import {
  Plugin,
  Configurable,
  EventListener,
  InjectService
} from '@squeebot/core/lib/plugin';

import util from 'util';

import {
  MatrixClient,
  AutojoinRoomsMixin,
  RichReply,
  SimpleFsStorageProvider,
  LogService,
  LogLevel,
} from 'matrix-bot-sdk';

import { logger } from '@squeebot/core/lib/core';
import {
  EMessageType,
  Formatter,
  HTMLFormatter,
  IMessage,
  IMessageTarget,
  Protocol
} from '@squeebot/core/lib/types';

class MatrixMessageAdapter implements IMessage {
  public time: Date = new Date();
  public resolved = false;
  public direct = false;

  constructor(
    public type: EMessageType,
    public data: any,
    public source: Protocol,
    public sender: IMessageTarget,
    public target?: IMessageTarget) {}

  public get fullSenderID(): string {
    return this.source.fullName + '/' + this.sender.id;
  }

  public get fullRoomID(): string {
    if (!this.target) {
      return this.source.fullName;
    }

    return this.source.fullName + '/' + this.target.id;
  }

  public get text(): string {
    return this.data.content.body;
  }

  public resolve(...args: any[]): void {
    this.resolved = true;
    this.source.resolve(this, ...args);
  }

  public reject(error: Error): void {
    this.resolved = true;
    this.source.resolve(this, error.message);
  }

  public mention(user: IMessageTarget): string {
    return `<a href="https://matrix.to/#/${user.id}">${user.id}</a>`;
  }
}

class MatrixProtocol extends Protocol {
  public format: Formatter = new HTMLFormatter();
  public type = 'MatrixProtocol';
  public nameCache: Map<string, string> = new Map<string, string>();

  private client?: MatrixClient;

  public async handler(roomId: any, event: any): Promise<void> {
    // Don't handle events that don't have contents (they were probably redacted)
    if (!this.client || !this.me || !event.content) { return; }

    // Don't handle non-text events
    if (event.content.msgtype !== 'm.text') { return; }
    const msg = event.content.body;

    // filter out events sent by the bot itself
    if (event.sender === this.me.id || !msg) { return; }
    const senderName = await this.getUserDisplayName(event.sender);
    const roomName = await this.getRoomDisplayName(roomId);

    const newMessage = new MatrixMessageAdapter(
      EMessageType.message,
      event,
      this,
      { id: event.sender, name: senderName, },
      { id: roomId, name: roomName, }
    );
    this.plugin.stream.emitTo('channel', 'message', newMessage);
  }

  public async getUserDisplayName(id: string): Promise<string> {
    if (this.nameCache.has(id)) {
      return this.nameCache.get(id) as string;
    }
    const profile = await this.client?.getUserProfile(id);
    if (!profile || !profile.displayname) {
      return id;
    }
    this.nameCache.set(id, profile.displayname);
    return profile.displayname;
  }

  public async getRoomDisplayName(id: string): Promise<string> {
    if (this.nameCache.has(id)) {
      return this.nameCache.get(id) as string;
    }
    const roomState = await this.client?.getRoomStateEvent(id, 'm.room.name', '');
    if (!roomState || !roomState.name) {
      return id;
    }
    this.nameCache.set(id, roomState.name);
    return roomState.name;
  }

  private async getSelf(): Promise<void> {
    if (!this.client) {
      return;
    }

    const id = await this.client.getUserId();
    const name = await this.getUserDisplayName(id);

    this.me = { id, name };
  }

  public start(...args: any[]): void {
    const stpath = `.matrix-${this.config.name}.db.json`;
    const storage = new SimpleFsStorageProvider(stpath);

    this.client = new MatrixClient(this.config.homeserver, this.config.token, storage);
    AutojoinRoomsMixin.setupOnClient(this.client);
    LogService.setLevel(LogLevel.ERROR);

    this.client.on('room.message', (...dargs) =>
      this.handler(dargs[0], dargs[1])
      .catch(e => logger.error(e)));

    this.client.start()
      .then(() => {
        this.running = true;
        logger.info('[%s] Protocol "%s" ready', this.plugin.manifest.name, this.config.name);
        this.getSelf();
      })
      .catch((e) => {
        this.stop(true);
        logger.error('[%s] Protocol "%s" failed to start',
          this.plugin.manifest.name, this.config.name);
      });
  }

  public stop(force = false): void {
    if (!this.running && !force) {
      return;
    }

    if (this.client) {
      this.client.stop();
      this.client = undefined;
    }

    this.running = false;
    this.stopped = true;

    if (force) {
      this.failed = true;
    }

    this.emit('stopped');
  }

  public resolve(msg: MatrixMessageAdapter, ...data: any[]): void {
    let response = util.format(data[0], ...data.slice(1));
    if (!response || !msg.target) {
      return;
    }

    if (Array.isArray(data[0])) {
      try {
        response = this.format.compose(data[0]);
      } catch (e) {
        logger.error('[%s] Failed to compose message:', this.fullName, e.message);
        return;
      }
    }

    this.client?.sendMessage(msg.target.id, {
      msgtype: 'm.text',
      body: this.format.strip(response),
      format: 'org.matrix.custom.html',
      formatted_body: response.replace('\n', '<br />'),
    });
  }
}

@InjectService(MatrixProtocol)
@Configurable({instances: []})
class MatrixServicePlugin extends Plugin {
  initialize(): void {
    const protoList = this.validateConfiguration();
    this.startAll(protoList);
  }

  private startAll(list: any[]): void {
    for (const ins of list) {
      const newProto = new MatrixProtocol(this, ins);
      logger.log('[%s] Starting Matrix service "%s".', this.name, ins.name);
      this.monitor(newProto);
      this.service?.use(newProto, true);
    }
  }

  private monitor(proto: Protocol): void {
    proto.on('running', () => this.emit('protocolNew', proto));
    proto.on('stopped', () => this.emit('protocolExit', proto));
  }

  private validateConfiguration(): any[] {
    if (!this.config.config.instances) {
      throw new Error('Configuration incomplete!');
    }

    const instances = this.config.config.instances;
    const runnables: any[] = [];
    for (const ins of instances) {
      if (ins.enabled === false) {
        continue;
      }

      if (!ins.name || !ins.token || !ins.homeserver) {
        throw new Error('Invalid instance configuration!');
      }

      runnables.push(ins);
    }

    return runnables;
  }

  @EventListener('pluginUnload')
  public unloadEventHandler(plugin: string | Plugin): void {
    if (plugin === this.name || plugin === this) {
      this.config.save().then(() =>
        this.service?.stopAll().then(() =>
        this.emit('pluginUnloaded', this)));
    }
  }
}

module.exports = MatrixServicePlugin;