+ */
 public class SaleDTO {
     // Response fields
     private Long saleId;

android/app/src/main/java/com/example/petstoremobile/dtos/SendMessageRequest.java

@@ -1,5 +1,15 @@
+/*
+ * Request object for sending a new chat message.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Request body for sending a new chat message.
+ */
 public class SendMessageRequest {
 
     private String content;

android/app/src/main/java/com/example/petstoremobile/dtos/ServiceDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for services.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for services.
+ */
 public class ServiceDTO {
     private Long serviceId;
     private String serviceName;

android/app/src/main/java/com/example/petstoremobile/dtos/StoreDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for store information.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for store information.
+ */
 public class StoreDTO {
     private Long storeId;
     private String storeName;

android/app/src/main/java/com/example/petstoremobile/dtos/SupplierDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for suppliers.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for suppliers.
+ */
 public class SupplierDTO {
     private Long supId;
     private String supCompany;

android/app/src/main/java/com/example/petstoremobile/dtos/UpdateConversationStatusRequest.java

@@ -1,5 +1,15 @@
+/*
+ * Request object for changing a conversation's status.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Request body for updating chat conversation status.
+ */
 public class UpdateConversationStatusRequest {
     private String status;
 

android/app/src/main/java/com/example/petstoremobile/dtos/UserDTO.java

@@ -1,5 +1,15 @@
+/*
+ * Data transfer object for user account information.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.dtos;
 
+/**
+ * Data Transfer Object for user account details.
+ */
 public class UserDTO {
     private Long id;
     private String username;

android/app/src/main/java/com/example/petstoremobile/fragments/ChatFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for the real-time chat screen.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments;
 
 import android.app.Activity;
@@ -65,6 +72,9 @@ import okhttp3.MultipartBody;
 import okhttp3.RequestBody;
 import okhttp3.ResponseBody;
 
+/**
+ * Fragment for handling customer support chat.
+ */
 @AndroidEntryPoint
 public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickListener, StompChatManager.MessageListener,
         StompChatManager.ConversationListener, StompChatManager.ConnectionListener {
@@ -90,6 +100,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
     private StompChatManager stompChatManager;
     private ActivityResultLauncher<Intent> attachmentLauncher;
 
+    /**
+     * Initializes the view model and attachment launcher.
+     */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -105,6 +118,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         );
     }
 
+    /**
+     * Inflates the layout and sets up UI event listeners.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater,
                              ViewGroup container, Bundle savedInstanceState) {
@@ -137,6 +153,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         return binding.getRoot();
     }
 
+    /**
+     * Sets up the logic to open and close the chat drawer.
+     */
     private void setupDrawerToggles() {
         binding.headerActiveChats.setOnClickListener(v -> {
             if (binding.rvActiveChats.getVisibility() == View.VISIBLE) {
@@ -159,6 +178,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Configures the adapters and layout managers for chat lists and message history.
+     */
     private void setupRecyclerViews() {
         activeChatAdapter = new ChatAdapter(activeChatList, this);
         binding.rvActiveChats.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -187,6 +209,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         setConversationActive(false, null);
     }
 
+    /**
+     * Displays a full-screen image preview for message attachments.
+     */
     private void showFullScreenImage(Message message) {
         if (baseUrl == null || message.getId() == null) return;
 
@@ -208,6 +233,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         dialog.show();
     }
 
+    /**
+     * Initiates the download process for a message attachment.
+     */
     private void downloadFile(Message message) {
         if (message.getId() == null) return;
 
@@ -227,6 +255,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Saves the downloaded file body to the device's downloads folder.
+     */
     private void saveFileToDownloads(ResponseBody body, String fileName, String mimeType) {
         android.os.Handler mainHandler = new android.os.Handler(android.os.Looper.getMainLooper());
         new Thread(() -> {
@@ -270,6 +301,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         }).start();
     }
 
+    /**
+     * Observes LiveData from the ViewModel to update chat lists and messages.
+     */
     private void observeViewModel() {
         viewModel.getActiveChats().observe(getViewLifecycleOwner(), list -> {
             activeChatList.clear();
@@ -300,12 +334,18 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         viewModel.getIsLoading().observe(getViewLifecycleOwner(), this::setLoading);
     }
 
+    /**
+     * Toggles the visibility of the progress bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null && binding.progressBar != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Updates the chat header and input state if the active conversation changes.
+     */
     private void updateTitleAndStateIfActive(List<Chat> list) {
         if (activeConversationId != null) {
             for (Chat chat : list) {
@@ -318,6 +358,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         }
     }
 
+    /**
+     * Loads initial chat data and establishes WebSocket connection.
+     */
     private void loadInitialData() {
         String token = tokenManager.getToken();
         Long currentUserId = tokenManager.getUserId();
@@ -353,6 +396,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         }
     }
 
+    /**
+     * Handles clicks on a chat from the drawer to switch the active conversation.
+     */
     @Override
     public void onChatClick(Chat chat) {
         activeConversationId = Long.parseLong(chat.getChatId());
@@ -368,6 +414,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         viewModel.loadMessageHistory(activeConversationId);
     }
 
+    /**
+     * Closes the active chat conversation.
+     */
     private void closeChat() {
         if (activeConversationId == null) return;
 
@@ -392,6 +441,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Sends a text message to the active conversation.
+     */
     private void sendMessage() {
         if (activeConversationId == null) return;
         String text = binding.etMessage.getText().toString().trim();
@@ -408,12 +460,18 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Opens a file picker to select an attachment.
+     */
     private void selectAttachment() {
         Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
         intent.setType("*/*");
         attachmentLauncher.launch(intent);
     }
 
+    /**
+     * Displays a preview of the selected attachment.
+     */
     private void showAttachmentPreview(Uri uri) {
         pendingAttachmentUri = uri;
         binding.layoutAttachmentPreview.setVisibility(View.VISIBLE);
@@ -427,11 +485,17 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         }
     }
 
+    /**
+     * Removes the currently selected attachment from the preview.
+     */
     private void removeAttachment() {
         pendingAttachmentUri = null;
         binding.layoutAttachmentPreview.setVisibility(View.GONE);
     }
 
+    /**
+     * Sends a message with a file attachment.
+     */
     private void sendWithAttachment(Uri uri) {
         if (activeConversationId == null) return;
 
@@ -468,6 +532,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Callback for when a new message is received through the WebSocket.
+     */
     @Override
     public void onMessageReceived(MessageDTO dto) {
         requireActivity().runOnUiThread(() -> {
@@ -478,6 +545,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Callback for when a conversation's status or last message is updated.
+     */
     @Override
     public void onConversationUpdated(ConversationDTO dto) {
         requireActivity().runOnUiThread(() -> {
@@ -489,6 +559,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Callback for when the WebSocket connection is successfully opened.
+     */
     @Override
     public void onSocketOpened() {
         if (!isAdded()) return;
@@ -498,12 +571,18 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Callback for when the WebSocket connection is closed.
+     */
     @Override
     public void onSocketClosed() {
         if (!isAdded()) return;
         requireActivity().runOnUiThread(viewModel::loadConversations);
     }
 
+    /**
+     * Callback for when a WebSocket error occurs.
+     */
     @Override
     public void onSocketError() {
         if (!isAdded()) return;
@@ -513,6 +592,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         });
     }
 
+    /**
+     * Scrolls the message list to the most recent message.
+     */
     private void scrollToBottom() {
         if (!messageList.isEmpty()) {
             binding.rvMessages.post(() ->
@@ -520,6 +602,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         }
     }
 
+    /**
+     * Updates the UI state based on whether a conversation is active and its status.
+     */
     private void setConversationActive(boolean active, String status) {
         boolean isClosed = "CLOSED".equalsIgnoreCase(status);
         UIUtils.setViewsEnabled(active && !isClosed, binding.btnSend, binding.etMessage, binding.btnAttach);
@@ -541,6 +626,9 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         }
     }
 
+    /**
+     * Cleans up resources and disconnects the WebSocket when the view is destroyed.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/ListFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Base fragment that provides common list and search functionality.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments;
 
 import android.os.Bundle;
@@ -23,7 +30,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
-//The Fragment for the displaying the list of entities to be viewed
+/**
+ * Fragment that serves as a container for various list-based screens, providing a navigation drawer.
+ */
 @AndroidEntryPoint
 public class ListFragment extends Fragment {
 
@@ -97,6 +106,9 @@ public class ListFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Cleans up the binding when the view is destroyed.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/ProfileFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for viewing and editing the user's profile.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments;
 
 import android.net.Uri;
@@ -173,12 +180,18 @@ public class ProfileFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Toggles the visibility of the progress bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null && binding.progressBar != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Cleans up the binding when the view is destroyed.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/ActivityLogFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing the activity log.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.app.DatePickerDialog;
@@ -34,6 +41,9 @@ import java.util.List;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for viewing application activity logs with various filtering options.
+ */
 @AndroidEntryPoint
 public class ActivityLogFragment extends Fragment {
     private FragmentActivityLogBinding binding;
@@ -46,6 +56,9 @@ public class ActivityLogFragment extends Fragment {
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Inflates the layout, checks for admin access, and initializes ViewModel and UI components.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -69,12 +82,18 @@ public class ActivityLogFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Triggers initial data loading after the view is created.
+     */
     @Override
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
         viewModel.loadInitialData();
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new ActivityLogAdapter(logList);
         binding.recyclerViewActivityLog.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -97,6 +116,9 @@ public class ActivityLogFragment extends Fragment {
         });
     }
 
+    /**
+     * Sets up filters for logs, including search, role, store, and date range.
+     */
     private void setupFilters() {
         UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter,
                 binding.etSearchLog, binding.spinnerRoleFilter, binding.spinnerStoreFilter);
@@ -123,6 +145,9 @@ public class ActivityLogFragment extends Fragment {
         });
     }
 
+    /**
+     * Displays a date picker dialog and updates the selected start or end date.
+     */
     private void showDatePicker(boolean isStart) {
         Calendar cal = Calendar.getInstance();
         new DatePickerDialog(requireContext(), (view, year, month, day) -> {
@@ -141,12 +166,18 @@ public class ActivityLogFragment extends Fragment {
         }, cal.get(Calendar.YEAR), cal.get(Calendar.MONTH), cal.get(Calendar.DAY_OF_MONTH)).show();
     }
 
+    /**
+     * Handles store selection from the filter spinner.
+     */
     private void onStoreSelected() {
         int pos = binding.spinnerStoreFilter.getSelectedItemPosition();
         Long storeId = (pos > 0 && !storeList.isEmpty()) ? storeList.get(pos - 1).getId() : null;
         viewModel.setStoreFilter(storeId);
     }
 
+    /**
+     * Observes the ViewModel for log list updates, store options, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getLogs().observe(getViewLifecycleOwner(), list -> {
             logList.clear();
@@ -164,6 +195,9 @@ public class ActivityLogFragment extends Fragment {
                 binding.swipeRefreshActivityLog.setRefreshing(loading));
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/AdoptionFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing adoption records.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.graphics.Color;
@@ -44,6 +51,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of adoptions with a calendar view and filtering.
+ */
 @AndroidEntryPoint
 public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdoptionClickListener {
 
@@ -58,12 +68,18 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(AdoptionListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components, calendar, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -88,6 +104,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for adoption list, stores, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getAdoptions().observe(getViewLifecycleOwner(), list -> {
             adoptionList.clear();
@@ -106,6 +125,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         });
     }
 
+    /**
+     * Configures the bulk delete handler for multiple adoption record deletion.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -119,6 +141,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         );
     }
 
+    /**
+     * Reloads adoption data and stores when the fragment resumes.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -126,6 +151,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         if (!isStaff()) viewModel.loadStores();
     }
 
+    /**
+     * Toggles between month and week display modes for the calendar.
+     */
     private void toggleCalendarMode() {
         isMonthMode = !isMonthMode;
         binding.calendarViewAdoption.state().edit()
@@ -133,6 +161,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
                 .commit();
     }
 
+    /**
+     * Sets up the filter visibility toggle, considering user roles.
+     */
     private void setupFilterToggle() {
         if (isStaff()) {
             UIUtils.setupFilterToggle(binding.btnToggleFilterAdoption, binding.layoutFilterAdoption,
@@ -144,10 +175,16 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         }
     }
 
+    /**
+     * Checks if the currently logged-in user has the STAFF role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Configures the calendar view for date-based filtering.
+     */
     private void setupCalendar() {
         binding.calendarViewAdoption.setOnDateChangedListener((widget, date, selected) -> {
             if (selected) {
@@ -164,6 +201,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         });
     }
 
+    /**
+     * Updates calendar decorators to highlight dates with adoptions.
+     */
     private void updateCalendarDecorators() {
         HashSet<CalendarDay> datesWithAdoptions = new HashSet<>();
         for (AdoptionDTO adoption : adoptionList) {
@@ -184,6 +224,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         binding.calendarViewAdoption.addDecorator(new EventDecorator(Color.RED, datesWithAdoptions));
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new AdoptionAdapter(adoptionList, this);
         binding.recyclerViewAdoptions.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -206,23 +249,38 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         });
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchAdoption, () -> loadAdoptions(true));
     }
 
+    /**
+     * Configures the status filter spinner.
+     */
     private void setupStatusFilter() {
         String[] statuses = {"All Statuses", "Completed", "Pending", "Missed", "Cancelled"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerStatusAdoption, statuses, () -> loadAdoptions(true));
     }
 
+    /**
+     * Configures the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStoreAdoption, () -> loadAdoptions(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshAdoption.setOnRefreshListener(() -> loadAdoptions(true));
     }
 
+    /**
+     * Loads adoption data based on current filters, search query, and selected date.
+     */
     private void loadAdoptions(boolean reset) {
         String query = binding.etSearchAdoption.getText().toString().trim();
         String status = binding.spinnerStatusAdoption.getSelectedItem() != null ? binding.spinnerStatusAdoption.getSelectedItem().toString() : "All Statuses";
@@ -250,6 +308,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         viewModel.loadAdoptions(reset, query, status, storeId, selectedDateString, null);
     }
 
+    /**
+     * Navigates to the adoption detail screen.
+     */
     private void openDetail(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -259,9 +320,15 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         NavHostFragment.findNavController(this).navigate(R.id.nav_adoption_detail, args);
     }
 
+    /**
+     * Handles adoption item clicks by opening details.
+     */
     @Override
     public void onAdoptionClick(int position) { openDetail(position); }
 
+    /**
+     * Forwards selection changes to the bulk delete handler.
+     */
     @Override
     public void onSelectionChanged(int selectedCount) {
         if (bulkDeleteHandler != null) {
@@ -269,6 +336,9 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
         }
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/AnalyticsFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for displaying store analytics and charts.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.graphics.Color;
@@ -18,6 +25,9 @@ import java.math.BigDecimal;
 import java.math.RoundingMode;
 import java.util.*;
 
+/**
+ * Fragment for displaying business analytics, including revenue, transactions, and product performance.
+ */
 @AndroidEntryPoint
 public class AnalyticsFragment extends Fragment {
 
@@ -31,6 +41,9 @@ public class AnalyticsFragment extends Fragment {
     private static final String[] TOP_N_OPTIONS = {"5", "10", "15", "20"};
     private static final int[] TOP_N_VALUES    = { 5,   10,   15,   20 };
 
+    /**
+     * Inflates the layout, initializes ViewModel, and sets up UI components and filters.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -51,6 +64,9 @@ public class AnalyticsFragment extends Fragment {
     private static final int COLOR_SELECTED = 0xFF4ECDC4;
     private static final int COLOR_UNSELECTED = 0xFFCBD5E1;
 
+    /**
+     * Configures the view mode toggle buttons (My Analytics vs Store Analytics).
+     */
     private void setupViewModeToggle() {
         updateViewModeButtonStyles(viewModel.getViewMode());
 
@@ -67,6 +83,9 @@ public class AnalyticsFragment extends Fragment {
         });
     }
 
+    /**
+     * Updates the styles of the view mode buttons based on the selected mode.
+     */
     private void updateViewModeButtonStyles(String mode) {
         binding.btnMyAnalytics.setBackgroundTintList(
             android.content.res.ColorStateList.valueOf(mode.equals("mine") ? COLOR_SELECTED : COLOR_UNSELECTED));
@@ -74,6 +93,9 @@ public class AnalyticsFragment extends Fragment {
             android.content.res.ColorStateList.valueOf(mode.equals("store") ? COLOR_SELECTED : COLOR_UNSELECTED));
     }
 
+    /**
+     * Updates the visibility of the store filter based on the user's role and selected view mode.
+     */
     private void updateStoreFilterVisibility(String mode) {
         boolean isAdmin = "ADMIN".equalsIgnoreCase(tokenManager.getRole());
         int vis = (isAdmin && mode.equals("store")) ? View.VISIBLE : View.GONE;
@@ -81,8 +103,10 @@ public class AnalyticsFragment extends Fragment {
         binding.spinnerFilterStore.setVisibility(vis);
     }
 
-    // Filter Panel
 
+    /**
+     * Configures the filter panel, including date pickers, presets, and action buttons.
+     */
     private void setupFilterPanel() {
         SpinnerUtils.setupStringSpinner(requireContext(), binding.spinnerTopN, TOP_N_OPTIONS);
 
@@ -111,12 +135,18 @@ public class AnalyticsFragment extends Fragment {
         binding.btnFilterReset.setOnClickListener(v -> resetFilters());
     }
 
+    /**
+     * Toggles the visibility of the filter content section.
+     */
     private void toggleFilters() {
         filtersExpanded = !filtersExpanded;
         binding.llFilterContent.setVisibility(filtersExpanded ? View.VISIBLE : View.GONE);
         binding.tvFilterToggleIcon.setText(filtersExpanded ? "▲" : "▼");
     }
 
+    /**
+     * Applies a date range preset to the filter fields.
+     */
     private void applyPreset(int startOffset, int endOffset) {
         binding.etFilterStartDate.setText(getDateString(startOffset));
         binding.etFilterEndDate.setText(getDateString(endOffset));
@@ -124,6 +154,9 @@ public class AnalyticsFragment extends Fragment {
         applyFiltersFromUI();
     }
 
+    /**
+     * Reads filter values from the UI and applies them to the ViewModel.
+     */
     private void applyFiltersFromUI() {
         AnalyticsViewModel.FilterState filter = new AnalyticsViewModel.FilterState();
         filter.startDate = binding.etFilterStartDate.getText().toString().trim();
@@ -142,6 +175,9 @@ public class AnalyticsFragment extends Fragment {
         viewModel.applyFilter(filter);
     }
 
+    /**
+     * Resets all filters to their default values.
+     */
     private void resetFilters() {
         binding.etFilterStartDate.setText("");
         binding.etFilterEndDate.setText("");
@@ -152,6 +188,9 @@ public class AnalyticsFragment extends Fragment {
         viewModel.resetFilter();
     }
 
+    /**
+     * Updates the text summary of the currently selected date range.
+     */
     private void updateFilterSummary() {
         String start = binding.etFilterStartDate.getText().toString().trim();
         String end   = binding.etFilterEndDate.getText().toString().trim();
@@ -166,10 +205,16 @@ public class AnalyticsFragment extends Fragment {
         }
     }
 
+    /**
+     * Formats a date string into a shorter version for display.
+     */
     private String shortDate(String date) {
         return (date != null && date.length() >= 10) ? date.substring(5) : date;
     }
 
+    /**
+     * Returns a formatted date string for a given day.
+     */
     private String getDateString(int offsetDays) {
         Calendar c = Calendar.getInstance();
         c.add(Calendar.DAY_OF_YEAR, offsetDays);
@@ -177,8 +222,10 @@ public class AnalyticsFragment extends Fragment {
                 c.get(Calendar.YEAR), c.get(Calendar.MONTH) + 1, c.get(Calendar.DAY_OF_MONTH));
     }
 
-    // ViewModel Observation
 
+    /**
+     * Observes the ViewModel for analytics data, loading status, errors, and filter options.
+     */
     private void observeViewModel() {
         viewModel.getAnalyticsData().observe(getViewLifecycleOwner(), this::computeAndDisplay);
 
@@ -216,14 +263,19 @@ public class AnalyticsFragment extends Fragment {
         });
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
-    // Display
 
+    /**
+     * Computes and displays analytics data in summary cards and bar charts.
+     */
     private void computeAndDisplay(AnalyticsViewModel.AnalyticsData data) {
         if (data == null) return;
 
@@ -312,8 +364,10 @@ public class AnalyticsFragment extends Fragment {
         }
     }
 
-    // Chart Helpers
 
+    /**
+     * Dynamically adds a bar chart row to a given layout container.
+     */
     private void addBarRow(LinearLayout parent, String label, String value, float ratio, String color) {
         if (getContext() == null) return;
         LinearLayout row = new LinearLayout(getContext());
@@ -359,6 +413,9 @@ public class AnalyticsFragment extends Fragment {
         parent.addView(row);
     }
 
+    /**
+     * Adds an empty message row to a given layout container.
+     */
     private void addEmptyRow(LinearLayout parent, String message) {
         if (getContext() == null) return;
         TextView tv = new TextView(getContext());
@@ -368,6 +425,9 @@ public class AnalyticsFragment extends Fragment {
         parent.addView(tv);
     }
 
+    /**
+     * Displays an error message and updates UI to reflect the error state.
+     */
     private void showError(String msg) {
         if (getContext() == null || binding == null) return;
         binding.tvTotalRevenue.setText("Error");

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/AppointmentFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing appointments.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.graphics.Color;
@@ -45,6 +52,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of appointments with calendar integration and filtering.
+ */
 @AndroidEntryPoint
 public class AppointmentFragment extends Fragment implements AppointmentAdapter.OnAppointmentClickListener {
 
@@ -63,6 +73,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
     private Long currentUserId = null;
     private final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd", Locale.getDefault());
 
+    /**
+     * Initializes ViewModels for appointment and authentication data.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -70,6 +83,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         authViewModel = new ViewModelProvider(this).get(AuthViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components, calendar, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -97,6 +113,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for appointment list, stores, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getAppointments().observe(getViewLifecycleOwner(), list -> {
             appointmentList.clear();
@@ -115,6 +134,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         });
     }
 
+    /**
+     * Configures the bulk delete handler for multiple appointment deletion.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -128,6 +150,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         );
     }
 
+    /**
+     * Reloads appointment data and stores when the fragment resumes.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -135,6 +160,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         if (!isStaff()) viewModel.loadStores();
     }
 
+    /**
+     * Toggles between month and week display modes for the calendar.
+     */
     private void toggleCalendarMode() {
         isMonthMode = !isMonthMode;
         binding.calendarView.state().edit()
@@ -142,12 +170,18 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
                 .commit();
     }
 
+    /**
+     * Sets up the "My Appointments" filter button.
+     */
     private void setupMyAppointmentFilter() {
         binding.btnMyAppointments.setOnClickListener(v -> {
             loadAppointmentData(true);
         });
     }
 
+    /**
+     * Loads information about the currently logged-in user.
+     */
     private void loadCurrentUserInfo() {
         authViewModel.getMe().observe(getViewLifecycleOwner(), resource -> {
             if (resource.status == Resource.Status.SUCCESS && resource.data != null) {
@@ -156,6 +190,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         });
     }
 
+    /**
+     * Sets up the filter visibility toggle.
+     */
     private void setupFilterToggle() {
         if (isStaff()) {
             UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchAppointment, binding.spinnerStatus);
@@ -166,6 +203,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         }
     }
 
+    /**
+     * Configures the calendar view for date-based filtering.
+     */
     private void setupCalendar() {
         binding.calendarView.setOnDateChangedListener((widget, date, selected) -> {
             if (selected) {
@@ -182,6 +222,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         });
     }
 
+    /**
+     * Updates calendar decorators to highlight dates with appointments.
+     */
     private void updateCalendarDecorators() {
         HashSet<CalendarDay> datesWithAppointments = new HashSet<>();
         for (AppointmentDTO appointment : appointmentList) {
@@ -200,23 +243,38 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         binding.calendarView.addDecorator(new EventDecorator(Color.RED, datesWithAppointments));
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchAppointment, () -> loadAppointmentData(true));
     }
 
+    /**
+     * Configures the status filter spinner.
+     */
     private void setupStatusFilter() {
         String[] statuses = {"All Statuses", "Booked", "Completed", "Cancelled", "Missed"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerStatus, statuses, () -> loadAppointmentData(true));
     }
 
+    /**
+     * Configures the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStore, () -> loadAppointmentData(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshAppointment.setOnRefreshListener(() -> loadAppointmentData(true));
     }
 
+    /**
+     * Navigates to the appointment detail screen.
+     */
     private void openAppointmentDetails(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -226,11 +284,17 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         NavHostFragment.findNavController(this).navigate(R.id.nav_appointment_detail, args);
     }
 
+    /**
+     * Handles appointment item clicks by opening details.
+     */
     @Override
     public void onAppointmentClick(int position) {
         openAppointmentDetails(position);
     }
 
+    /**
+     * Forwards selection changes to the bulk delete handler.
+     */
     @Override
     public void onSelectionChanged(int count) {
         if (bulkDeleteHandler != null) {
@@ -238,10 +302,16 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         }
     }
 
+    /**
+     * Checks if the currently logged-in user has the STAFF role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Loads appointment data based on current filters, search query, and selected date.
+     */
     private void loadAppointmentData(boolean reset) {
         String query = binding.etSearchAppointment.getText().toString().trim();
         String status = binding.spinnerStatus.getSelectedItem() != null ? binding.spinnerStatus.getSelectedItem().toString() : "All Statuses";
@@ -274,6 +344,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         viewModel.loadAppointments(reset, query, status, storeId, selectedDateString, employeeId);
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new AppointmentAdapter(appointmentList, this);
         binding.recyclerViewAppointments.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -296,6 +369,9 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         });
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/CouponFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing coupons.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -27,6 +34,9 @@ import java.util.List;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of coupons.
+ */
 @AndroidEntryPoint
 public class CouponFragment extends Fragment implements CouponAdapter.OnCouponClickListener {
     private FragmentCouponBinding binding;
@@ -34,6 +44,9 @@ public class CouponFragment extends Fragment implements CouponAdapter.OnCouponCl
     private CouponAdapter adapter;
     private final List<CouponDTO> couponList = new ArrayList<>();
 
+    /**
+     * Inflates the layout, initializes ViewModel, and sets up UI components.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -59,6 +72,9 @@ public class CouponFragment extends Fragment implements CouponAdapter.OnCouponCl
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for coupon list updates and loading status.
+     */
     private void observeViewModel() {
         viewModel.getCoupons().observe(getViewLifecycleOwner(), list -> {
             couponList.clear();
@@ -71,6 +87,9 @@ public class CouponFragment extends Fragment implements CouponAdapter.OnCouponCl
         });
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new CouponAdapter(couponList, this);
         binding.recyclerViewCoupon.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -93,24 +112,39 @@ public class CouponFragment extends Fragment implements CouponAdapter.OnCouponCl
         });
     }
 
+    /**
+     * Configures the status filter spinner.
+     */
     private void setupStatusFilter() {
         String[] statuses = {"All Statuses", "Active", "Inactive"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerStatusCoupon, statuses, () -> applyFilters(true));
     }
 
+    /**
+     * Configures the discount type filter spinner.
+     */
     private void setupTypeFilter() {
         String[] types = {"All Types", "FIXED", "PERCENT"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerTypeCoupon, types, () -> applyFilters(true));
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchCoupon, () -> applyFilters(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshCoupon.setOnRefreshListener(() -> applyFilters(true));
     }
 
+    /**
+     * Applies filters and loads the coupon list.
+     */
     private void applyFilters(boolean reset) {
         String statusStr = binding.spinnerStatusCoupon.getSelectedItem() != null ?
                 binding.spinnerStatusCoupon.getSelectedItem().toString() : "All Statuses";
@@ -122,25 +156,39 @@ public class CouponFragment extends Fragment implements CouponAdapter.OnCouponCl
                 binding.spinnerTypeCoupon.getSelectedItem().toString() : "All Types";
         String discountType = typeStr.equals("All Types") ? null : typeStr;
 
-        viewModel.loadCoupons(reset, active, discountType, null);
+        String search = binding.etSearchCoupon.getText() != null ? binding.etSearchCoupon.getText().toString().trim() : null;
+        if (search != null && search.isEmpty()) search = null;
+        viewModel.loadCoupons(reset, active, discountType, search);
     }
 
+    /**
+     * Navigates to the coupon detail screen.
+     */
     private void openDetail(long id) {
         Bundle args = new Bundle();
         args.putLong("couponId", id);
         Navigation.findNavController(requireView()).navigate(R.id.couponDetailFragment, args);
     }
 
+    /**
+     * Handles coupon item clicks by opening details.
+     */
     @Override
     public void onCouponClick(CouponDTO coupon) {
         openDetail(coupon.getCouponId());
     }
 
+    /**
+     * Shows or hides the bulk delete button based on selection count.
+     */
     @Override
     public void onSelectionChanged(int count) {
         binding.btnBulkDeleteCoupons.setVisibility(count > 0 ? View.VISIBLE : View.GONE);
     }
 
+    /**
+     * Displays a confirmation dialog for deleting multiple coupons.
+     */
     private void confirmBulkDelete() {
         new AlertDialog.Builder(requireContext())
                 .setTitle("Confirm Bulk Delete")

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/CustomerFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing customers.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -22,6 +29,9 @@ import java.util.*;
 import javax.inject.Inject;
 import javax.inject.Named;
 
+/**
+ * Fragment for displaying and managing a list of customers.
+ */
 @AndroidEntryPoint
 public class CustomerFragment extends Fragment implements CustomerAdapter.OnCustomerClickListener {
 
@@ -33,6 +43,9 @@ public class CustomerFragment extends Fragment implements CustomerAdapter.OnCust
     @Inject @Named("baseUrl") String baseUrl;
     @Inject TokenManager tokenManager;
 
+    /**
+     * Inflates the layout, initializes ViewModel, and sets up UI components and filters.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -45,17 +58,21 @@ public class CustomerFragment extends Fragment implements CustomerAdapter.OnCust
         setupSwipeRefresh();
         observeViewModel();
 
+        viewModel.resetFilters();
         viewModel.loadCustomers(true);
 
         binding.fabAddCustomer.setOnClickListener(v -> openDetail(-1));
 
         UIUtils.setupHamburgerMenu(binding.btnHamburgerCustomer, this);
         UIUtils.setupFilterToggle(binding.btnToggleFilterCustomer, binding.layoutFilterCustomer,
-                binding.etSearchCustomer, binding.spinnerStatusCustomer);
+                binding.etSearchCustomer, this::applyFilters, binding.spinnerStatusCustomer);
 
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for customer list updates and loading status.
+     */
     private void observeViewModel() {
         viewModel.getFilteredCustomers().observe(getViewLifecycleOwner(), list -> {
             customerList.clear();
@@ -68,6 +85,9 @@ public class CustomerFragment extends Fragment implements CustomerAdapter.OnCust
         });
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new CustomerAdapter(customerList, this);
         adapter.setBaseUrl(baseUrl);
@@ -92,15 +112,24 @@ public class CustomerFragment extends Fragment implements CustomerAdapter.OnCust
         });
     }
 
+    /**
+     * Configures the status filter spinner.
+     */
     private void setupStatusFilter() {
         String[] statuses = {"All Statuses", "Active", "Inactive"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerStatusCustomer, statuses, this::applyFilters);
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchCustomer, this::applyFilters);
     }
 
+    /**
+     * Applies filters and triggers data reloading or filtering in ViewModel.
+     */
     private void applyFilters() {
         String query = binding.etSearchCustomer.getText().toString().trim();
         String status = binding.spinnerStatusCustomer.getSelectedItem() != null ?
@@ -108,10 +137,16 @@ public class CustomerFragment extends Fragment implements CustomerAdapter.OnCust
         viewModel.filter(query, status);
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshCustomer.setOnRefreshListener(() -> viewModel.loadCustomers(true));
     }
 
+    /**
+     * Navigates to the customer detail screen.
+     */
     private void openDetail(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -129,11 +164,17 @@ public class CustomerFragment extends Fragment implements CustomerAdapter.OnCust
         NavHostFragment.findNavController(this).navigate(R.id.nav_customer_detail, args);
     }
 
+    /**
+     * Handles customer item clicks by opening details.
+     */
     @Override
     public void onCustomerClick(int position) {
         openDetail(position);
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/InventoryFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing inventory items.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -32,6 +39,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing inventory items.
+ */
 @AndroidEntryPoint
 public class InventoryFragment extends Fragment implements InventoryAdapter.OnInventoryClickListener {
 
@@ -43,12 +53,18 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(InventoryListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components, filters, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -71,6 +87,9 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for inventory list updates, store list, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getInventory().observe(getViewLifecycleOwner(), list -> {
             inventoryList.clear();
@@ -88,6 +107,9 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         });
     }
 
+    /**
+     * Configures the bulk delete handler for multiple inventory item deletion.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -101,18 +123,27 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         );
     }
 
+    /**
+     * Reloads store data if necessary when the fragment resumes.
+     */
     @Override
     public void onResume() {
         super.onResume();
         if (!isStaff()) viewModel.loadStores();
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Sets up the filter visibility toggle, considering user roles.
+     */
     private void setupFilterToggle() {
         if (isStaff()) {
             UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchInventory);
@@ -122,18 +153,30 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         }
     }
 
+    /**
+     * Checks if the currently logged-in user has the STAFF role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchInventory, () -> loadInventory(true));
     }
 
+    /**
+     * Configures the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStore, () -> loadInventory(true));
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new InventoryAdapter(inventoryList, this);
         binding.recyclerViewInventory.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -156,10 +199,16 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         });
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshInventory.setOnRefreshListener(() -> loadInventory(true));
     }
 
+    /**
+     * Loads inventory data based on current search query and store filter.
+     */
     private void loadInventory(boolean reset) {
         String query = binding.etSearchInventory != null ? binding.etSearchInventory.getText().toString().trim() : "";
         if (query.isEmpty()) query = null;
@@ -178,6 +227,9 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         viewModel.loadInventory(reset, query, storeId);
     }
 
+    /**
+     * Navigates to the inventory detail screen.
+     */
     private void openDetail(InventoryDTO inv) {
         Bundle args = new Bundle();
         if (inv != null) {
@@ -186,6 +238,9 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         NavHostFragment.findNavController(this).navigate(R.id.nav_inventory_detail, args);
     }
 
+    /**
+     * Handles inventory item clicks by opening details.
+     */
     @Override
     public void onInventoryClick(int position) {
         if (position >= 0 && position < inventoryList.size()) {
@@ -193,6 +248,9 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
         }
     }
 
+    /**
+     * Forwards selection changes to the bulk delete handler.
+     */
     @Override
     public void onSelectionChanged(int selectedCount) {
         if (bulkDeleteHandler != null) {

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/PetFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing pets.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -33,6 +40,9 @@ import javax.inject.Named;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of pets.
+ */
 @AndroidEntryPoint
 public class PetFragment extends Fragment implements PetAdapter.OnPetClickListener {
     private FragmentPetBinding binding;
@@ -44,12 +54,18 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
     @Inject @Named("baseUrl") String baseUrl;
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the view model.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(PetListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and initializes UI components and filters.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -72,6 +88,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         return binding.getRoot();
     }
 
+    /**
+     * Observes LiveData from the ViewModel to update the list and filter options.
+     */
     private void observeViewModel() {
         viewModel.getPets().observe(getViewLifecycleOwner(), list -> {
             petList.clear();
@@ -94,6 +113,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         });
     }
 
+    /**
+     * Configures the handler for bulk deletion of pets.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -107,6 +129,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         );
     }
 
+    /**
+     * Refreshes pet data and filters when the fragment is resumed.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -115,6 +140,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         if (!isStaff()) viewModel.loadStores();
     }
 
+    /**
+     * Sets up the visibility of filters based on the user's role.
+     */
     private void setupFilterToggle() {
         if (isStaff()) {
             UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchPet,
@@ -126,32 +154,53 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         }
     }
 
+    /**
+     * Checks if the current user has the 'STAFF' role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Attaches search functionality to the search input field.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchPet, () -> loadPetData(true));
     }
 
+    /**
+     * Initializes the status filter spinner.
+     */
     private void setupStatusFilter() {
         String[] statuses = {"All Statuses", "Available", "Adopted", "Owned", "Pending"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerStatus, statuses, () -> loadPetData(true));
     }
 
+    /**
+     * Initializes the species filter spinner.
+     */
     private void setupSpeciesFilter() {
         String[] initial = {"All Species"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerSpecies, initial, () -> loadPetData(true));
     }
 
+    /**
+     * Initializes the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStore, () -> loadPetData(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshPet.setOnRefreshListener(() -> loadPetData(true));
     }
 
+    /**
+     * Triggers loading of pet data from the backend with current filters.
+     */
     private void loadPetData(boolean reset) {
         String query = binding.etSearchPet.getText().toString().trim();
         String status = binding.spinnerStatus.getSelectedItem() != null ? binding.spinnerStatus.getSelectedItem().toString() : "All Statuses";
@@ -171,6 +220,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         viewModel.loadPets(reset, query, status, species, storeId);
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new PetAdapter(petList, this);
         adapter.setBaseUrl(baseUrl);
@@ -195,6 +247,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         });
     }
 
+    /**
+     * Navigates to the profile view of a specific pet.
+     */
     private void openPetProfile(int position) {
         Bundle args = new Bundle();
         PetDTO pet = petList.get(position);
@@ -202,15 +257,24 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         NavHostFragment.findNavController(this).navigate(R.id.nav_pet_profile, args);
     }
 
+    /**
+     * Navigates to the screen for adding a new pet.
+     */
     private void openPetDetails() {
         NavHostFragment.findNavController(this).navigate(R.id.nav_pet_detail);
     }
 
+    /**
+     * Handles clicks on individual pets in the list.
+     */
     @Override
     public void onPetClick(int position) {
         openPetProfile(position);
     }
 
+    /**
+     * Notifies the bulk delete handler when item selection changes.
+     */
     @Override
     public void onSelectionChanged(int selectedCount) {
         if (bulkDeleteHandler != null) {
@@ -218,6 +282,9 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
         }
     }
 
+    /**
+     * Cleans up the binding when the view is destroyed.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/ProductFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing products.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -31,6 +38,9 @@ import javax.inject.Named;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of products.
+ */
 @AndroidEntryPoint
 public class ProductFragment extends Fragment implements ProductAdapter.OnProductClickListener {
 
@@ -41,12 +51,18 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
 
     @Inject @Named("baseUrl") String baseUrl;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(ProductListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -66,6 +82,9 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for product list, categories, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getProducts().observe(getViewLifecycleOwner(), list -> {
             productList.clear();
@@ -83,6 +102,9 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         });
     }
 
+    /**
+     * Reloads product data and categories when the fragment resumes.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -90,23 +112,38 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         viewModel.loadCategories();
     }
 
+    /**
+     * Sets up the filter visibility toggle.
+     */
     private void setupFilterToggle() {
         UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter,
                 binding.etSearchProduct, binding.spinnerCategory);
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchProduct, () -> loadProductData(true));
     }
 
+    /**
+     * Configures the category filter spinner.
+     */
     private void setupCategoryFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerCategory, () -> loadProductData(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshProduct.setOnRefreshListener(() -> loadProductData(true));
     }
 
+    /**
+     * Loads product data based on current filters and search query.
+     */
     private void loadProductData(boolean reset) {
         String query = binding.etSearchProduct.getText().toString().trim();
         if (query.isEmpty()) query = null;
@@ -120,6 +157,9 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         viewModel.loadProducts(reset, query, categoryId);
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new ProductAdapter(productList, this);
         adapter.setBaseUrl(baseUrl);
@@ -143,6 +183,9 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         });
     }
 
+    /**
+     * Navigates to the product detail screen.
+     */
     private void openProductDetails(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -152,11 +195,17 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         NavHostFragment.findNavController(this).navigate(R.id.nav_product_detail, args);
     }
 
+    /**
+     * Handles product item clicks by opening details.
+     */
     @Override
     public void onProductClick(int position) {
         openProductDetails(position);
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/ProductSupplierFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing product-supplier links.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -29,6 +36,9 @@ import java.util.List;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing the relationships between products and suppliers.
+ */
 @AndroidEntryPoint
 public class ProductSupplierFragment extends Fragment
         implements ProductSupplierAdapter.OnProductSupplierClickListener {
@@ -40,12 +50,18 @@ public class ProductSupplierFragment extends Fragment
     private ProductSupplierListViewModel viewModel;
     private BulkDeleteHandler bulkDeleteHandler;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(ProductSupplierListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components, filters, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -67,6 +83,9 @@ public class ProductSupplierFragment extends Fragment
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for product-supplier list, products, suppliers, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getProductSuppliers().observe(getViewLifecycleOwner(), list -> {
             psList.clear();
@@ -89,6 +108,9 @@ public class ProductSupplierFragment extends Fragment
         });
     }
 
+    /**
+     * Configures the bulk delete handler for multiple product-supplier relationship deletion.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -102,6 +124,9 @@ public class ProductSupplierFragment extends Fragment
         );
     }
 
+    /**
+     * Reloads data and filter options when the fragment resumes.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -109,17 +134,26 @@ public class ProductSupplierFragment extends Fragment
         viewModel.loadFilterData();
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Sets up the filter visibility toggle.
+     */
     private void setupFilterToggle() {
         UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchPS,
                 binding.spinnerProduct, binding.spinnerSupplier);
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new ProductSupplierAdapter(psList, this);
         binding.recyclerViewPS.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -142,22 +176,37 @@ public class ProductSupplierFragment extends Fragment
         });
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchPS, () -> loadData(true));
     }
 
+    /**
+     * Configures the product filter spinner.
+     */
     private void setupProductFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerProduct, () -> loadData(true));
     }
 
+    /**
+     * Configures the supplier filter spinner.
+     */
     private void setupSupplierFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerSupplier, () -> loadData(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshPS.setOnRefreshListener(() -> loadData(true));
     }
 
+    /**
+     * Loads product-supplier data based on current search query and filters.
+     */
     private void loadData(boolean reset) {
         String query = binding.etSearchPS.getText().toString().trim();
         if (query.isEmpty()) query = null;
@@ -177,6 +226,9 @@ public class ProductSupplierFragment extends Fragment
         viewModel.loadProductSuppliers(reset, query, productId, supplierId);
     }
 
+    /**
+     * Navigates to the product-supplier detail screen.
+     */
     private void openDetail(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -187,9 +239,15 @@ public class ProductSupplierFragment extends Fragment
         NavHostFragment.findNavController(this).navigate(R.id.nav_product_supplier_detail, args);
     }
 
+    /**
+     * Handles product-supplier item clicks by opening details.
+     */
     @Override
     public void onProductSupplierClick(int position) { openDetail(position); }
 
+    /**
+     * Forwards selection changes to the bulk delete handler.
+     */
     @Override
     public void onSelectionChanged(int count) {
         if (bulkDeleteHandler != null) {

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/PurchaseOrderFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing purchase orders.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -30,6 +37,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of purchase orders.
+ */
 @AndroidEntryPoint
 public class PurchaseOrderFragment extends Fragment
         implements PurchaseOrderAdapter.OnPurchaseOrderClickListener {
@@ -41,12 +51,18 @@ public class PurchaseOrderFragment extends Fragment
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(PurchaseOrderListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components, filters, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -64,6 +80,9 @@ public class PurchaseOrderFragment extends Fragment
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for purchase order list, stores, and loading status.
+     */
     private void observeViewModel() {
         viewModel.getPurchaseOrders().observe(getViewLifecycleOwner(), list -> {
             poList.clear();
@@ -81,6 +100,9 @@ public class PurchaseOrderFragment extends Fragment
         });
     }
 
+    /**
+     * Reloads data and stores if necessary when the fragment resumes.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -88,6 +110,9 @@ public class PurchaseOrderFragment extends Fragment
         if (!isStaff()) viewModel.loadStores();
     }
 
+    /**
+     * Sets up the filter visibility toggle
+     */
     private void setupFilterToggle() {
         if (isStaff()) {
             UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchPO);
@@ -97,18 +122,30 @@ public class PurchaseOrderFragment extends Fragment
         }
     }
 
+    /**
+     * Checks if the currently logged-in user has the STAFF role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchPO, () -> loadData(true));
     }
 
+    /**
+     * Configures the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStore, () -> loadData(true));
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new PurchaseOrderAdapter(poList, this);
         binding.recyclerViewPO.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -131,10 +168,16 @@ public class PurchaseOrderFragment extends Fragment
         });
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshPO.setOnRefreshListener(() -> loadData(true));
     }
 
+    /**
+     * Loads purchase order data based on current search query and store filter.
+     */
     private void loadData(boolean reset) {
         String query = binding.etSearchPO != null ? binding.etSearchPO.getText().toString().trim() : "";
         if (query.isEmpty()) query = null;
@@ -153,6 +196,9 @@ public class PurchaseOrderFragment extends Fragment
         viewModel.loadPurchaseOrders(reset, query, storeId);
     }
 
+    /**
+     * Navigates to the purchase order detail screen.
+     */
     private void openDetail(int position) {
         Bundle args = new Bundle();
         PurchaseOrderDTO po = poList.get(position);
@@ -160,11 +206,17 @@ public class PurchaseOrderFragment extends Fragment
         NavHostFragment.findNavController(this).navigate(R.id.nav_purchase_order_detail, args);
     }
 
+    /**
+     * Handles purchase order item clicks by opening details.
+     */
     @Override
     public void onPurchaseOrderClick(int position) {
         openDetail(position);
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/SaleFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing sales.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -31,6 +38,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of sales.
+ */
 @AndroidEntryPoint
 public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickListener {
 
@@ -41,6 +51,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Inflates the layout for this fragment.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -48,6 +61,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         return binding.getRoot();
     }
 
+    /**
+     * Initializes UI components and observers after the view is created.
+     */
     @Override
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
@@ -79,6 +95,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
                 NavHostFragment.findNavController(this).navigate(R.id.nav_refund));
     }
 
+    /**
+     * Observes LiveData from the ViewModel to update the list and filter options.
+     */
     private void observeViewModel() {
         viewModel.getSales().observe(getViewLifecycleOwner(), list -> {
             saleList.clear();
@@ -101,6 +120,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         });
     }
 
+    /**
+     * Refreshes lookup data when the fragment is resumed.
+     */
     @Override
     public void onResume() {
         super.onResume();
@@ -108,6 +130,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         viewModel.loadCustomers();
     }
 
+    /**
+     * Sets up the visibility of filters.
+     */
     private void setupFilterToggle() {
         if (isStaff()) {
             UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchSale,
@@ -119,32 +144,53 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         }
     }
 
+    /**
+     * Checks if the current user has the 'STAFF' role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Checks if the current user has the 'ADMIN' role.
+     */
     private boolean isAdmin() {
         return "ADMIN".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Initializes the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStore, () -> loadSales(true));
     }
 
+    /**
+     * Initializes the payment method filter spinner.
+     */
     private void setupPaymentMethodFilter() {
         String[] paymentMethods = {"All Payments", "Cash", "Card"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerPaymentMethod, paymentMethods, () -> loadSales(true));
     }
 
+    /**
+     * Initializes the refund status filter spinner.
+     */
     private void setupRefundStatusFilter() {
         String[] refundStatuses = {"All Status", "Sale", "Refund"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerRefundStatus, refundStatuses, () -> loadSales(true));
     }
 
+    /**
+     * Initializes the customer filter spinner.
+     */
     private void setupCustomerFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerCustomer, () -> loadSales(true));
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new SaleAdapter(saleList, this);
         binding.recyclerViewSales.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -168,14 +214,23 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         });
     }
 
+    /**
+     * Attaches search functionality to the search input field.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchSale, () -> loadSales(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshSale.setOnRefreshListener(() -> loadSales(true));
     }
 
+    /**
+     * Triggers loading of sale data from the backend with current filters.
+     */
     private void loadSales(boolean reset) {
         String query = binding.etSearchSale != null ? binding.etSearchSale.getText().toString().trim() : "";
         if (query.isEmpty()) query = null;
@@ -210,6 +265,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         viewModel.loadSales(reset, query, paymentMethod, storeId, isRefund, customerId);
     }
 
+    /**
+     * Handles clicks on individual sales in the list.
+     */
     @Override
     public void onSaleClick(int position) {
         if (position < 0 || position >= saleList.size()) return;
@@ -225,6 +283,9 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
         NavHostFragment.findNavController(this).navigate(R.id.nav_sale_detail, args);
     }
 
+    /**
+     * Cleans up the binding when the view is destroyed.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/ServiceFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing services.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -39,12 +46,18 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
     private ServiceListViewModel viewModel;
     private BulkDeleteHandler bulkDeleteHandler;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(ServiceListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -67,6 +80,9 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for service list updates and loading status.
+     */
     private void observeViewModel() {
         viewModel.getServices().observe(getViewLifecycleOwner(), list -> {
             serviceList.clear();
@@ -79,6 +95,9 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
         });
     }
 
+    /**
+     * Configures the bulk delete handler for multiple service deletion.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -92,20 +111,32 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
         );
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Sets up the filter visibility toggle.
+     */
     private void setupFilterToggle() {
         UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchService);
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchService, () -> loadServices(true));
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new ServiceAdapter(serviceList, this);
         binding.recyclerViewServices.setLayoutManager(new LinearLayoutManager(getContext()));
@@ -128,16 +159,25 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
         });
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshService.setOnRefreshListener(() -> loadServices(true));
     }
 
+    /**
+     * Loads service data based on current filters and search query.
+     */
     private void loadServices(boolean reset) {
         String query = binding.etSearchService.getText().toString().trim();
         if (query.isEmpty()) query = null;
         viewModel.loadServices(reset, query);
     }
 
+    /**
+     * Navigates to the service detail screen.
+     */
     private void openDetail(ServiceDTO service) {
         Bundle args = new Bundle();
         if (service != null) {
@@ -146,6 +186,9 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
         NavHostFragment.findNavController(this).navigate(R.id.nav_service_detail, args);
     }
 
+    /**
+     * Handles service item clicks by opening details.
+     */
     @Override
     public void onServiceClick(int position) {
         if (position >= 0 && position < serviceList.size()) {
@@ -153,6 +196,9 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
         }
     }
 
+    /**
+     * Forwards selection changes to the bulk delete handler.
+     */
     @Override
     public void onSelectionChanged(int count) {
         if (bulkDeleteHandler != null) {

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/StaffFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing staff members.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -24,6 +31,9 @@ import java.util.*;
 import javax.inject.Inject;
 import javax.inject.Named;
 
+/**
+ * Fragment for displaying and managing a list of staff members.
+ */
 @AndroidEntryPoint
 public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmployeeClickListener {
 
@@ -35,6 +45,9 @@ public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmploye
     @Inject @Named("baseUrl") String baseUrl;
     @Inject TokenManager tokenManager;
 
+    /**
+     * Inflates the layout and initializes UI components, filters, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -60,6 +73,9 @@ public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmploye
         return binding.getRoot();
     }
 
+    /**
+     * Observes LiveData from the ViewModel to update the list and filter options.
+     */
     private void observeViewModel() {
         viewModel.getFilteredEmployees().observe(getViewLifecycleOwner(), list -> {
             staffList.clear();
@@ -77,6 +93,9 @@ public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmploye
         });
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new EmployeeAdapter(staffList, this);
         adapter.setBaseUrl(baseUrl);
@@ -101,19 +120,31 @@ public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmploye
         });
     }
 
+    /**
+     * Initializes the status filter spinner.
+     */
     private void setupStatusFilter() {
         String[] statuses = {"All Statuses", "Active", "Inactive"};
         SpinnerUtils.setupStringFilterSpinner(requireContext(), binding.spinnerStatusStaff, statuses, this::applyFilters);
     }
 
+    /**
+     * Initializes the store filter spinner.
+     */
     private void setupStoreFilter() {
         SpinnerUtils.setupFilterSpinner(binding.spinnerStoreStaff, this::applyFilters);
     }
 
+    /**
+     * Attaches search functionality to the search input field.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchStaff, this::applyFilters);
     }
 
+    /**
+     * Applies the selected filters and triggers a data reload from the view model.
+     */
     private void applyFilters() {
         String query = binding.etSearchStaff.getText().toString().trim();
         String status = binding.spinnerStatusStaff.getSelectedItem() != null ?
@@ -128,10 +159,16 @@ public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmploye
         viewModel.filter(query, storeId, status);
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshStaff.setOnRefreshListener(() -> viewModel.loadStaff(true));
     }
 
+    /**
+     * Navigates to the staff detail screen for adding or editing an employee.
+     */
     private void openDetail(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -149,11 +186,17 @@ public class StaffFragment extends Fragment implements EmployeeAdapter.OnEmploye
         NavHostFragment.findNavController(this).navigate(R.id.nav_staff_detail, args);
     }
 
+    /**
+     * Handles clicks on individual staff members in the list.
+     */
     @Override
     public void onEmployeeClick(int position) {
         openDetail(position);
     }
 
+    /**
+     * Cleans up the binding when the view is destroyed.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/SupplierFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Fragment for browsing suppliers.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments;
 
 import android.os.Bundle;
@@ -27,6 +34,9 @@ import java.util.List;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and managing a list of suppliers.
+ */
 @AndroidEntryPoint
 public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupplierClickListener {
 
@@ -36,12 +46,18 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
     private SupplierListViewModel viewModel;
     private BulkDeleteHandler bulkDeleteHandler;
 
+    /**
+     * Initializes the ViewModel.
+     */
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(SupplierListViewModel.class);
     }
 
+    /**
+     * Inflates the layout and sets up UI components, bulk delete, and observers.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -63,6 +79,9 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
         return binding.getRoot();
     }
 
+    /**
+     * Observes the ViewModel for supplier list updates and loading status.
+     */
     private void observeViewModel() {
         viewModel.getSuppliers().observe(getViewLifecycleOwner(), list -> {
             supplierList.clear();
@@ -75,6 +94,9 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
         });
     }
 
+    /**
+     * Configures the bulk delete handler for multiple supplier deletion.
+     */
     private void setupBulkDelete() {
         bulkDeleteHandler = new BulkDeleteHandler(
                 this,
@@ -88,24 +110,39 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
         );
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Sets up the filter visibility toggle.
+     */
     private void setupFilterToggle() {
         UIUtils.setupFilterToggle(binding.btnToggleFilter, binding.layoutFilter, binding.etSearchSupplier);
     }
 
+    /**
+     * Sets up the search input listener.
+     */
     private void setupSearch() {
         UIUtils.attachSearch(binding.etSearchSupplier, () -> loadSupplierData(true));
     }
 
+    /**
+     * Configures the swipe-to-refresh layout.
+     */
     private void setupSwipeRefresh() {
         binding.swipeRefreshSupplier.setOnRefreshListener(() -> loadSupplierData(true));
     }
 
+    /**
+     * Navigates to the supplier detail screen.
+     */
     private void openSupplierDetails(int position) {
         Bundle args = new Bundle();
         if (position != -1) {
@@ -115,11 +152,17 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
         NavHostFragment.findNavController(this).navigate(R.id.nav_supplier_detail, args);
     }
 
+    /**
+     * Handles supplier item clicks by opening details.
+     */
     @Override
     public void onSupplierClick(int position) {
         openSupplierDetails(position);
     }
 
+    /**
+     * Forwards selection changes to the bulk delete handler.
+     */
     @Override
     public void onSelectionChanged(int count) {
         if (bulkDeleteHandler != null) {
@@ -127,12 +170,18 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
         }
     }
 
+    /**
+     * Loads supplier data based on current search query.
+     */
     private void loadSupplierData(boolean reset) {
         String query = binding.etSearchSupplier != null ? binding.etSearchSupplier.getText().toString().trim() : "";
         if (query.isEmpty()) query = null;
         viewModel.loadSuppliers(reset, query);
     }
 
+    /**
+     * Configures the RecyclerView and its scroll listener for pagination.
+     */
     private void setupRecyclerView() {
         adapter = new SupplierAdapter(supplierList, this);
         binding.recyclerViewSuppliers.setLayoutManager(new LinearLayoutManager(getContext()));

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/AdoptionDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single adoption.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.os.Bundle;
@@ -39,12 +46,18 @@ public class AdoptionDetailFragment extends Fragment {
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the fragment and its ViewModel.
+     */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(AdoptionDetailViewModel.class);
     }
 
+    /**
+     * Inflates the layout for the fragment
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -52,6 +65,9 @@ public class AdoptionDetailFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Sets up UI components, observers, and loads initial data after the view is created.
+     */
     @Override
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
@@ -68,6 +84,9 @@ public class AdoptionDetailFragment extends Fragment {
         binding.btnDeleteAdoption.setOnClickListener(v -> confirmDelete());
     }
 
+    /**
+     * Sets up observers for ViewModel to update the UI dynamically.
+     */
     private void observeViewModel() {
         viewModel.getViewState().observe(getViewLifecycleOwner(), this::applyViewState);
 
@@ -113,18 +132,27 @@ public class AdoptionDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Shows or hides the loading bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Initializes the spinners with data and selection listeners.
+     */
     private void setupSpinners() {
         SpinnerUtils.setupStringSpinner(requireContext(), binding.spinnerAdoptionStatus, new String[]{});
 
@@ -141,11 +169,17 @@ public class AdoptionDetailFragment extends Fragment {
         SpinnerUtils.setOnIndexSelectedListener(binding.spinnerAdoptionStatus, p -> notifyDateStatusChange());
     }
 
+    /**
+     * Configures the date picker for the adoption date field.
+     */
     private void setupDatePicker() {
         binding.etAdoptionDate.setOnClickListener(v ->
                 UIUtils.showDatePicker(requireContext(), binding.etAdoptionDate, this::notifyDateStatusChange));
     }
 
+    /**
+     * Notifies the ViewModel when the date or status changes to update available options.
+     */
     private void notifyDateStatusChange() {
         if (isUpdatingUI) return;
         String date = binding.etAdoptionDate.getText().toString();
@@ -154,6 +188,9 @@ public class AdoptionDetailFragment extends Fragment {
         viewModel.onDateChanged(date, status);
     }
 
+    /**
+     * Uses fragment arguments to determine if we are editing an existing record.
+     */
     private void handleArguments() {
         Bundle a = getArguments();
         if (a != null && a.containsKey("adoptionId")) {
@@ -164,6 +201,9 @@ public class AdoptionDetailFragment extends Fragment {
         viewModel.setAdoptionId(-1);
     }
 
+    /**
+     * Load the adoption data from the backend.
+     */
     private void loadAdoptionData() {
         viewModel.loadAdoption().observe(getViewLifecycleOwner(), resource -> {
             if (resource == null) return;
@@ -174,6 +214,10 @@ public class AdoptionDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Applies the current ViewState to the UI elements.
+     * This handles enabling/disabling views and setting text/selections based on state.
+     */
     private void applyViewState(AdoptionDetailViewModel.ViewState state) {
         isUpdatingUI = true;
 
@@ -224,10 +268,16 @@ public class AdoptionDetailFragment extends Fragment {
         isUpdatingUI = false;
     }
 
+    /**
+     * Checks if the currently logged-in user has the STAFF role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Validates input and saves the adoption record.
+     */
     private void saveAdoption() {
         if (!InputValidator.isSpinnerSelected(binding.spinnerAdoptionCustomer, "Customer")) return;
         if (!InputValidator.isSpinnerSelected(binding.spinnerAdoptionPet, "Pet")) return;
@@ -275,6 +325,9 @@ public class AdoptionDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Displays a confirmation dialog before deleting the adoption record.
+     */
     private void confirmDelete() {
         DialogUtils.showDeleteConfirmDialog(requireContext(), "Adoption Record", () ->
                 viewModel.deleteAdoption().observe(getViewLifecycleOwner(), resource -> {
@@ -289,6 +342,9 @@ public class AdoptionDetailFragment extends Fragment {
                 }));
     }
 
+    /**
+     * Navigates back to the previous screen.
+     */
     private void navigateBack() {
         NavHostFragment.findNavController(this).popBackStack();
     }

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/AppointmentDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single appointment.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.os.Bundle;
@@ -47,18 +54,27 @@ public class AppointmentDetailFragment extends Fragment {
 
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the fragment and its ViewModel.
+     */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(AppointmentDetailViewModel.class);
     }
 
+    /**
+     * Inflates the layout for the fragment
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
         binding = FragmentAppointmentDetailBinding.inflate(inflater, container, false);
         return binding.getRoot();
     }
 
+    /**
+     * Sets up UI components, observers, and loads initial data after the view is created.
+     */
     @Override
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
@@ -73,12 +89,18 @@ public class AppointmentDetailFragment extends Fragment {
         binding.btnDeleteAppointment.setOnClickListener(v -> confirmDelete());
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Initializes the spinners with data and selection listeners.
+     */
     private void setupSpinners() {
         SpinnerUtils.setupStringSpinner(requireContext(), binding.spinnerAppointmentStatus, new String[]{});
 
@@ -108,11 +130,17 @@ public class AppointmentDetailFragment extends Fragment {
         SpinnerUtils.setOnIndexSelectedListener(binding.spinnerAppointmentStatus, p -> notifyDateTimeStatusChange());
     }
 
+    /**
+     * Configures the date picker for the appointment date field.
+     */
     private void setupDatePicker() {
         binding.etAppointmentDate.setOnClickListener(v ->
                 UIUtils.showDatePicker(requireContext(), binding.etAppointmentDate, this::notifyDateTimeStatusChange));
     }
 
+    /**
+     * Sets up observers for ViewModel to update the UI dynamically.
+     */
     private void observeViewModel() {
         viewModel.getViewState().observe(getViewLifecycleOwner(), this::applyViewState);
 
@@ -147,12 +175,19 @@ public class AppointmentDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Shows or hides the loading bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null && binding.progressBar != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Applies the current ViewState to the UI elements.
+     * This handles enabling/disabling views and setting text/selections based on state.
+     */
     private void applyViewState(AppointmentDetailViewModel.ViewState state) {
         isUpdatingUI = true;
 
@@ -201,10 +236,16 @@ public class AppointmentDetailFragment extends Fragment {
         isUpdatingUI = false;
     }
 
+    /**
+     * Checks if the currently logged-in user has the STAFF role.
+     */
     private boolean isStaff() {
         return "STAFF".equalsIgnoreCase(tokenManager.getRole());
     }
 
+    /**
+     * Notifies the ViewModel when the date, time, or status changes to update available options.
+     */
     private void notifyDateTimeStatusChange() {
         if (isUpdatingUI) return;
 
@@ -215,6 +256,9 @@ public class AppointmentDetailFragment extends Fragment {
         viewModel.onDateOrTimeChanged(date, time, status);
     }
 
+    /**
+     * Uses fragment arguments to determine if we are editing an existing record.
+     */
     private void handleArguments() {
         Bundle a = getArguments();
         if (a != null && a.containsKey("appointmentId")) {
@@ -225,6 +269,9 @@ public class AppointmentDetailFragment extends Fragment {
         }
     }
 
+    /**
+     * Load the appointment data from the backend.
+     */
     private void loadAppointmentData() {
         viewModel.loadAppointment().observe(getViewLifecycleOwner(), resource -> {
             if (resource == null) return;
@@ -244,6 +291,9 @@ public class AppointmentDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Validates input and saves the appointment record.
+     */
     private void saveAppointment() {
         if (!validateRequiredFields()) return;
 
@@ -275,6 +325,9 @@ public class AppointmentDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Validates that all required fields are selected or filled.
+     */
     private boolean validateRequiredFields() {
         if (!InputValidator.isSpinnerSelected(binding.spinnerCustomer, "Customer")) return false;
         if (!InputValidator.isSpinnerSelected(binding.spinnerStore, "Store")) return false;
@@ -284,15 +337,24 @@ public class AppointmentDetailFragment extends Fragment {
         return true;
     }
 
+    /**
+     * Formats the selected hour and minute from spinners into a time string.
+     */
     private String buildTimeString() {
         return DateTimeUtils.formatTime(HOURS[binding.spinnerHour.getSelectedItemPosition()], MINUTES[binding.spinnerMinute.getSelectedItemPosition()]);
     }
 
+    /**
+     * Handles errors that occur during the save process.
+     */
     private void handleSaveError(String errorMessage) {
         if (errorMessage != null && errorMessage.toLowerCase().contains("not available")) showNoAvailabilityDialog();
         else Toast.makeText(getContext(), errorMessage != null ? errorMessage : "Error saving", Toast.LENGTH_SHORT).show();
     }
 
+    /**
+     * Displays a dialog when the selected time slot is not available.
+     */
     private void showNoAvailabilityDialog() {
         new androidx.appcompat.app.AlertDialog.Builder(requireContext())
                 .setTitle("No Availability")
@@ -301,6 +363,9 @@ public class AppointmentDetailFragment extends Fragment {
                 .setNegativeButton("Cancel Booking", (d, w) -> navigateBack()).show();
     }
 
+    /**
+     * Displays a confirmation dialog before deleting the appointment record.
+     */
     private void confirmDelete() {
         DialogUtils.showDeleteConfirmDialog(requireContext(), "Appointment", () ->
                 viewModel.deleteAppointment().observe(getViewLifecycleOwner(), resource -> {
@@ -310,10 +375,16 @@ public class AppointmentDetailFragment extends Fragment {
                 }));
     }
 
+    /**
+     * Navigates back to the previous screen.
+     */
     private void navigateBack() {
         NavHostFragment.findNavController(this).popBackStack();
     }
 
+    /**
+     * Parses a time string and sets the hour and minute spinners accordingly.
+     */
     private void parseAndSetTimeSpinners(String time) {
         int[] parsedTime = DateTimeUtils.parseTimeString(time);
         if (parsedTime == null) return;

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/CouponDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single coupon.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.os.Bundle;
@@ -29,12 +36,18 @@ import java.util.Locale;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and editing coupon details.
+ */
 @AndroidEntryPoint
 public class CouponDetailFragment extends Fragment {
     private FragmentCouponDetailBinding binding;
     private CouponDetailViewModel viewModel;
     private long couponId = -1;
 
+    /**
+     * Inflates the layout, initializes ViewModel, and sets up UI components.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -74,10 +87,16 @@ public class CouponDetailFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Initializes the discount type spinner with options.
+     */
     private void setupDiscountTypeSpinner() {
         SpinnerUtils.setupStringSpinner(requireContext(), binding.spinnerDiscountTypeDetail, new String[]{"FIXED", "PERCENT"});
     }
 
+    /**
+     * Configures a date picker for an EditText field.
+     */
     private void setupDatePicker(android.widget.EditText editText, android.widget.EditText dependOn, Runnable onDateSet) {
         editText.setFocusable(false);
         editText.setClickable(true);
@@ -91,6 +110,9 @@ public class CouponDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Loads coupon details from the backend and populates the UI.
+     */
     private void loadCouponDetails() {
         binding.tvCouponId.setText(DateTimeUtils.formatId(couponId));
         binding.tvCouponId.setVisibility(View.VISIBLE);
@@ -111,6 +133,9 @@ public class CouponDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Validates input and saves the coupon record.
+     */
     private void saveCoupon() {
         if (!InputValidator.isNotEmpty(binding.etCouponCodeDetail, "Coupon Code")) return;
         if (!InputValidator.isGreaterThanZero(binding.etDiscountValueDetail, "Discount Value")) return;
@@ -156,6 +181,9 @@ public class CouponDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Displays a confirmation dialog before deleting the coupon.
+     */
     private void confirmDelete() {
         new AlertDialog.Builder(requireContext())
                 .setTitle("Delete Coupon")

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/CustomerDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single customer.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.os.Bundle;
@@ -21,6 +28,9 @@ import javax.inject.Inject;
 
 import dagger.hilt.android.AndroidEntryPoint;
 
+/**
+ * Fragment for displaying and editing customer details.
+ */
 @AndroidEntryPoint
 public class CustomerDetailFragment extends Fragment {
 
@@ -31,6 +41,9 @@ public class CustomerDetailFragment extends Fragment {
 
     private final String[] STATUSES = {"Active", "Inactive"};
 
+    /**
+     * Inflates the layout, initializes ViewModel, and sets up UI components.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -49,10 +62,16 @@ public class CustomerDetailFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Initializes the spinners with data.
+     */
     private void setupSpinners() {
         SpinnerUtils.setupStringSpinner(requireContext(), binding.spinnerCustomerStatus, STATUSES);
     }
 
+    /**
+     * Uses fragment arguments to determine if we are editing an existing record.
+     */
     private void handleArguments() {
         Bundle a = getArguments();
         if (a != null && a.getBoolean("isEditing", false)) {
@@ -86,6 +105,9 @@ public class CustomerDetailFragment extends Fragment {
         }
     }
 
+    /**
+     * Loads customer data from the backend.
+     */
     private void loadCustomerData(long id) {
         viewModel.loadCustomer(id).observe(getViewLifecycleOwner(), resource -> {
             if (resource != null) {
@@ -105,12 +127,18 @@ public class CustomerDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Shows or hides the loading bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null && binding.progressBar != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Validates input and saves the customer record.
+     */
     private void save() {
         if (!InputValidator.isNotEmpty(binding.etCustomerUsername, "Username")) return;
 
@@ -160,6 +188,9 @@ public class CustomerDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Displays a confirmation dialog before deleting the customer.
+     */
     private void confirmDelete() {
         DialogUtils.showDeleteConfirmDialog(requireContext(), "Customer", () ->
                 viewModel.deleteCustomer().observe(getViewLifecycleOwner(), resource -> {
@@ -175,10 +206,16 @@ public class CustomerDetailFragment extends Fragment {
                 }));
     }
 
+    /**
+     * Navigates back to the previous screen.
+     */
     private void navigateBack() {
         NavHostFragment.findNavController(this).popBackStack();
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/InventoryDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single inventory item.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.os.Bundle;
@@ -37,12 +44,18 @@ public class InventoryDetailFragment extends Fragment {
     private long preselectedStoreId = -1;
     private long preselectedProductId = -1;
 
+    /**
+     * Initializes the fragment and its ViewModel.
+     */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         viewModel = new ViewModelProvider(this).get(InventoryDetailViewModel.class);
     }
 
+    /**
+     * Inflates the layout for the fragment.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -50,6 +63,9 @@ public class InventoryDetailFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Sets up UI components, observers, and loads initial data after the view is created.
+     */
     @Override
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
@@ -63,23 +79,35 @@ public class InventoryDetailFragment extends Fragment {
         binding.btnDeleteInventory.setOnClickListener(v -> confirmDelete());
     }
 
+    /**
+     * Sets up observers for ViewModel to update the UI dynamically.
+     */
     private void observeViewModel() {
         viewModel.getStoreList().observe(getViewLifecycleOwner(), list -> refreshStoreSpinner());
         viewModel.getProductList().observe(getViewLifecycleOwner(), list -> refreshProductSpinner());
     }
 
+    /**
+     * Shows or hides the loading bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null && binding.progressBar != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Loads initial data for the store and product spinners.
+     */
     private void loadSpinnersData() {
         viewModel.loadStores().observe(getViewLifecycleOwner(), resource -> {
             if (resource == null) return;
@@ -97,18 +125,27 @@ public class InventoryDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Refreshes the store spinner with the current data.
+     */
     private void refreshStoreSpinner() {
         SpinnerUtils.populateSpinner(requireContext(), binding.spinnerInventoryStore, viewModel.getStoreList().getValue(),
                 DropdownDTO::getLabel, "-- Select Store --",
                 preselectedStoreId, DropdownDTO::getId);
     }
 
+    /**
+     * Refreshes the product spinner with the current data.
+     */
     private void refreshProductSpinner() {
         SpinnerUtils.populateSpinner(requireContext(), binding.spinnerInventoryProduct, viewModel.getProductList().getValue(),
                 DropdownDTO::getLabel, "-- Select Product --",
                 preselectedProductId, DropdownDTO::getId);
     }
 
+    /**
+     * Uses fragment arguments to determine if we are editing an existing record.
+     */
     private void handleArguments() {
         Bundle args = getArguments();
         if (args != null && args.containsKey("inventoryId")) {
@@ -131,6 +168,9 @@ public class InventoryDetailFragment extends Fragment {
         }
     }
 
+    /**
+     * Loads the inventory data from the backend.
+     */
     private void loadInventoryData() {
         viewModel.loadInventory().observe(getViewLifecycleOwner(), resource -> {
             if (resource == null) return;
@@ -149,6 +189,9 @@ public class InventoryDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Validates input and saves the inventory record.
+     */
     private void saveInventory() {
         if (!InputValidator.isSpinnerSelected(binding.spinnerInventoryStore, "Store")) return;
         if (!InputValidator.isSpinnerSelected(binding.spinnerInventoryProduct, "Product")) return;
@@ -176,10 +219,16 @@ public class InventoryDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Displays a confirmation dialog before deleting the inventory record.
+     */
     private void confirmDelete() {
         DialogUtils.showDeleteConfirmDialog(requireContext(), "Inventory Item", this::deleteInventory);
     }
 
+    /**
+     * Calls the ViewModel to delete the inventory record.
+     */
     private void deleteInventory() {
         setButtonsEnabled(false);
         viewModel.deleteInventory().observe(getViewLifecycleOwner(), resource -> {
@@ -197,10 +246,16 @@ public class InventoryDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Navigates back to the previous screen.
+     */
     private void navigateBack() {
         NavHostFragment.findNavController(this).popBackStack();
     }
 
+    /**
+     * Enables or disables the action buttons.
+     */
     private void setButtonsEnabled(boolean enabled) {
         UIUtils.setViewsEnabled(enabled, binding.btnSaveInventory, binding.btnDeleteInventory, binding.btnInventoryBack);
     }

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/PetDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single pet.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.net.Uri;

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/ProductDetailFragment.java

@@ -1,3 +1,10 @@
+/*
+ * Detail screen for viewing and editing a single product.
+ *
+ * Author: Alex, Nikitha
+ * Date: April 2026
+ */
+
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
 import android.net.Uri;
@@ -58,6 +65,9 @@ public class ProductDetailFragment extends Fragment {
     @Inject @Named("baseUrl") String baseUrl;
     @Inject TokenManager tokenManager;
 
+    /**
+     * Initializes the fragment, its ViewModel, and the ImagePickerHelper.
+     */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -88,6 +98,9 @@ public class ProductDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Inflates the layout for the fragment.
+     */
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -95,6 +108,9 @@ public class ProductDetailFragment extends Fragment {
         return binding.getRoot();
     }
 
+    /**
+     * Sets up UI components, observers, and handles arguments after the view is created.
+     */
     @Override
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
@@ -108,6 +124,9 @@ public class ProductDetailFragment extends Fragment {
         binding.ivProductImage.setOnClickListener(v -> imagePickerHelper.showImagePickerDialog("Select Product Image", hasImage));
     }
 
+    /**
+     * Sets up observers for the ViewModel and loads product categories.
+     */
     private void observeViewModel() {
         viewModel.getCategoryList().observe(getViewLifecycleOwner(), list -> updateCategorySpinner());
 
@@ -120,24 +139,36 @@ public class ProductDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Shows or hides the loading bar.
+     */
     private void setLoading(boolean loading) {
         if (binding != null && binding.progressBar != null) {
             binding.progressBar.setVisibility(loading ? View.VISIBLE : View.GONE);
         }
     }
 
+    /**
+     * Populates the category spinner with available categories.
+     */
     private void updateCategorySpinner() {
         SpinnerUtils.populateSpinner(requireContext(), binding.spinnerProductCategory, viewModel.getCategoryList().getValue(),
                 DropdownDTO::getLabel, "-- Select Category --",
                 preselectedCategoryId, DropdownDTO::getId);
     }
 
+    /**
+     * Cleans up the binding reference.
+     */
     @Override
     public void onDestroyView() {
         super.onDestroyView();
         binding = null;
     }
 
+    /**
+     * Uses fragment arguments to determine if we are editing an existing record.
+     */
     private void handleArguments() {
         Bundle a = getArguments();
         if (a != null && a.containsKey("prodId")) {
@@ -158,6 +189,9 @@ public class ProductDetailFragment extends Fragment {
         }
     }
 
+    /**
+     * Loads the product details from the backend.
+     */
     private void loadProductData() {
         viewModel.loadProduct().observe(getViewLifecycleOwner(), resource -> {
             if (resource == null) return;
@@ -175,6 +209,9 @@ public class ProductDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Loads the product image from the server.
+     */
     private void loadProductImage() {
         String imageUrl = baseUrl + String.format(Locale.US, ProductApi.PRODUCT_IMAGE_PATH, viewModel.getProdId());
         String token = tokenManager.getToken();
@@ -192,6 +229,9 @@ public class ProductDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Performs image-related actions (removal or upload) after a successful product save.
+     */
     private void performPendingImageActions(String successMsg) {
         if (isImageRemoved) {
             viewModel.deleteProductImage().observe(getViewLifecycleOwner(), resource -> {
@@ -214,6 +254,9 @@ public class ProductDetailFragment extends Fragment {
         }
     }
 
+    /**
+     * Uploads the selected product image to the server.
+     */
     private void uploadProductImageAndNavigate(Uri uri, String successMsg) {
         File file = FileUtils.getFileFromUri(requireContext(), uri);
         if (file == null) {
@@ -239,6 +282,9 @@ public class ProductDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Validates input and saves the product record.
+     */
     private void saveProduct() {
         if (!InputValidator.isNotEmpty(binding.etProductName, "Product Name")) return;
         if (!InputValidator.isSpinnerSelected(binding.spinnerProductCategory, "Category")) return;
@@ -267,6 +313,9 @@ public class ProductDetailFragment extends Fragment {
         });
     }
 
+    /**
+     * Displays a confirmation dialog before deleting the product.
+     */
     private void confirmDelete() {
         DialogUtils.showDeleteConfirmDialog(requireContext(), "Product", () ->
                 viewModel.deleteProduct().observe(getViewLifecycleOwner(), resource -> {
@@ -280,6 +329,9 @@ public class ProductDetailFragment extends Fragment {
                 }));
     }
 
+    /**
+     * Navigates back to the previous screen.
+     */
     private void navigateBack() {
         NavHostFragment.findNavController(this).popBackStack();
     }