"""
Module specific business logic for the auth module

Exports:
 - claims_dependency: Dict[str, Any] containing OIDC claims and database ID
"""
import json
import requests

from typing import Annotated, Any
from joserfc import jwt
from joserfc.errors import ExpiredTokenError
from joserfc.jwk import KeySet
from urllib.request import urlopen

from fastapi import Depends
from fastapi.security import OpenIdConnect

from src.auth.exceptions import UnauthorizedException
from src.auth.config import auth_settings
from src.user.service import add_user_to_db
from src.database import db_dependency


oidc = OpenIdConnect(openIdConnectUrl=auth_settings.OIDC_CONFIG)
oidc_dependency = Annotated[str, Depends(oidc)]

def get_dev_user():
	return {"db_id": 1}


async def get_current_user(oidc_auth_string: oidc_dependency, db: db_dependency) -> dict[str, Any]:
	config_url = urlopen(auth_settings.OIDC_CONFIG)
	config = json.loads(config_url.read())
	jwks_uri = config["jwks_uri"]
	key_response = requests.get(jwks_uri)
	jwk_keys = KeySet.import_key_set(key_response.json())

	claims_options = {
		"exp": {"essential": True},
		"iss": {"essential": True, "value": auth_settings.OIDC_ISSUER},
	}

	token = jwt.decode(
		oidc_auth_string.replace("Bearer ", ""),
		jwk_keys
	)

	claims_requests = jwt.JWTClaimsRegistry(**claims_options)

	try:
		claims_requests.validate(token.claims)
	except ExpiredTokenError:
		raise UnauthorizedException(message="Token is expired")
	db_id = await add_user_to_db(db, token.claims)

	token.claims["db_id"] = db_id

	return token.claims


claims_dependency = Annotated[dict[str, Any], Depends(get_current_user)]