import {
  getAllOpenGroupV2Conversations,
  getAllV2OpenGroupRooms,
  OpenGroupV2Room,
  removeV2OpenGroupRoom,
  saveV2OpenGroupRoom,
} from '../../data/opengroups';
import { ConversationModel, ConversationTypeEnum } from '../../models/conversation';
import { ConversationController } from '../../session/conversations';
import { allowOnlyOneAtATime } from '../../session/utils/Promise';
import { getOpenGroupV2ConversationId } from '../utils/OpenGroupUtils';
import { OpenGroupRequestCommonType } from './ApiUtil';
import { openGroupV2GetRoomInfo } from './OpenGroupAPIV2';
import { OpenGroupServerPoller } from './OpenGroupServerPoller';

import _ from 'lodash';
import { deleteAuthToken } from './ApiAuth';

export class OpenGroupManagerV2 {
  public static readonly useV2OpenGroups = false;

  private static instance: OpenGroupManagerV2;

  /**
   * The map of opengroup pollers, by serverUrl.
   * A single poller polls for every room on the specified serverUrl
   */
  private readonly pollers: Map<string, OpenGroupServerPoller> = new Map();
  private isPolling = false;

  private constructor() {
    this.startPollingBouncy = this.startPollingBouncy.bind(this);
    this.attemptConnectionV2 = this.attemptConnectionV2.bind(this);
  }

  public static getInstance() {
    if (!OpenGroupManagerV2.instance) {
      OpenGroupManagerV2.instance = new OpenGroupManagerV2();
    }
    return OpenGroupManagerV2.instance;
  }

  /**
   * When we get our configuration from the network, we might get a few times the same open group on two different messages.
   * If we don't do anything, we will join them multiple times.
   * Even if the convo exists only once, the lokiPublicChat API will have several instances polling for the same open group.
   * Which will cause a lot of duplicate messages as they will be merged on a single conversation.
   *
   * To avoid this issue, we allow only a single join of a specific opengroup at a time.
   */
  public async attemptConnectionV2OneAtATime(
    serverUrl: string,
    roomId: string,
    publicKey: string
  ): Promise<ConversationModel> {
    const oneAtaTimeStr = `oneAtaTimeOpenGroupV2Join:${serverUrl}${roomId}`;
    return allowOnlyOneAtATime(oneAtaTimeStr, async () => {
      return this.attemptConnectionV2(serverUrl, roomId, publicKey);
    });
  }

  public async startPolling() {
    await allowOnlyOneAtATime('V2ManagerStartPolling', this.startPollingBouncy);
  }

  /**
   * This is not designed to be restarted for now. If you stop polling
   */
  public stopPolling() {
    if (!this.isPolling) {
      return;
    }
    // the stop call calls the abortController, which will effectively cancel the request right away,
    // or drop the result from it.
    this.pollers.forEach(poller => {
      poller.stop();
    });
    this.pollers.clear();

    this.isPolling = false;
  }

  public addRoomToPolledRooms(roomInfos: OpenGroupRequestCommonType) {
    const poller = this.pollers.get(roomInfos.serverUrl);
    if (!poller) {
      this.pollers.set(roomInfos.serverUrl, new OpenGroupServerPoller([roomInfos]));
      return;
    }
    // this won't do a thing if the room is already polled for
    poller.addRoomToPoll(roomInfos);
  }

  public removeRoomFromPolledRooms(roomInfos: OpenGroupRequestCommonType) {
    const poller = this.pollers.get(roomInfos.serverUrl);
    if (!poller) {
      return;
    }
    // this won't do a thing if the room is already polled for
    poller.removeRoomFromPoll(roomInfos);
    if (poller.getPolledRoomsCount() === 0) {
      this.pollers.delete(roomInfos.serverUrl);
      // this poller is not needed anymore, kill it
      poller.stop();
    }
  }

  /**
   * This function is private because we want to make sure it only runs once at a time.
   */
  private async startPollingBouncy() {
    if (this.isPolling) {
      return;
    }
    const allConvos = await getAllOpenGroupV2Conversations();
    let allRoomInfos = await getAllV2OpenGroupRooms();

    // this is time for some cleanup!
    // We consider the conversations are our source-of-truth,
    // so if there is a roomInfo without an associated convo, we remove it
    if (allRoomInfos) {
      await Promise.all(
        [...allRoomInfos.values()].map(async infos => {
          try {
            const roomConvoId = getOpenGroupV2ConversationId(infos.serverUrl, infos.roomId);
            if (!allConvos.get(roomConvoId)) {
              // leave the group on the remote server
              // this request doesn't throw
              await deleteAuthToken(_.pick(infos, 'serverUrl', 'roomId'));
              // remove the roomInfos locally for this open group room
              await removeV2OpenGroupRoom(roomConvoId);
              // no need to remove it from the ConversationController, the convo is already not there
            }
          } catch (e) {
            window.log.warn('cleanup roomInfos error', e);
          }
        })
      );
    }
    // refresh our roomInfos list
    allRoomInfos = await getAllV2OpenGroupRooms();
    if (allRoomInfos) {
      allRoomInfos.forEach(infos => {
        this.addRoomToPolledRooms(infos);
      });
    }

    this.isPolling = true;
  }

  /**
   *
   * @param serverUrl with protocol, hostname and port included
   */
  private async attemptConnectionV2(
    serverUrl: string,
    roomId: string,
    serverPublicKey: string
  ): Promise<ConversationModel | undefined> {
    const conversationId = getOpenGroupV2ConversationId(serverUrl, roomId);

    if (ConversationController.getInstance().get(conversationId)) {
      // Url incorrect or server not compatible
      throw new Error(window.i18n('publicChatExists'));
    }

    // here, the convo does not exist. Make sure the db is clean too
    await removeV2OpenGroupRoom(conversationId);

    const room: OpenGroupV2Room = {
      serverUrl,
      roomId,
      conversationId,
      serverPublicKey,
    };

    try {
      // save the pubkey to the db right now, the request for room Info
      // will need it and access it from the db
      await saveV2OpenGroupRoom(room);
      const roomInfos = await openGroupV2GetRoomInfo({ roomId, serverUrl });
      if (!roomInfos) {
        throw new Error('Invalid open group roomInfo result');
      }
      const conversation = await ConversationController.getInstance().getOrCreateAndWait(
        conversationId,
        ConversationTypeEnum.GROUP
      );
      room.imageID = roomInfos.imageId || undefined;
      room.roomName = roomInfos.name || undefined;
      await saveV2OpenGroupRoom(room);

      // mark active so it's not in the contacts list but in the conversation list
      conversation.set({
        active_at: Date.now(),
        name: room.roomName,
        avatarPath: room.roomName,
      });
      await conversation.commit();

      // start polling this room
      this.addRoomToPolledRooms(room);

      return conversation;
    } catch (e) {
      window.log.warn('Failed to join open group v2', e);
      await removeV2OpenGroupRoom(conversationId);
      throw new Error(window.i18n('connectToServerFail'));
    }
  }
}