🔥 FireChat - Real-Time Chat App

A modern Android chat application built with Jetpack Compose, Firebase, and Koin dependency injection, featuring real-time messaging and a sleek Material Design 3 UI.

✨ Features

• Real-time messaging with Firebase Firestore
• User authentication with Firebase Auth
• Material Design 3 UI with dark/light theme support
• Clean Architecture with MVVM pattern
• Dependency Injection using Koin
• User presence indicators (online/offline status)
• Message status indicators (sent/delivered/read)
• Empty state handling for better UX
• Avatar support with initials fallback

📱 Screenshots

The app includes the following screens matching the provided UI design:

• Chat List - Shows all conversations with last message and time
• Empty Chat List - Placeholder when no conversations exist
• Chat Screen - Real-time messaging with message bubbles
• Empty Chat - Initial state for new conversations
• Login/Register - Firebase authentication screens

🛠 Tech Stack

Core

• Kotlin - Programming language
• Jetpack Compose - Modern UI toolkit
• Material Design 3 - Design system

Architecture

• MVVM - Architectural pattern
• Clean Architecture - Separation of concerns
• Use Cases - Business logic encapsulation
• Repository Pattern - Data abstraction

Dependencies

• Firebase Auth - User authentication
• Firebase Firestore - Real-time database
• Firebase Storage - File uploads
• Koin - Dependency injection
• Navigation Compose - App navigation
• Coil - Image loading
• Room - Local caching (ready for implementation)

🚀 Getting Started

Prerequisites

• Android Studio Arctic Fox or newer
• Android SDK 23+
• Google account for Firebase setup

Firebase Setup

1. Create Firebase Project

   1. Go to Firebase Console (https://console.firebase.google.com/)
   2. Create a new project called "FireChat" or your preferred name
   3. Enable Google Analytics (optional)
   

2. Add Android App

   1. Click "Add app" → Android
   2. Package name: com.example.firechat
   3. App nickname: FireChat (optional)
   4. SHA-1: Generate using: ./gradlew signingReport
   

3. Download Configuration

   1. Download google-services.json
   2. Place it in app/ directory (replace the placeholder file)
   

4. Enable Firebase Services

   Authentication:
   1. Go to Authentication → Sign-in method
   2. Enable Email/Password authentication
   
   Firestore:
   1. Go to Firestore Database → Create database
   2. Choose "Start in test mode" 
   3. Select a location close to your users
   4. Go to Rules tab
   5. For testing: Use firestore-test.rules (more permissive)
   6. For production: Use firestore.rules (secure)
   7. Click "Publish"
   
   Optional - For better performance with large datasets:
   7. Go to Indexes tab
   8. Import firestore.indexes.json or create indexes manually if needed
   

Installation

1. Clone the repository

   git clone <your-repo-url>
   cd FireChat

2. Open in Android Studio

   1. Open Android Studio
   2. File → Open → Select the FireChat folder
   3. Wait for Gradle sync to complete
   

3. Replace Firebase Configuration

   Replace google-services.json with your actual Firebase config file
   

4. Build and Run

   ./gradlew assembleDebug

   Or use Android Studio's Run button

📂 Project Structure

app/src/main/java/com/example/firechat/
├── data/
│   ├── model/              # Data models (User, Chat, Message)
│   └── repository/         # Repository implementations
├── domain/
│   ├── repository/         # Repository interfaces
│   └── usecase/           # Business logic use cases
├── di/                    # Dependency injection modules
├── presentation/
│   ├── screen/            # Compose UI screens
│   └── viewmodel/         # ViewModels
├── navigation/            # Navigation setup
├── ui/theme/             # Material Design theme
├── FireChatApplication.kt # Application class
└── MainActivity.kt       # Main activity

🏗 Architecture

The app follows Clean Architecture principles:

Data Layer

• Models: User, Chat, Message data classes
• Repositories: Firebase implementation for data operations
• Remote Data Source: Firebase Auth & Firestore

Domain Layer

• Use Cases: Business logic (Login, SendMessage, GetChats, etc.)
• Repository Interfaces: Abstraction for data operations

Presentation Layer

• ViewModels: UI state management with StateFlow
• Compose Screens: UI components and screens
• Navigation: Navigation between screens

🔥 Firebase Collections Structure

/users/{userId}
├── id: String
├── email: String
├── displayName: String
├── avatarUrl: String
├── isOnline: Boolean
└── lastSeen: Long

/chats/{chatId}
├── participants: Array<String>
├── lastMessage: String
├── lastMessageType: String
├── lastMessageTime: Long
├── lastMessageSender: String
└── /messages/{messageId}
    ├── senderId: String
    ├── receiverId: String
    ├── content: String
    ├── type: String
    ├── timestamp: Long
    ├── status: String
    ├── senderName: String
    └── senderAvatar: String

🎨 UI Design

The app matches the provided UI design with:

• Chat List: User avatars, last messages, timestamps, unread badges
• Chat Screen: Message bubbles, status indicators, input bar
• Empty States: Friendly messages for empty conversations
• Material 3: Modern design with proper theming

🔧 Configuration

Koin Modules

All dependencies are configured in AppModule.kt:

• Firebase instances
• Repositories
• Use Cases
• ViewModels

Theme

Material Design 3 theme configured in ui/theme/ with:

• Color schemes (light/dark)
• Typography
• Shapes

🧪 Testing

The project is set up for testing with:

• Unit Tests: Business logic testing
• UI Tests: Compose UI testing
• Integration Tests: Firebase integration testing

Run tests:

./gradlew test
./gradlew connectedAndroidTest

📱 APK Build

To build a release APK:

1. Generate signed APK

   ./gradlew assembleRelease

2. Location: app/build/outputs/apk/release/app-release.apk

🤝 Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

🙏 Acknowledgments

• Firebase - Backend as a Service
• Jetpack Compose - Modern Android UI
• Material Design - Design system
• Koin - Dependency injection framework

---

Built with ❤️ for modern Android development# FireChat