from typing import Optional, Dict, Any
import jwt
from datetime import datetime, timedelta

class AuthService:
    def __init__(self, auth_config: Dict[str, Any]):
        self.config = auth_config
        self._current_user = None
        self._auth_token = None
        
    def is_authenticated(self) -> bool:
        """Check if user is authenticated"""
        return self._auth_token is not None and self._current_user is not None
    
    def get_current_user(self) -> Optional[Dict[str, Any]]:
        """Get current authenticated user"""
        return self._current_user
    
    def get_auth_token(self) -> Optional[str]:
        """Get current auth token"""
        return self._auth_token
    
    def login(self, username: str, password: str) -> bool:
        """Simple login (in production, this would integrate with external provider)"""
        # For demo purposes, simple validation
        if username == "admin" and password == "admin":
            # Generate a simple JWT token
            payload = {
                "user_id": "admin",
                "username": username,
                "role": "admin",
                "exp": datetime.utcnow() + timedelta(hours=8)
            }
            self._auth_token = jwt.encode(payload, self.config['secret_key'], algorithm="HS256")
            self._current_user = {
                "user_id": "admin",
                "username": username,
                "role": "admin"
            }
            return True
        return False
    
    def logout(self):
        """Logout current user"""
        self._current_user = None
        self._auth_token = None
    
    def validate_token(self, token: str) -> bool:
        """Validate JWT token"""
        try:
            payload = jwt.decode(token, self.config['secret_key'], algorithms=["HS256"])
            self._current_user = {
                "user_id": payload["user_id"],
                "username": payload["username"],
                "role": payload["role"]
            }
            self._auth_token = token
            return True
        except jwt.InvalidTokenError:
            return False