💬 ChatApplication

A simple Qt-based TCP chat application that includes:

• ChatServer: Handles multiple client connections, manages usernames, and routes messages.
• ChatClient: GUI chat interface with username support, dark mode, emoji picker, and online user list.

This project is built using Qt (Widgets + Network module) and demonstrates real-time messaging using QTcpSocket and QTcpServer.

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📁 Repository Structure

ChatApplication/
├── ChatClient/    # Qt GUI client
└── ChatServer/    # Qt server console app

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🚀 Features

ChatClient

• Username support (saved using QSettings)
• Dark mode toggle
• Emoji picker using QInputDialog
• Chat saving to .txt files
• Clear chat history
• Online user list
• Handles /nick, /users, /save, and /clear commands

ChatServer

• Accepts multiple TCP clients
• Tracks usernames using QHash
• Validates uniqueness of usernames
• Handles:
  • /nick <new_name> — Change nickname
  • /users — View online users
• Broadcasts join/leave/nickname changes to all clients

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💡 Supported Commands

Inside the client, type:

/nick <new_username>     # Change your nickname
/users                   # List online users
/clear                   # Clear the chat box
/save                    # Save chat history to a file

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🛠️ Requirements

• Qt 5 or Qt 6 (QtCore, QtWidgets, QtNetwork modules)
• C++17 or later
• Tested with Qt Creator and qmake

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🧑‍💻 Build Instructions

1. Clone the repository

git clone https://github.com/your-username/ChatApplication.git
cd ChatApplication

2. Build the Server

cd ChatServer
qmake
make   # or mingw32-make on Windows
./ChatServer

3. Build the Client

cd ../ChatClient
qmake
make
./ChatClient

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🧪 How It Works

• Server listens on 127.0.0.1:1234
• Clients connect, send a username first
• Server maps sockets to usernames and routes incoming messages
• Server sends system messages like:
  • *** Paul joined the chat ***
  • *** Paul is now John ***
  • *** John left the chat ***

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📝 Notes

• If username is not provided, client uses one of the following:
  • Saved name from last session
  • Prompted via QInputDialog
  • Fallback: Guest_<timestamp> if all else fails
• Data is stored using QSettings, so preferences persist after restart.

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📄 License

MIT License © 2025 Paul Gaikwad

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🙌 Acknowledgements

This project was developed to demonstrate a real-time networked Qt application with modern C++ and Qt Widgets.