// Copyright 2019-2023 Tauri Programme within The Commons Conservancy
// SPDX-License-Identifier: Apache-2.0
// SPDX-License-Identifier: MIT

/**
 * Make HTTP requests with the Rust backend.
 *
 * ## Security
 *
 * This API has a scope configuration that forces you to restrict the URLs and paths that can be accessed using glob patterns.
 *
 * For instance, this scope configuration only allows making HTTP requests to the GitHub API for the `tauri-apps` organization:
 * ```json
 * {
 *   "plugins": {
 *     "http": {
 *       "scope": ["https://api.github.com/repos/tauri-apps/*"]
 *     }
 *   }
 * }
 * ```
 * Trying to execute any API with a URL not configured on the scope results in a promise rejection due to denied access.
 *
 * @module
 */

import { invoke } from "@tauri-apps/api/core";

/**
 * Options to configure the Rust client used to make fetch requests
 *
 * @since 2.0.0
 */
export interface ClientOptions {
  /**
   * Defines the maximum number of redirects the client should follow.
   * If set to 0, no redirects will be followed.
   */
  maxRedirections?: number;
  /** Timeout in milliseconds */
  connectTimeout?: number;
}

/**
 * Fetch a resource from the network. It returns a `Promise` that resolves to the
 * `Response` to that `Request`, whether it is successful or not.
 *
 * @example
 * ```typescript
 * const response = await fetch("http://my.json.host/data.json");
 * console.log(response.status);  // e.g. 200
 * console.log(response.statusText); // e.g. "OK"
 * const jsonData = await response.json();
 * ```
 *
 * @since 2.0.0
 */
export async function fetch(
  input: URL | Request | string,
  init?: RequestInit & ClientOptions,
): Promise<Response> {
  const maxRedirections = init?.maxRedirections;
  const connectTimeout = init?.maxRedirections;

  // Remove these fields before creating the request
  if (init) {
    delete init.maxRedirections;
    delete init.connectTimeout;
  }

  const req = new Request(input, init);
  const buffer = await req.arrayBuffer();
  const reqData = buffer.byteLength ? Array.from(new Uint8Array(buffer)) : null;

  const rid = await invoke<number>("plugin:http|fetch", {
    method: req.method,
    url: req.url,
    headers: Array.from(req.headers.entries()),
    data: reqData,
    maxRedirections,
    connectTimeout,
  });

  req.signal.addEventListener("abort", () => {
    invoke("plugin:http|fetch_cancel", {
      rid,
    });
  });

  interface FetchSendResponse {
    status: number;
    statusText: string;
    headers: [[string, string]];
    url: string;
  }

  const { status, statusText, url, headers } = await invoke<FetchSendResponse>(
    "plugin:http|fetch_send",
    {
      rid,
    },
  );

  const body = await invoke<number[]>("plugin:http|fetch_read_body", {
    rid,
  });

  const res = new Response(new Uint8Array(body), {
    headers,
    status,
    statusText,
  });

  // url is read only but seems like we can do this
  Object.defineProperty(res, "url", { value: url });

  return res;
}