from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session

from app.database.connection import get_db
from app.schemas.auth import UserCreate, UserLogin, UserResponse, TokenResponse
from app.services.auth_service import AuthService
from app.middleware.auth import get_current_user
from app.database.models import User
from app.utils.validators import validate_email, validate_password

router = APIRouter(prefix="/api", tags=["auth"])


@router.post("/signup", response_model=TokenResponse, status_code=status.HTTP_201_CREATED)
async def signup(user_data: UserCreate, db: Session = Depends(get_db)):
    """
    Create a new user account.
    
    Args:
        user_data: User registration data
        db: Database session
        
    Returns:
        Access and refresh tokens with user info
        
    Raises:
        HTTPException: If email is invalid or already registered
    """
    print(f"[SIGNUP] Received signup request for email: {user_data.email}")
    
    # Validate email
    if not validate_email(user_data.email):
        print(f"[SIGNUP] Invalid email format: {user_data.email}")
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Invalid email format"
        )
    
    # Validate password
    is_valid, error_msg = validate_password(user_data.password)
    if not is_valid:
        print(f"[SIGNUP] Password validation failed: {error_msg}")
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=error_msg
        )
    
    try:
        # Create user
        print(f"[SIGNUP] Creating user...")
        user = AuthService.create_user(
            db=db,
            email=user_data.email,
            password=user_data.password,
            name=user_data.name
        )
        
        print(f"[SIGNUP] User created successfully: {user.id}")
        
        # Generate tokens
        tokens = AuthService.generate_tokens(user)
        
        print(f"[SIGNUP] Tokens generated successfully")
        
        return TokenResponse(
            access_token=tokens["access_token"],
            refresh_token=tokens["refresh_token"],
            user=UserResponse.from_orm(user)
        )
        
    except ValueError as e:
        print(f"[SIGNUP] ValueError: {str(e)}")
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e)
        )
    except Exception as e:
        print(f"[SIGNUP] Unexpected error: {type(e).__name__}: {str(e)}")
        import traceback
        traceback.print_exc()
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="An error occurred during signup"
        )


@router.post("/login", response_model=TokenResponse)
async def login(credentials: UserLogin, db: Session = Depends(get_db)):
    """
    Authenticate user and return tokens.
    
    Args:
        credentials: User login credentials
        db: Database session
        
    Returns:
        Access and refresh tokens with user info
        
    Raises:
        HTTPException: If credentials are invalid
    """
    # Authenticate user
    user = AuthService.authenticate_user(
        db=db,
        email=credentials.email,
        password=credentials.password
    )
    
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Incorrect email or password"
        )
    
    # Generate tokens
    tokens = AuthService.generate_tokens(user)
    
    return TokenResponse(
        access_token=tokens["access_token"],
        refresh_token=tokens["refresh_token"],
        user=UserResponse.from_orm(user)
    )


@router.get("/check-auth", response_model=UserResponse)
async def check_auth(current_user: User = Depends(get_current_user)):
    """
    Verify authentication token and return user info.
    
    Args:
        current_user: Current authenticated user
        
    Returns:
        User information
        
    Raises:
        HTTPException: If token is invalid or expired
    """
    return UserResponse.from_orm(current_user)


@router.post("/auth/google", response_model=TokenResponse)
async def google_auth(
    request: dict,
    db: Session = Depends(get_db)
):
    """
    Authenticate user with Google OAuth and return JWT tokens.
    
    Args:
        request: Dictionary with 'credential' field (Google JWT token)
        db: Database session
        
    Returns:
        Access and refresh JWT tokens with user info
        
    Raises:
        HTTPException: If Google token is invalid
    """
    from app.config.settings import settings
    
    print(f"[GOOGLE AUTH] Received Google OAuth request")
    
    try:
        credential = request.get("credential")
        if not credential:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail="Google credential is required"
            )
        
        print(f"[GOOGLE AUTH] Verifying Google token...")
        
        # Verify Google token and get user info
        google_data = await AuthService.verify_google_token(
            credential=credential,
            client_id=settings.GOOGLE_CLIENT_ID
        )
        
        print(f"[GOOGLE AUTH] Token verified for email: {google_data['email']}")
        
        # Create or get user
        user = AuthService.create_user_from_google(
            db=db,
            google_id=google_data["google_id"],
            email=google_data["email"],
            name=google_data.get("name")
        )
        
        print(f"[GOOGLE AUTH] User created/retrieved: {user.id}")
        
        # Generate JWT tokens (same as email/password login)
        tokens = AuthService.generate_tokens(user)
        
        print(f"[GOOGLE AUTH] JWT tokens generated successfully")
        
        return TokenResponse(
            access_token=tokens["access_token"],
            refresh_token=tokens["refresh_token"],
            user=UserResponse.from_orm(user)
        )
        
    except ValueError as e:
        print(f"[GOOGLE AUTH] ValueError: {str(e)}")
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e)
        )
    except Exception as e:
        print(f"[GOOGLE AUTH] Unexpected error: {type(e).__name__}: {str(e)}")
        import traceback
        traceback.print_exc()
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Failed to authenticate with Google"
        )