import logging
from datetime import datetime, timedelta, timezone
from typing import Annotated, Dict, List, Optional

import bcrypt
from fastapi import Depends, HTTPException, Request, Security, status
from fastapi.openapi.models import OAuthFlows as OAuthFlowsModel
from fastapi.security import OAuth2, OAuth2PasswordBearer, SecurityScopes
from fastapi.security.utils import get_authorization_scheme_param
from jose import JWTError, jwt
from pydantic import ValidationError

from src.core.config import settings
from src.core.log_conf import logger
from src.db.models.admin import Profile
from src.db.repository.admin import get_profile, is_database_empty
from src.db.session import SessionLocal
from src.schema.admin import ProfileModel, TokenData

oauth2_scheme = OAuth2PasswordBearer(
    tokenUrl="/api/login/token",
    scopes={"me": "read", "admin": "read"},
)


class OAuth2PasswordBearerWithCookie(OAuth2):
    def __init__(
        self,
        tokenUrl: str,
        scheme_name: Optional[str] = None,
        scopes: Optional[Dict[str, str]] = None,
        auto_error: bool = True,
    ):
        if not scopes:
            scopes = {}
        flows = OAuthFlowsModel(password={"tokenUrl": tokenUrl, "scopes": scopes})  # type: ignore
        super().__init__(flows=flows, scheme_name=scheme_name, auto_error=auto_error)

    async def __call__(self, request: Request) -> Optional[str]:
        authorization: str = request.cookies.get("access_token") # changed to accept access token from httpOnly Cookie
 
        scheme, param = get_authorization_scheme_param(authorization)
        if not authorization or scheme.lower() != "bearer":
            if self.auto_error:
                raise HTTPException(
                    status_code=status.HTTP_401_UNAUTHORIZED,
                    detail="Not authenticated",
                    headers={"WWW-Authenticate": "Bearer"},
                )
            else:
                return None
        return param


def authenticate_user(username: str, password: str) -> Optional[Profile]:
    with SessionLocal() as db:
        user = get_profile(username=username, db=db)
    logger.debug(user)
    if not user:
        if is_database_empty(db):
            logger.info("database is empty, use temporary access")
            user = Profile()
            user.email = "init_user@thpeetz.de"
            return user
        return None
    else:
        if bcrypt.checkpw(password.encode(), user.password.encode()):
            logger.info("User successful authenticated")
        else:
            logger.info("Authentication failed!")
    return user


def create_access_token(data: dict, expires_delta: Optional[timedelta] = None):
    to_encode = data.copy()
    if expires_delta:
        expire = datetime.now(timezone.utc) + expires_delta
    else:
        expire = datetime.now(timezone.utc) + timedelta(
            minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES
        )
    to_encode.update({"exp": expire})
    encoded_jwt = jwt.encode(
        to_encode, settings.SECRET_KEY, algorithm=settings.ALGORITHM
    )
    return encoded_jwt


async def get_current_user(
    security_scopes: SecurityScopes, token: Annotated[str, Depends(oauth2_scheme)]
):
    if security_scopes.scopes:
        authenticate_value = f'Bearer scope="{security_scopes.scope_str}"'
    else:
        authenticate_value = "Bearer"
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
        headers={"WWW-Authenticate": authenticate_value},
    )
    try:
        payload = jwt.decode(
            token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM]
        )
        username: str = payload.get("sub")  # type: ignore
        logger.info("username/email extracted is %s", username)
        if username is None:
            raise credentials_exception
        scope: str = payload.get("scope", "")
        token_scopes: List[str] = scope.split(" ")
        token_data = TokenData(scopes=token_scopes, username=username)
    except (JWTError, ValidationError):
        raise credentials_exception
    with SessionLocal() as db:
        user = get_profile(username=token_data.username, db=db)  # type: ignore
    if user is None:
        raise credentials_exception
    for scope in security_scopes.scopes:
        if scope not in token_scopes:
            raise HTTPException(
                status_code=status.HTTP_401_UNAUTHORIZED,
                detail="not enough permissions",
                headers={"WWW-Authenticate": authenticate_value},
            )
    return user


async def get_current_active_user(
    current_user: Annotated[Profile, Security(get_current_user, scopes=["me"])],
) -> ProfileModel:
    if not current_user.enabled:  # type: ignore
        raise HTTPException(status_code=400, detail="Inactive user")
    user_model = ProfileModel(
        username=current_user.user_name,
        email=current_user.email,  # type: ignore
        first_name=current_user.first_name,
        last_name=current_user.last_name,  # type: ignore
        active=current_user.enabled,
    )  # type: ignore
    return user_model


def get_current_user_from_token(token: str = Depends(oauth2_scheme)):
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
    )
    try:
        payload = jwt.decode(
            token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM]
        )
        username: str = payload.get("sub")  # type: ignore
        logger.info("username/email extracted is %s", username)
        if username is None:
            raise credentials_exception
    except JWTError:
        raise credentials_exception
    with SessionLocal() as db:
        user = get_profile(username=username, db=db)
    if user is None:
        raise credentials_exception
    return user