/*---------------------------------------------------------------------------------------------
 * Copyright (c) Bentley Systems, Incorporated. All rights reserved.
 * See LICENSE.md in the project root for license terms and full copyright notice.
 *--------------------------------------------------------------------------------------------*/
import type { EC3ConfigPropsWithRedirectUri } from "./EC3Config";
import { getDefaultEC3Uri } from "./EC3Config";
import type { EC3Token } from "./EC3Token";

/* This function must be called in EC3 authentication redirect path.
 *
 * Example:
 * } else if (window.location.pathname === "/callback") {
 *   handleEC3AuthCallback({
 *     clientId: "...",
 *     redirectUri: "http://localhost:8887/callback",
 *   });
 * } else {
 */

/**
 * EC3 Auth Callback Config Props
 * @beta
 */
export type EC3AuthCallbackConfigProps = Pick<EC3ConfigPropsWithRedirectUri, "clientId" | "redirectUri" | "ec3Uri">;

/**
 * Simple implementation to handle EC3 OAuth2 callback and exchange token
 * @beta
 */
export function handleEC3AuthCallback(ec3Config: EC3AuthCallbackConfigProps, source: string = "ec3-auth") {
  const MILLI_SECONDS = 1000;
  const ec3Uri = getDefaultEC3Uri(ec3Config.ec3Uri);

  async function exchangeToken() {
    const code = new URL(window.location.href).searchParams.get("code");
    const prop = {
      method: "POST",
      headers: {
        "Content-Type": "application/x-www-form-urlencoded",
      },
      body: `client_id=${ec3Config.clientId}&grant_type=authorization_code&code=${code}&redirect_uri=${ec3Config.redirectUri}`,
    };

    const response = await fetch(`${ec3Uri}api/oauth2/token`, prop);
    const tokenResponse = await response.json();
    const token: EC3Token = {
      token: tokenResponse.access_token,
      exp: Date.now() + tokenResponse.expires_in * MILLI_SECONDS,
      source,
    };

    const parentWindow = window.opener as Window;
    parentWindow.postMessage(token, window.location.origin);
  }

  void exchangeToken();
}