from typing import List, Optional

from authlib.oauth2 import OAuth2Error
from flask import Flask, g, jsonify, request
from flask.typing import ResponseReturnValue

from owslib import auth
from owslib.enums import Environment
from owslib.urlpath import is_path_match


class JWTAuth:
    def __init__(
        self,
        environment: Environment = Environment.PROD,
        enabled: Optional[bool] = None,
        cache_timeout: Optional[int] = auth.DEFAULT_CACHE_TIMEOUT,
        realm: Optional[str] = None,
        exclude_paths: Optional[List[str]] = None,
    ) -> None:
        self.enabled = auth.jwt_auth_enabled_for_env(environment, enabled=enabled)
        self.exclude_paths = exclude_paths
        self.auth = auth.jwt_auth_from_config(
            environment, cache_timeout=cache_timeout, realm=realm
        )

    def init_app(self, app: Flask) -> None:
        if self.enabled:
            app.before_request(self.authenticate_request)

    def authenticate_request(self) -> Optional[ResponseReturnValue]:
        if is_path_match(request.path, match=self.exclude_paths):
            return None
        authorization = request.headers.get("authorization")
        try:
            token = self.auth.authenticate(authorization)
        except OAuth2Error as exc:
            return (
                jsonify(
                    code=exc.error or "Authentication error",
                    message=exc.get_error_description(),
                    detail={},
                ),
                exc.status_code,
                dict(exc.get_headers()),
            )
        g.token = token
        return None