CppGameChat

A modular, production-style C++/Qt5 desktop chat application demonstrating real-time friends, chat, and rich presence using Google Cloud Firestore for storage.

Demo Video

Demo.mp4

Screenshots

Features

• Clean Qt5 Widgets UI: Login screen -> Chat interface with friends list
• Real-time Chat: Global chat room with live message updates via polling
• Friends & Presence: Static friend list with online/offline status indicators
• Firestore Integration: Uses Firestore REST API (no Firebase Auth required)
• Modular Architecture: Clean separation with services, models, and UI layers

Prerequisites

• Qt5: Qt5 with Widgets and Network modules
• CMake: Version 3.16 or later
• C++17: Compatible compiler
• GoogleTest: For running unit tests (optional)
• Google Cloud Firestore: Project with API key

Building

1. Install CMake:

   # macOS with Homebrew
   brew install cmake
   
   # Ubuntu/Debian
   sudo apt-get install cmake
   
   # CentOS/RHEL/Fedora
   sudo dnf install cmake
   # or: sudo yum install cmake
   
   # Windows
   # Download from https://cmake.org/download/
   # Or via Chocolatey: choco install cmake
   # Or via Scoop: scoop install cmake

2. Install Qt5:

   # macOS with Homebrew
   brew install qt@5
   
   # Ubuntu/Debian
   sudo apt-get install qtbase5-dev qtbase5-dev-tools libqt5network5-dev
   
   # Windows
   # Download Qt5 from https://www.qt.io/download

3. Clone and build:

   git clone <repository-url>
   cd CppGameChat
   mkdir build && cd build
   cmake ..
   make

4. Create configuration file in the build directory (config.json):

   {
     "apiKey": "your-firestore-api-key",
     "projectId": "your-firestore-project-id",
     "databaseId": "(default)",
     "pollIntervalMs": 1200,
     "presenceHeartbeatMs": 5000,
     "presenceStaleMs": 12000
   }

5. Run the application:

   ./app/QtChatPresence

Firestore Setup

Using Firestore Emulator (Recommended for Development)

1. Install Firebase Tools:

   npm install -g firebase-tools

2. Start emulator:

   firebase emulators:start --only firestore

3. Update config.json to point to emulator:

   • Use project ID: demo-project
   • The emulator runs on localhost:8080 by default

Using Cloud Firestore

1. Create a Firebase project at https://console.firebase.google.com
2. Enable Firestore Database
3. Get your API key from Project Settings (Web)
4. Use permissive rules for demo.

Data Structure

The application uses these Firestore collections:

• presence/{userId}: User online/offline status and heartbeats
• rooms/global/messages/{messageId}: Chat messages in the global room

Testing

Run unit tests with GoogleTest:

cd build
make
./tests/core_tests/core_tests

Tests cover:

• Presence calculation logic
• Retry policy with exponential backoff
• Firestore JSON mapping and parsing

Friend List

The app includes 5 demo friends:

• Jon
• Arya
• Tyrion
• Daenerys
• Sansa

Their online/offline status is determined by looking up their presence in Firestore.

Troubleshooting

Build Issues:

• Make sure Qt5 is in your PATH
• Check CMake can find Qt5: cmake .. -DQt5_DIR=/path/to/qt5

Connection Issues:

• Verify your config.json has valid apiKey and projectId
• Check Firestore security rules allow read/write
• For emulator: ensure it's running on localhost:8080

No Messages Appearing:

• Verify your API key has Firestore permissions
• Try sending a message through Firestore console directly