from datetime import datetime, timedelta, timezone
from typing import Optional
from jose import JWTError, jwt
from authlib.integrations.starlette_client import OAuth
from fastapi import Cookie, HTTPException, status, Depends
from sqlalchemy.orm import Session
from app.database import get_db, settings
from app import models

oauth = OAuth()
oauth.register(
    name="keycloak",
    client_id=settings.keycloak_client_id,
    client_secret=settings.keycloak_client_secret,
    server_metadata_url=(
        f"{settings.keycloak_url}/realms/{settings.keycloak_realm}"
        "/.well-known/openid-configuration"
    ),
    client_kwargs={"scope": "openid email profile"},
)


def create_access_token(user_id: int) -> str:
    expire = datetime.now(timezone.utc) + timedelta(minutes=settings.jwt_expire_minutes)
    return jwt.encode(
        {"sub": str(user_id), "exp": expire},
        settings.jwt_secret_key,
        algorithm=settings.jwt_algorithm,
    )


def get_current_user(
    access_token: Optional[str] = Cookie(default=None),
    db: Session = Depends(get_db),
) -> models.User:
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Not authenticated",
    )
    if not access_token:
        raise credentials_exception
    try:
        payload = jwt.decode(access_token, settings.jwt_secret_key, algorithms=[settings.jwt_algorithm])
        user_id: str = payload.get("sub")
        if user_id is None:
            raise credentials_exception
    except JWTError:
        raise credentials_exception

    user = db.get(models.User, int(user_id))
    if user is None or not user.is_active:
        raise credentials_exception
    return user


def get_optional_user(
    access_token: Optional[str] = Cookie(default=None),
    db: Session = Depends(get_db),
) -> Optional[models.User]:
    if not access_token:
        return None
    try:
        return get_current_user(access_token=access_token, db=db)
    except HTTPException:
        return None