TermCall

A CLI-based video/audio calling app for the terminal using WebRTC and Firebase.

Features

• Peer-to-peer video and audio calls in your terminal
• Remote video as colored ASCII art
• Local video preview as Sixel graphics (Sixel-compatible terminal required)
• Simple CLI interface for browsing users and making calls

Requirements

• Python 3.8+
• A Sixel-compatible terminal (e.g., xterm -ti vt340, mlterm) for local video preview
• Webcam and microphone

Installation

1. Install TermCall (after building the package):

   pip install termcall
   

2. Install system dependencies (if needed):

   • macOS: brew install libjpeg
   • Ubuntu: sudo apt-get install libopencv-dev

Usage

After installation, run:

termcall

• On first run, you will be prompted for your email and full name.
• Browse users, initiate calls, and accept/decline incoming calls from the CLI menu.
• During a call:
  • Remote video is shown as ASCII art
  • Local video preview (bottom right) uses Sixel graphics (if supported)
  • Controls: m to mute audio, v to mute video, q to quit call

Database & Security

• TermCall connects to the public TermCall Firebase database automatically. You do NOT need to set up your own Firebase or provide any credentials.

Firebase Database Rules:

{
  "rules": {
    "users": {
      "$email": {
        // Anyone can read user profiles
        ".read": true,
        // Only allow writes if the provided token matches the stored token
        ".write": "(!data.exists() && newData.child('token').val() != null) || (data.child('token').val() === newData.child('token').val())"
      }
    },
    "call_requests": {
      "$request_id": {
        // Anyone can read call requests
        ".read": true,
        // Only allow the caller or callee (with correct token) to write/update/delete
        ".write": "(!data.exists() && newData.child('caller_email').val() != null && newData.child('callee_email').val() != null && newData.child('token').val() != null) || (data.child('token').val() === newData.child('token').val())"
      }
    },
    "signaling": {
      "$call_id": {
        "$peer_email": {
          // Anyone can read signaling data
          ".read": true,
          // Only allow the peer (with correct token) to write/update/delete
          ".write": "(!data.exists() && newData.child('token').val() != null) || (data.child('token').val() === newData.child('token').val())"
        }
      }
    }
  }
}

• TermCall uses a central Firebase Realtime Database, maintained by the project owner.
• The app connects via the public database URL using the Firebase REST API.
• No admin credentials or serviceAccountKey.json are distributed.
• Users do NOT need to set up their own Firebase project or credentials.

Future Improvements

• Add authentication (e.g., anonymous or email/password) to restrict users to their own data

• Update database rules to enforce per-user access

• Modularize codebase for maintainability

• Improve packaging and distribution (PyPI, Homebrew, etc.)

• Monitor and mitigate abuse/spam

• Migrate to Firebase Authentication (Long-Term):

  • Implement Firebase Authentication (email/password, anonymous, etc.) for all users.
  • Use auth.uid in database rules to enforce per-user access and secure all sensitive operations.
  • This enables robust, scalable security and is recommended for production deployments.

Distribution & Packaging

• See Distribution.md for historical notes and advanced packaging options
• The main user experience is via pip install and the termcall CLI

License

MIT License