#!/usr/bin/env python3
# -*- encoding: utf-8 -*-

import datetime
import urllib.parse
import uuid

from constants import ALGORITHM, JWT_SECRET_KEY, TWITCH_CLIENT_ID, config
from fastapi import HTTPException, status
from fastapi.security import OAuth2AuthorizationCodeBearer
from jose import jwt
from models import (TokenPayloadModel, TokenUserWithPermissionsModel,
                    UserPermissionsModel)
from pydantic import ValidationError


def generate_twitch_login_link():
    return ("https://id.twitch.tv/oauth2/authorize" +
            "?response_type=token" +
            "&force_verify=false" +
            f"&client_id={TWITCH_CLIENT_ID}" +
            f"&redirect_uri={urllib.parse.quote(config['app']['root']+'/callback/twitch')}" +
            "&scope=" +
            f"&state={uuid.uuid4().hex}" +
            '')


reuseable_oauth = OAuth2AuthorizationCodeBearer(
    authorizationUrl=generate_twitch_login_link(),
    tokenUrl='/login/twitch',
    scheme_name="JWT",
)


def parse_token(token: str) -> 'TokenPayloadModel':
    try:
        payload = jwt.decode(
            token, JWT_SECRET_KEY, algorithms=[ALGORITHM]
        )
        token_data: TokenPayloadModel = TokenPayloadModel(**payload)
        if datetime.datetime.fromisoformat(token_data.expiration) < datetime.datetime.now():
            raise HTTPException(
                status_code=status.HTTP_401_UNAUTHORIZED,
                detail="token_expired",
                headers={"WWW-Authenticate": "Bearer"},
            )
        return token_data
    except (jwt.JWTError, ValidationError):
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="could_not_validate_credentials",
            headers={"WWW-Authenticate": "Bearer"},
        )


def user_permissions(token_data: 'TokenPayloadModel') -> 'UserPermissionsModel':
    is_streamer = config['app']['streamer'].strip() in [
        f'{token_data.platform}:{token_data.id}',
        f'{token_data.platform}:{token_data.login}',
    ]
    return UserPermissionsModel(is_admin=is_streamer)


def user_with_permissions(token_data: 'TokenPayloadModel') -> 'TokenUserWithPermissionsModel':
    permissions = user_permissions(token_data)
    return TokenUserWithPermissionsModel(
        user=token_data,
        permissions=permissions,
    )


def parse_token_with_permissions(token: str) -> 'TokenUserWithPermissionsModel':
    return user_with_permissions(parse_token(token))