import os
from crypt import crypt
from functools import lru_cache

from fastapi import Depends, HTTPException, status
from fastapi.security import HTTPBasic, HTTPBasicCredentials

from . import config

security = HTTPBasic()


@lru_cache()
def get_settings():
    return config.Settings


def validate(username: str, password: str, settings: config.Settings):
    here = os.path.abspath(os.path.dirname(__file__))
    file = os.path.join(here, '../', settings.htpasswd)
    if not os.path.isfile(file):
        return None
    users = {}
    with open(file, "r") as f:
        for line in f:
            login, pwd = line.split(":")
            users[login] = pwd.rstrip("\n")
    if username in users:
        return crypt(password, users[username]) == users[username]
    else:
        return False


def get_current_username(
    credentials: HTTPBasicCredentials = Depends(security),
    settings: config.Settings = Depends(get_settings),
):
    if not validate(credentials.username, credentials.password, settings):
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Incorrect email or password",
            headers={"WWW-Authenticate": "Basic"},
        )
    return credentials.username