/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import {FunctionUtils} from 'common/function_utils';
import {
  BuganizerAttachmentsDownloadEmitter,
  OnBuganizerAttachmentsDownloaded,
  OnBuganizerAttachmentsDownloadStart,
} from 'interfaces/buganizer_attachments_download_emitter';
import {MessageType, OpenBuganizerResponse, OpenRequest, WebCommandMessage} from './messages';

export class AbtChromeExtensionProtocol implements BuganizerAttachmentsDownloadEmitter {
  static readonly ABT_EXTENSION_ID = 'mbbaofdfoekifkfpgehgffcpagbbjkmj';
  private onAttachmentsDownloadStart: OnBuganizerAttachmentsDownloadStart =
    FunctionUtils.DO_NOTHING;
  private onAttachmentsDownloaded: OnBuganizerAttachmentsDownloaded =
    FunctionUtils.DO_NOTHING_ASYNC;

  setOnBuganizerAttachmentsDownloadStart(callback: OnBuganizerAttachmentsDownloadStart) {
    this.onAttachmentsDownloadStart = callback;
  }

  setOnBuganizerAttachmentsDownloaded(callback: OnBuganizerAttachmentsDownloaded) {
    this.onAttachmentsDownloaded = callback;
  }

  run() {
    const urlParams = new URLSearchParams(window.location.search);
    if (urlParams.get('source') !== 'openFromExtension' || !chrome) {
      return;
    }

    this.onAttachmentsDownloadStart();

    const openRequestMessage: OpenRequest = {
      action: MessageType.OPEN_REQUEST,
    };

    chrome.runtime.sendMessage(
      AbtChromeExtensionProtocol.ABT_EXTENSION_ID,
      openRequestMessage,
      async (message) => await this.onMessageReceived(message)
    );
  }

  private async onMessageReceived(message: WebCommandMessage) {
    if (this.isOpenBuganizerResponseMessage(message)) {
      await this.onOpenBuganizerResponseMessageReceived(message);
    } else {
      console.warn('ABT chrome extension protocol received unexpected message:', message);
    }
  }

  private async onOpenBuganizerResponseMessageReceived(message: OpenBuganizerResponse) {
    console.log('ABT chrome extension protocol received OpenBuganizerResponse message:', message);

    if (message.attachments.length === 0) {
      console.warn('ABT chrome extension protocol received no attachments');
    }

    const filesBlobPromises = message.attachments.map(async (attachment) => {
      const fileQueryResponse = await fetch(attachment.objectUrl);
      const blob = await fileQueryResponse.blob();

      // Note: the received blob's media type is wrong. It is always set to "image/png".
      // Context: http://google3/javascript/closure/html/safeurl.js?g=0&l=256&rcl=273756987
      // Cloning the blob clears the media type.
      const file = new File([blob], attachment.name);

      return file;
    });

    const files = await Promise.all(filesBlobPromises);
    await this.onAttachmentsDownloaded(files);
  }

  private isOpenBuganizerResponseMessage(
    message: WebCommandMessage
  ): message is OpenBuganizerResponse {
    return message.action === MessageType.OPEN_BUGANIZER_RESPONSE;
  }
}