Oauth - Google Login Screen Integration

[coderabbitai]

Problem

The login screen does not expose a Google login button or complete the token exchange with the backend.

Scope

• Add Google button to login screen.
• On authorize(), call OAuthService.signInWithOAuth with provider GOOGLE.

Approach

• Inject OAuthService in the screen; on success, navigate to the app home.

Dependencies

• Blocked By:
• Blocks:

Files to Modify/Create

• talawa/lib/views/auth/login_screen.dart
• talawa/lib/widgets/oauth/oauth_login_section.dart

Acceptance Criteria

• All existing functionality must be maintained
• Implementation must ensure no breaking changes when PR is merged

Testing Requirements

• All tests must pass successfully
• Code coverage must be >= 96%

Sample Code

This sample code is only representative of what could be done. It is provided only to give a general outline. You will need to use your initiative and industry best practices to find a solution that is suitable for the application.

// talawa/lib/views/auth/login_screen.dart (snippet)
onGooglePressed: () async {
  final code = await googleProvider.authorize();
  if (code == null) return;
  await oauthService.signInWithOAuth(
    provider: "GOOGLE", authorizationCode: code, redirectUri: "talawa://oauth/callback");
},