Fixes ICE candidate issue

[martian56]

This pull request introduces several improvements and bug fixes to both the backend and frontend of the application, with a focus on configuration flexibility, WebRTC connection handling, and enhanced debugging. The main changes include improved environment variable management in the backend, more robust and debuggable WebRTC peer connection logic, and safer, more maintainable WebSocket handling in the frontend.

Backend Configuration Improvements:

• Enhanced the Settings class in backend/config.py to use Pydantic's SettingsConfigDict for better environment variable management, including ignoring extra variables and supporting case insensitivity. Also added properties to handle CORS origins as both a string and a list, and updated the default application name. [1] [2]

WebRTC Debugging and Robustness:

• Added detailed logging throughout the WebRTC connection process in frontend/src/hooks/useWebRTC.ts and frontend/src/pages/MeetingRoom.tsx, including when adding tracks, creating/reusing peer connections, and handling offers/answers/ICE candidates. Improved logic to avoid duplicate peer connections and offers, and added error handling for signaling state issues. [1] [2] [3] [4] [5] [6]

WebSocket Hook Enhancements:

• Refactored the useWebSocket hook to use a ref for the onMessage callback, preventing unnecessary reconnections and stale closures. This makes the hook safer and easier to maintain. [1] [2] [3]

[Copilot]

Pull Request Overview

This PR enhances the WebRTC peer-to-peer connection reliability by improving connection initialization flow, adding comprehensive error handling, and updating the backend configuration to use Pydantic v2 patterns.

• Refactored WebRTC connection establishment to prevent duplicate peer connections and race conditions
• Added extensive logging throughout the WebSocket and WebRTC message flow for better debugging
• Migrated backend configuration to Pydantic v2 with SettingsConfigDict

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
frontend/src/pages/MeetingRoom.tsx	Enhanced WebSocket message handling with additional logging, duplicate connection checks, error handling for async operations, and a default case for unhandled message types
frontend/src/hooks/useWebSocket.ts	Fixed dependency issues by using useRef pattern for the onMessage callback to prevent unnecessary WebSocket reconnections
frontend/src/hooks/useWebRTC.ts	Improved offer handling to reuse existing peer connections, added signaling state validation, and comprehensive logging throughout the connection lifecycle
backend/config.py	Updated to Pydantic v2 with SettingsConfigDict, converted CORS origins to property methods, and changed app_name from "VideoCall" to "LinkUp"

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[Copilot]

The comment suggests CORS_ORIGINS is an extra environment variable to be ignored, but it's actually being used by the cors_origins_str property method via os.getenv(). This comment is misleading since CORS_ORIGINS is a required configuration, not an extra variable to ignore.

Suggested change

	extra="ignore" # Ignore extra environment variables like CORS_ORIGINS
	extra="ignore" # Ignore extra environment variables not defined in the model

[Copilot]

Excessive debug logging has been added throughout the WebRTC connection flow. While useful for development, this amount of console logging in production code can:

1. Impact performance with frequent console operations
2. Clutter production logs making it harder to find actual issues
3. Potentially expose sensitive connection details in production logs

Consider either:

• Using a proper logging library with configurable log levels
• Wrapping these logs in a debug flag check
• Removing non-critical logs before production deployment

[Copilot]

The empty if block when pc.signalingState === 'stable' serves no purpose and reduces code clarity. If the condition is meant to allow fall-through to the try block below, consider removing the empty branch and inverting the logic:

if (pc.remoteDescription && pc.signalingState !== 'stable') {
  console.error('Cannot set remote description, signaling state:', pc.signalingState);
  return null;
}

This makes the intent clearer and eliminates the confusing empty block.