import os
from typing import Dict, Optional
from authlib.integrations.flask_client import OAuth
from .base import OAuthProvider
from .google import GoogleOAuthProvider
from .github import GitHubOAuthProvider


class OAuthProviderRegistry:
    """Registry for OAuth providers."""
    
    def __init__(self, oauth: OAuth):
        self.oauth = oauth
        self._providers: Dict[str, OAuthProvider] = {}
        self._initialize_providers()
        
    def _initialize_providers(self):
        """Initialize available providers based on environment variables."""
        # Google OAuth
        google_client_id = os.getenv('GOOGLE_CLIENT_ID')
        google_client_secret = os.getenv('GOOGLE_CLIENT_SECRET')
        if google_client_id and google_client_secret:
            self._providers['google'] = GoogleOAuthProvider(
                self.oauth, google_client_id, google_client_secret
            )
            
        # GitHub OAuth
        github_client_id = os.getenv('GITHUB_CLIENT_ID')
        github_client_secret = os.getenv('GITHUB_CLIENT_SECRET')
        if github_client_id and github_client_secret:
            self._providers['github'] = GitHubOAuthProvider(
                self.oauth, github_client_id, github_client_secret
            )
            
    def get_provider(self, name: str) -> Optional[OAuthProvider]:
        """Get OAuth provider by name."""
        return self._providers.get(name)
        
    def get_available_providers(self) -> Dict[str, OAuthProvider]:
        """Get all available providers."""
        return self._providers.copy()
        
    def is_provider_available(self, name: str) -> bool:
        """Check if provider is available."""
        return name in self._providers