import { Context, NarrowedContext, Telegraf } from 'telegraf';
import { message } from 'telegraf/filters';
import { ChatFromGetChat, Update } from 'telegraf/typings/core/types/typegram';
import { ioc } from './utils/ioc';
import { AudienceChangeController, audienceChangeSymbol } from './controllers/audienceChange';
import { log } from './utils/log';

export type ChannelInfo = {
  chatId: number,
  memberCount: number,
};

export type MessageInfo = {

};

export class ChannelBot {
  private readonly bot: Telegraf;

  constructor(
    private readonly token: string,
  ) {

    this.bot = new Telegraf(
      process.env.TELEGRAM_BOT_TOKEN ?? '',
    );

  }

  public async connect(): Promise<void> {

    process.once('SIGINT', () => this.bot.stop('SIGINT'));
    process.once('SIGTERM', () => this.bot.stop('SIGTERM'));

    this.bot.on('chat_member', this.handleChatMemberUpdate.bind(this));
    
    this.bot.launch(
      {
        allowedUpdates: [
          'chat_join_request',
          'chat_member',
          'channel_post',
          'edited_channel_post',
          'poll',
          'poll_answer'
        ],
      },
    );
  }

  private async handleChatMemberUpdate(ctx: NarrowedContext<Context<Update>, Update.ChatMemberUpdate>): Promise<void> {
    try {
      log.bot.info('chat_member event', JSON.stringify(ctx.chatMember));

      const change = ctx.chatMember;
      const status = change.new_chat_member.status;
      const statusBefore = change.old_chat_member.status;
      const role = ['restricted', 'left', 'kicked'].includes(status)
        ? statusBefore
        : status;

      const ctrl = ioc.get<AudienceChangeController>(audienceChangeSymbol);

      const chatMemberCount = await this.bot.telegram.getChatMembersCount(change.chat.id);

      ctrl.add({
        channelId: change.chat.id,
        user: {
          id: change.new_chat_member.user.id,
          username: change.new_chat_member.user.username,
          firstName: change.new_chat_member.user.first_name,
          lastName: change.new_chat_member.user.last_name,
          isBot: change.new_chat_member.user.is_bot,
          isPremium: change.new_chat_member.user.is_premium ? true : false,
          role,
        },
        timestamp: new Date(change.date * 1000),
        status,
        statusBefore,
        invitedByLink: change.invite_link?.invite_link ?? undefined,

        memberCountAfter: chatMemberCount,
      });
    }
    catch (err) {
      log.bot.error('chat member change processing error', err);
    }
  }

  public async getChannelInfo(channelId: number): Promise<ChannelInfo> {

    const memberCount = await this.bot.telegram.getChatMembersCount(channelId);

    const info: ChatFromGetChat = await this.bot.telegram.getChat(channelId);

    return {
      chatId: info.id,
      memberCount,
    };
  }
}

// bot.on('channel_post', async (ctx) => {
//   console.log('channel_post');
//   console.dir(ctx.channelPost.chat.id);

//   await sendChannelStats(ctx.chat.id);
// });