Q2TG/src/helpers/forwardHelper.ts

import { fetchFile } from '../utils/urls';
import { CustomFile } from 'telegram/client/uploads';
import { base64decode } from 'nodejs-base64';
import { getLogger } from 'log4js';
import { Entity } from 'telegram/define';
import { ForwardMessage } from 'icqq';
import { Api } from 'telegram';
import { imageSize } from 'image-size';

const log = getLogger('ForwardHelper');

const htmlEscape = (text: string) =>
  text.replace(/&/g, '&')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;');

export default {
  async downloadToCustomFile(url: string, allowWebp = false, filename?: string) {
    const { fileTypeFromBuffer } = await (Function('return import("file-type")')() as Promise<typeof import('file-type')>);
    const file = await fetchFile(url);
    if (filename) {
      return new CustomFile(filename, file.length, '', file);
    }
    const type = await fileTypeFromBuffer(file);
    // The photo must be at most 10 MB in size. The photo's width and height must not exceed 10000 in total. Width and height ratio must be at most 20
    if (type.ext === 'png' || type.ext === 'jpg') {
      const dimensions = imageSize(file);
      const aspectRatio = dimensions.width / dimensions.height;
      if (aspectRatio > 20 || aspectRatio < 1 / 20
        || dimensions.width + dimensions.height > 10000
      ) {
        // 让 Telegram 服务器下载
        return url
      }
    }
    if (allowWebp) {
      return new CustomFile(`image.${type.ext}`, file.length, '', file);
    }
    else {
      // 防止 webp 作为贴纸发送时丢失发送者信息
      return new CustomFile(`image.${type.ext === 'webp' ? 'png' : type.ext}`, file.length, '', file);
    }
  },

  hSize(size: number) {
    const BYTE = 1024;

    if (size < BYTE)
      return size + 'B';
    if (size < Math.pow(BYTE, 2))
      return (size / BYTE).toFixed(1) + 'KB';
    if (size < Math.pow(BYTE, 3))
      return (size / Math.pow(BYTE, 2)).toFixed(1) + 'MB';
    if (size < Math.pow(BYTE, 4))
      return (size / Math.pow(BYTE, 3)).toFixed(1) + 'GB';
    return (size / Math.pow(BYTE, 4)).toFixed(1) + 'TB';
  },

  htmlEscape,

  processJson(json: string) {
    const jsonObj = JSON.parse(json);
    if (jsonObj.app === 'com.tencent.mannounce') {
      try {
        const title = base64decode(jsonObj.meta.mannounce.title);
        const content = base64decode(jsonObj.meta.mannounce.text);
        return { type: 'text', text: title + '\n\n' + content };
      }
      catch (err) {
        log.error('解析群公告时出错', err);
        return { type: 'text', text: '[群公告]' };
      }
    }
    else if (jsonObj.app === 'com.tencent.multimsg') {
      try {
        const resId = jsonObj.meta?.detail?.resid;
        const fileName = jsonObj.meta?.detail?.uniseq;
        if (resId) {
          return { type: 'forward', resId };
        }
        else {
          return { type: 'text', text: '[解析转发消息时出错：没有 resId]' };
        }
      }
      catch (err) {
      }
    }
    let appurl: string;
    const biliRegex = /(https?:\\?\/\\?\/b23\.tv\\?\/\w*)\??/;
    const zhihuRegex = /(https?:\\?\/\\?\/\w*\.?zhihu\.com\\?\/[^?"=]*)\??/;
    const biliRegex2 = /(https?:\\?\/\\?\/\w*\.?bilibili\.com\\?\/[^?"=]*)\??/;
    const jsonLinkRegex = /{.*"app":"com.tencent.structmsg".*"jumpUrl":"(https?:\\?\/\\?\/[^",]*)".*}/;
    const jsonAppLinkRegex = /"contentJumpUrl": ?"(https?:\\?\/\\?\/[^",]*)"/;
    if (biliRegex.test(json))
      appurl = json.match(biliRegex)[1].replace(/\\\//g, '/');
    else if (biliRegex2.test(json))
      appurl = json.match(biliRegex2)[1].replace(/\\\//g, '/');
    else if (zhihuRegex.test(json))
      appurl = json.match(zhihuRegex)[1].replace(/\\\//g, '/');
    else if (jsonLinkRegex.test(json))
      appurl = json.match(jsonLinkRegex)[1].replace(/\\\//g, '/');
    else if (jsonAppLinkRegex.test(json))
      appurl = json.match(jsonAppLinkRegex)[1].replace(/\\\//g, '/');
    if (appurl) {
      return { type: 'text', text: appurl };
    }
    else {
      // TODO 记录无法解析的 JSON
      return { type: 'text', text: '[JSON]' };
    }
  },

  processXml(xml: string):
    { type: 'forward', resId: string } | { type: 'text', text: string } | { type: 'image', md5: string } {
    const urlRegex = /url="([^"]+)"/;
    const md5ImageRegex = /image md5="([A-F\d]{32})"/;
    let text: string;
    if (urlRegex.test(xml))
      text = xml.match(urlRegex)[1].replace(/\\\//g, '/');
    if (xml.includes('action="viewMultiMsg"')) {
      text = '[Forward multiple messages]';
      const resIdRegex = /m_resid="([\w+=/]+)"/;
      if (resIdRegex.test(xml)) {
        const resId = xml.match(resIdRegex)![1];
        return {
          type: 'forward',
          resId,
        };
      }
    }
    else if (text) {
      text = text.replace(/&amp;/g, '&');
      return {
        type: 'text',
        text,
      };
    }
    else if (md5ImageRegex.test(xml)) {
      const imgMd5 = xml.match(md5ImageRegex)![1];
      return {
        type: 'image',
        md5: imgMd5,
      };
    }
    else {
      return {
        type: 'text',
        text: '[XML]',
      };
    }
  },

  getUserDisplayName(user: Entity) {
    if (!user) {
      return '未知';
    }
    if ('firstName' in user) {
      return user.firstName +
        (user.lastName ? ' ' + user.lastName : '');
    }
    else if ('title' in user) {
      return user.title;
    }
    else if ('id' in user) {
      return user.id.toString();
    }
    return '未知';
  },

  generateForwardBrief(messages: ForwardMessage[]) {
    const count = messages.length;
    // 取前四条
    messages = messages.slice(0, 4);
    let result = '<b>转发的消息记录</b>';
    for (const message of messages) {
      result += `\n<b>${message.nickname}: </b>` +
        `${htmlEscape(message.raw_message.length > 10 ? message.raw_message.substring(0, 10) + '…' : message.raw_message)}`;
    }
    if (count > messages.length) {
      result += `\n<b>共 ${count} 条消息记录</b>`;
    }
    return result;
  },

  getMessageDocumentId(message: Api.Message) {
    if (message.document) {
      return BigInt(message.document.id.toString());
    }
    if (message.file) {
      const media = Reflect.get(message.file, 'media');
      return BigInt(media.id.toString());
    }
    return null;
  },
};