A modern, offline-first Android chat application built entirely with Jetpack Compose. This project demonstrates a robust, scalable architecture and a feature-set designed for a seamless user experience.

• Real-Time Communication: Leverages Firebase Cloud Firestore to deliver instant messaging with real-time updates.
• Offline-First Architecture: Caches data using the Room persistence library, ensuring seamless access and message queueing even without a network connection. Data syncs automatically upon reconnection.
• Multimedia Messaging: Utilizes Firebase Cloud Storage for efficient image sharing and retrieval.

• Declarative UI: The entire UI is built with Jetpack Compose, enabling a reactive, state-driven user interface that is more concise and powerful than the traditional XML-based approach.
• Single Source of Truth (SSoT): The repository pattern ensures that all application data flows from a single, reliable source (the Room database), which is synchronized with the network. This provides data consistency and a seamless offline experience.
• State Management: Leverages ViewModels and Kotlin's StateFlow to manage and expose UI state, ensuring that the UI is always a reflection of the underlying application data in a lifecycle-aware manner.
• Dependency Injection: Uses Koin for dependency inversion, decoupling components and making them easier to manage, replace, and test.

This project utilizes a curated selection of modern libraries and tools to deliver a high-quality product.

• Core:

  • Kotlin: Official language for Android development.
  • Coroutines & Flow: For asynchronous and reactive programming.

• UI:

  • Jetpack Compose: Modern toolkit for building native Android UI.
  • Material 3: The latest version of Google's open-source design system.

• Architecture & DI:

  • Jetpack ViewModel: Manages UI-related data in a lifecycle-conscious way.
  • Koin: A pragmatic and lightweight dependency injection framework.

• Data & Networking:

  • Room: Persistence library for robust offline data caching.
  • Firebase Suite:
    • Authentication: For secure user sign-in and identity management.
    • Cloud Firestore: For real-time, persistent data synchronization.
    • Cloud Storage: For storing and serving user-generated content like images.

1. Create a new project in your Firebase Console.
2. Generate a SHA-1 debug key by running ./gradlew signingReport in the Android Studio terminal and add it to your Firebase project settings.
3. Download the google-services.json file from your Firebase project console.
4. Switch to Project view in Android Studio and place the google-services.json file in the app/ directory.
5. Build and run the application.

The following features are planned for future development to further enhance the application's capabilities:

• Presence System: Implement user status indicators (Online, Typing, Last Seen).
• Voice Messaging: Add support for sending and receiving voice notes.
• Expanded Media Support: Allow sharing of additional media types like videos and documents.
• Group Chat Functionality: Develop features for multi-user conversations.
• Contact Integration: Introduce the ability to invite users from the device's contacts.
• WebRTC Integration: Implement audio and video calling features.

Contributions are welcome! Please feel free to submit a pull request. This project would particularly benefit from contributions in the area of unit and instrumentation testing to increase code coverage and robustness.