// Copyright Inrupt Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to use,
// copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
// Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

/**
 * @hidden
 * @packageDocumentation
 */

import type {
  IIncomingRedirectHandler,
  ISessionInfo,
} from "@inrupt/solid-client-authn-core";
import { EVENTS } from "@inrupt/solid-client-authn-core";
import type { EventEmitter } from "events";

import { getUnauthenticatedSession } from "../../../sessionInfo/SessionInfoManager";

/**
 * This class handles redirect IRIs without any query params, and returns an unauthenticated
 * session. It serves as a fallback so that consuming libraries don't have to test
 * for the query params themselves, and can always try to use them as a redirect IRI.
 * @hidden
 */
export class ErrorOidcHandler implements IIncomingRedirectHandler {
  async canHandle(redirectUrl: string): Promise<boolean> {
    try {
      return new URL(redirectUrl).searchParams.has("error");
    } catch (e) {
      throw new Error(
        `[${redirectUrl}] is not a valid URL, and cannot be used as a redirect URL: ${e}`,
      );
    }
  }

  async handle(
    redirectUrl: string,
    eventEmitter?: EventEmitter,
  ): Promise<ISessionInfo & { fetch: typeof fetch }> {
    if (eventEmitter !== undefined) {
      const url = new URL(redirectUrl);
      const errorUrl = url.searchParams.get("error");
      const errorDescriptionUrl = url.searchParams.get("error_description");
      eventEmitter.emit(EVENTS.ERROR, errorUrl, errorDescriptionUrl);
    }
    return getUnauthenticatedSession();
  }
}