"""Authentication endpoints."""

import secrets
import time
from typing import Annotated, Any

from fastapi import APIRouter, Cookie, Depends, HTTPException, Query, Response, status
from fastapi.responses import RedirectResponse

from app.core.config import settings
from app.core.dependencies import (
    get_auth_service,
    get_current_active_user,
    get_current_active_user_flexible,
    get_oauth_service,
)
from app.core.logging import get_logger
from app.models.user import User
from app.schemas.auth import (
    ApiTokenRequest,
    ApiTokenResponse,
    ApiTokenStatusResponse,
    UserLoginRequest,
    UserRegisterRequest,
    UserResponse,
)
from app.services.auth import AuthService
from app.services.oauth import OAuthService
from app.utils.auth import JWTUtils, TokenUtils
from app.utils.cookies import set_access_token_cookie, set_auth_cookies

router = APIRouter(prefix="/auth", tags=["authentication"])
logger = get_logger(__name__)

# Global temporary storage for OAuth codes (in production, use Redis with TTL)
_temp_oauth_codes: dict[str, dict[str, Any]] = {}


# Authentication endpoints
@router.post(
    "/register",
    status_code=status.HTTP_201_CREATED,
)
async def register(
    request: UserRegisterRequest,
    response: Response,
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
) -> UserResponse:
    """Register a new user account."""
    try:
        auth_response = await auth_service.register(request)

        # Create and store refresh token - need to get User object from service
        user = await auth_service.get_current_user(auth_response.user.id)
        refresh_token = await auth_service.create_and_store_refresh_token(user)

        # Set HTTP-only cookies for both tokens
        set_auth_cookies(
            response=response,
            access_token=auth_response.token.access_token,
            refresh_token=refresh_token,
            expires_in=auth_response.token.expires_in,
        )

    except HTTPException:
        raise
    except Exception as e:
        logger.exception("Registration failed for email: %s", request.email)
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Registration failed",
        ) from e
    else:
        return auth_response.user


@router.post("/login")
async def login(
    request: UserLoginRequest,
    response: Response,
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
) -> UserResponse:
    """Authenticate a user and return access token."""
    try:
        auth_response = await auth_service.login(request)

        # Create and store refresh token - need to get User object from service
        user = await auth_service.get_current_user(auth_response.user.id)
        refresh_token = await auth_service.create_and_store_refresh_token(user)

        # Set HTTP-only cookies for both tokens
        set_auth_cookies(
            response=response,
            access_token=auth_response.token.access_token,
            refresh_token=refresh_token,
            expires_in=auth_response.token.expires_in,
        )

    except HTTPException:
        raise
    except Exception as e:
        logger.exception("Login failed for email: %s", request.email)
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Login failed",
        ) from e
    else:
        return auth_response.user


@router.get("/me")
async def get_current_user_info(
    current_user: Annotated[User, Depends(get_current_active_user_flexible)],
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
) -> UserResponse:
    """Get current user information."""
    try:
        return await auth_service.create_user_response(current_user)
    except Exception as e:
        logger.exception("Failed to get current user info")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Failed to retrieve user information",
        ) from e


@router.post("/refresh")
async def refresh_token(
    response: Response,
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
    refresh_token: Annotated[str | None, Cookie()] = None,
) -> dict[str, str]:
    """Refresh access token using refresh token."""
    try:
        if not refresh_token:
            raise HTTPException(
                status_code=status.HTTP_401_UNAUTHORIZED,
                detail="No refresh token provided",
            )

        # Get new access token
        token_response = await auth_service.refresh_access_token(refresh_token)

        # Set new access token cookie
        set_access_token_cookie(
            response=response,
            access_token=token_response.access_token,
            expires_in=token_response.expires_in,
        )

    except HTTPException:
        raise
    except Exception as e:
        logger.exception("Token refresh failed")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Token refresh failed",
        ) from e
    else:
        return {"message": "Token refreshed successfully"}


@router.post("/logout")
async def logout(
    response: Response,
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
    access_token: Annotated[str | None, Cookie()] = None,
    refresh_token: Annotated[str | None, Cookie()] = None,
) -> dict[str, str]:
    """Logout endpoint - clears cookies and revokes refresh token."""
    user = None

    # Try to get user from access token first
    if access_token:
        try:
            payload = JWTUtils.decode_access_token(access_token)
            user_id_str = payload.get("sub")
            if user_id_str:
                user_id = int(user_id_str)
                user = await auth_service.get_current_user(user_id)
                logger.info("Found user from access token: %s", user.email)
        except (HTTPException, Exception) as e:
            logger.info("Access token validation failed: %s", str(e))

    # If no user found, try refresh token
    if not user and refresh_token:
        try:
            payload = JWTUtils.decode_refresh_token(refresh_token)
            user_id_str = payload.get("sub")
            if user_id_str:
                user_id = int(user_id_str)
                user = await auth_service.get_current_user(user_id)
                logger.info("Found user from refresh token: %s", user.email)
        except (HTTPException, Exception) as e:
            logger.info("Refresh token validation failed: %s", str(e))

    # If we found a user, revoke their refresh token
    if user:
        await auth_service.revoke_refresh_token(user)
        logger.info("Successfully revoked refresh token for user: %s", user.email)
    else:
        logger.info("No user found, skipping token revocation")

    # Always clear both cookies regardless of token validity
    response.delete_cookie(
        key="access_token",
        httponly=True,
        secure=settings.COOKIE_SECURE,
        samesite=settings.COOKIE_SAMESITE,
        domain="localhost",  # Match the domain used when setting cookies
    )
    response.delete_cookie(
        key="refresh_token",
        httponly=True,
        secure=settings.COOKIE_SECURE,
        samesite=settings.COOKIE_SAMESITE,
        domain="localhost",  # Match the domain used when setting cookies
    )

    return {"message": "Successfully logged out"}


# OAuth2 endpoints
@router.get("/{provider}/authorize")
async def oauth_authorize(
    provider: str,
    oauth_service: Annotated[OAuthService, Depends(get_oauth_service)],
) -> dict[str, str]:
    """Get OAuth authorization URL."""
    try:
        # Generate secure state parameter
        state = oauth_service.generate_state()

        # Get authorization URL
        auth_url = oauth_service.get_authorization_url(provider, state)

    except HTTPException:
        raise
    except Exception as e:
        logger.exception("OAuth authorization failed for provider: %s", provider)
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="OAuth authorization failed",
        ) from e
    else:
        return {
            "authorization_url": auth_url,
            "state": state,
        }


@router.get("/{provider}/callback")
async def oauth_callback(
    provider: str,
    response: Response,
    code: Annotated[str, Query()],
    oauth_service: Annotated[OAuthService, Depends(get_oauth_service)],
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
) -> RedirectResponse:
    """Handle OAuth callback."""
    try:
        logger.info("OAuth callback started for provider: %s", provider)

        # Handle OAuth callback and get user info
        oauth_user_info = await oauth_service.handle_callback(provider, code)

        # Perform OAuth login (link or create user)
        auth_response = await auth_service.oauth_login(oauth_user_info)

        # Create and store refresh token
        user = await auth_service.get_current_user(auth_response.user.id)
        refresh_token = await auth_service.create_and_store_refresh_token(user)

        # Set HTTP-only cookies for both tokens (not used due to cross-port issues)
        # These cookies are kept for potential future same-origin scenarios

        set_auth_cookies(
            response=response,
            access_token=auth_response.token.access_token,
            refresh_token=refresh_token,
            expires_in=auth_response.token.expires_in,
            path="/",  # Ensure cookie is available for all paths
        )

        logger.info(
            "OAuth login successful for user: %s via %s",
            auth_response.user.email,
            provider,
        )

        # Instead of setting cookies that won't work across ports,
        # let's redirect to a special frontend endpoint that can make an
        # immediate API call. Frontend will call /exchange-oauth-token with this code
        temp_code = secrets.token_urlsafe(32)

        # Store the mapping temporarily (in production, use Redis with TTL)
        # For now, store in memory with the user data
        _temp_oauth_codes[temp_code] = {
            "user_id": auth_response.user.id,
            "access_token": auth_response.token.access_token,
            "refresh_token": refresh_token,
            "expires_in": auth_response.token.expires_in,
            "created_at": time.time(),
        }

        redirect_url = f"http://localhost:8001/auth/callback?code={temp_code}"
        logger.info("Redirecting to: %s", redirect_url)

        return RedirectResponse(
            url=redirect_url,
            status_code=302,
        )

    except HTTPException:
        raise
    except Exception as e:
        logger.exception("OAuth callback failed for provider: %s", provider)
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="OAuth callback failed",
        ) from e


@router.get("/providers")
async def get_oauth_providers() -> dict[str, list[str]]:
    """Get list of available OAuth providers."""
    return {
        "providers": ["google", "github"],
    }


@router.post("/exchange-oauth-token")
async def exchange_oauth_token(
    request: dict[str, str],
    response: Response,
) -> dict[str, str]:
    """Exchange temporary OAuth code for proper auth cookies."""
    code = request.get("code")
    if not code:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Code parameter is required",
        )

    logger.info("OAuth token exchange requested with code: %s", code[:10] + "...")

    # Get the stored token data
    if code not in _temp_oauth_codes:
        logger.error("Invalid or expired OAuth code: %s", code[:10] + "...")
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Invalid or expired OAuth code",
        )

    token_data = _temp_oauth_codes.pop(code)  # Remove after use

    # Check if code is too old (5 minutes max)
    code_expiry_seconds = 300
    if time.time() - token_data["created_at"] > code_expiry_seconds:
        logger.error("OAuth code expired: %s", code[:10] + "...")
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="OAuth code expired",
        )

    # Set the proper auth cookies
    set_auth_cookies(
        response=response,
        access_token=token_data["access_token"],
        refresh_token=token_data["refresh_token"],
        expires_in=token_data["expires_in"],
        path="/",
    )

    user_id = token_data["user_id"]
    logger.info("OAuth tokens exchanged successfully for user: %s", user_id)
    return {"message": "Tokens set successfully", "user_id": str(user_id)}


# API Token endpoints
@router.post("/api-token")
async def generate_api_token(
    request: ApiTokenRequest,
    current_user: Annotated[User, Depends(get_current_active_user)],
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
) -> ApiTokenResponse:
    """Generate a new API token for the current user."""
    try:
        api_token = await auth_service.generate_api_token(
            current_user,
            expires_days=request.expires_days,
        )

        # Refresh user to get updated token info
        await auth_service.session.refresh(current_user)

        return ApiTokenResponse(
            api_token=api_token,
            expires_at=current_user.api_token_expires_at,
        )
    except Exception as e:
        logger.exception(
            "Failed to generate API token for user: %s",
            current_user.email,
        )
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Failed to generate API token",
        ) from e


@router.get("/api-token/status")
async def get_api_token_status(
    current_user: Annotated[User, Depends(get_current_active_user)],
) -> ApiTokenStatusResponse:
    """Get the current user's API token status."""
    has_token = current_user.api_token is not None
    is_expired = False

    if has_token and current_user.api_token_expires_at:
        is_expired = TokenUtils.is_token_expired(current_user.api_token_expires_at)

    return ApiTokenStatusResponse(
        has_token=has_token,
        expires_at=current_user.api_token_expires_at,
        is_expired=is_expired,
    )


@router.delete("/api-token")
async def revoke_api_token(
    current_user: Annotated[User, Depends(get_current_active_user)],
    auth_service: Annotated[AuthService, Depends(get_auth_service)],
) -> dict[str, str]:
    """Revoke the current user's API token."""
    try:
        await auth_service.revoke_api_token(current_user)
    except Exception as e:
        logger.exception(
            "Failed to revoke API token for user: %s",
            current_user.email,
        )
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="Failed to revoke API token",
        ) from e
    else:
        return {"message": "API token revoked successfully"}