from datetime import UTC, datetime, timedelta
from typing import Annotated

import jwt
from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from pwdlib import PasswordHash

from app.config import Settings
from app.database import get_from_database_where
from app.models.token import TokenData
from app.models.user import User, UserInDB

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

password_hash = PasswordHash.recommended()

DUMMY_HASH = password_hash.hash("testpassword")


def verify_password(plain_password: str, hashed_password: str):
    return password_hash.verify(plain_password, hashed_password)


def get_password_hash(password: str):
    return password_hash.hash(password)


def get_user(username: str):
    user_dict = get_from_database_where(User, User.username, username, True)
    if user_dict is not None:
        return UserInDB(**user_dict)


def authenticate_user(username: str, password: str):
    user = get_user(username)
    if not user:
        verify_password(password, DUMMY_HASH)
        return False
    if not verify_password(password, user.hashed_password):
        return False
    return user


def create_access_token(
    data: dict[str, str],
    expires_delta: timedelta | None = None,
):
    to_encode = data.copy()
    if expires_delta:
        expire = datetime.now(UTC) + expires_delta
    else:
        expire = datetime.now(UTC) + timedelta(minutes=15)
    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(token: Annotated[str, Depends(oauth2_scheme)]):
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(
            token,
            Settings.secret_key,
            algorithms=[Settings.algorithm],
        )
        username = payload.get("sub")
        if username is None:
            raise credentials_exception
        token_data = TokenData(username=username)
    except jwt.InvalidTokenError:
        raise credentials_exception
    user = get_user(token_data.username)  # type: ignore Look just above here idiot!
    if user is None:
        raise credentials_exception
    return user


async def get_current_active_user(
    current_user: Annotated[User, Depends(get_current_user)],
):
    return current_user