/* eslint-disable @typescript-eslint/no-unsafe-return */
/* eslint-disable @typescript-eslint/member-delimiter-style */
/* eslint-disable prefer-arrow/prefer-arrow-functions */
import * as fs from 'fs';
import * as path from 'path';

import { relativeDate } from './datetime';
import { getLogger } from './loggers';
import {
  sendAllStories, sendStory, sendTimeline, ScreenNameNormalizer as normalizer,
  linkBuilder, parseLink
} from './twitter';

const logger = getLogger('command');

function parseCmd(message: string): {
  cmd: string;
  args: string[];
} {
  message = message.trim();
  message = message.replace('\\\\', '\\0x5c');
  message = message.replace('\\\"', '\\0x22');
  message = message.replace('\\\'', '\\0x27');
  const strs = message.match(/'[\s\S]*?'|(?:\S+=)?"[\s\S]*?"|\S+/mg);
  const cmd = strs?.length ? strs[0].length ? strs[0].substring(0, 1) === '/' ? strs[0].substring(1) : '' : '' : '';
  const args = (strs ?? []).slice(1).map(arg => {
    arg = arg.replace(/^(\S+=)?["']+(?!.*=)|["']+$/g, '$1');
    arg = arg.replace('\\0x27', '\\\'');
    arg = arg.replace('\\0x22', '\\\"');
    arg = arg.replace('\\0x5c', '\\\\');
    return arg;
  });
  return {
    cmd,
    args,
  };
}

function linkFinder(userName: string, chat: IChat, lock: ILock): [string, number] {
  const normalizedLink = linkBuilder({userName});
  const link = Object.keys(lock.threads).find(realLink =>
    normalizedLink === realLink.replace(/\/@/, '/').toLowerCase()
  );
  if (!link) return [null, -1];
  const index = lock.threads[link].subscribers.findIndex(({chatID, chatType}) =>
    chat.chatID === chatID && chat.chatType === chatType
  );
  return [link, index];
}

function sub(chat: IChat, args: string[], reply: (msg: string) => any,
  lock: ILock, lockfile: string
): void {
  if (chat.chatType === ChatType.Temp) {
    return reply('请先添加机器人为好友。');
  }
  if (args.length === 0) {
    return reply('找不到要订阅 Instagram 限时动态的链接。');
  }
  const matched = parseLink(args[0]);
  if (!matched) {
    return reply(`订阅链接格式错误：
示例：
https://www.instagram.com/tomoyo_kurosawa_/`);
  }
  const subscribeTo = (link: string, config: {id?: number, msg?: string} = {}) => {
    const {id, msg = `已为此聊天订阅 ${link} 的 Instagram 限时动态`} = config;
    if (id) {
      lock.feed.push(link);
      lock.threads[link] = {
        id,
        offset: '0',
        subscribers: [],
        updatedAt: '',
      };
    }
    lock.threads[link].subscribers.push(chat);
    logger.warn(`chat ${JSON.stringify(chat)} has subscribed ${link}`);
    fs.writeFileSync(path.resolve(lockfile), JSON.stringify(lock));
    reply(msg);
  };
  const tryFindSub = (userName: string) => {
    const [realLink, index] = linkFinder(userName, chat, lock);
    if (index > -1) { reply('此聊天已订阅此链接的 Instagram 限时动态。'); return true; }
    if (realLink) { subscribeTo(realLink); return true; }
    return false;
  };
  const newSub = (userName: string) => {
    const link = linkBuilder(matched);
    subscribeTo(link, {id: Number(userName.split(':')[1])});
  };
  if (!tryFindSub(matched.userName)) {
    normalizer.normalizeLive(matched.userName).then(userName => {
      if (!userName) return reply(`找不到用户 ${matched.userName.replace(/^@?(.*)$/, '@$1')}。`);
      else newSub(userName);
    });
  }
}

function unsubAll(chat: IChat, args: string[], reply: (msg: string) => any,
  lock: ILock, lockfile: string
): void {
  if (chat.chatType === ChatType.Temp) {
    return reply('请先添加机器人为好友。');
  }
  Object.entries(lock.threads).forEach(([link, {subscribers}]) => {
    const index = subscribers.indexOf(chat);
    if (index === -1) return;
    subscribers.splice(index, 1);
    fs.writeFileSync(path.resolve(lockfile), JSON.stringify(lock));
    logger.warn(`chat ${JSON.stringify(chat)} has unsubscribed ${link}`);
  });
  return reply(`已为此聊天退订所有 Instagram 限时动态链接。`);
}

function unsub(chat: IChat, args: string[], reply: (msg: string) => any,
  lock: ILock, lockfile: string
): void {
  if (chat.chatType === ChatType.Temp) {
    return reply('请先添加机器人为好友。');
  }
  if (args.length === 0) {
    return reply('找不到要退订 Instagram 限时动态的链接。');
  }
  const match = parseLink(args[0])?.userName;
  if (!match) {
    return reply('链接格式有误。');
  }
  const [link, index] = linkFinder(match, chat, lock);
  if (index === -1) return list(chat, args, msg => reply('您没有订阅此链接的 Instagram 限时动态。\n' + msg), lock);
  else {
    lock.threads[link].subscribers.splice(index, 1);
    fs.writeFileSync(path.resolve(lockfile), JSON.stringify(lock));
    logger.warn(`chat ${JSON.stringify(chat)} has unsubscribed ${link}`);
    return reply(`已为此聊天退订 ${link} 的 Instagram 限时动态`);
  }
}

function list(chat: IChat, _: string[], reply: (msg: string) => any, lock: ILock): void {
  if (chat.chatType === ChatType.Temp) {
    return reply('请先添加机器人为好友。');
  }
  const links = [];
  Object.keys(lock.threads).forEach(key => {
    if (lock.threads[key].subscribers.find(({chatID, chatType}) => 
      chat.chatID === chatID && chat.chatType === chatType
    )) links.push(`${key} ${relativeDate(lock.threads[key].updatedAt)}`);
  });
  return reply('此聊天中订阅的 Instagram 限时动态动态链接：\n' + links.join('\n'));
}

function view(chat: IChat, args: string[], reply: (msg: string) => any): void {
  const promptOnError = <T>(func: (...args: T[]) => void) => (...args: T[]): void => {
    try {
      func(...args);
    } catch (e) {
      reply('机器人尚未加载完毕，请稍后重试。');
    }
  }
  if (args.length === 0) {
    return reply('找不到要查看 Instagram 限时动态的链接。');
  }
  const match = parseLink(args[0]);
  if (!match?.userName) {
    return reply('链接格式有误。');
  }
  if (match?.storyId) {
    return promptOnError(sendStory)(match.userName, match.storyId, chat);
  }
  const conf: {
    skip?: number,
    count?: number,
  } = {};
  const confZH: Record<keyof typeof conf, string> = {
    count: '最大查看数量',
    skip: '跳过数量',
  };
  for (const arg of args.slice(1)) {
    const optMatch = /^(count|skip)=(.*)/.exec(arg);
    if (!optMatch) return reply(`未定义的查看参数：${arg}。`);
    const optKey = optMatch[1] as keyof typeof confZH;
    if (optMatch.length === 1 || !/^-?\d*$/.test(optMatch[2])) return reply(`${confZH[optKey]}参数应为数值。`);
    if (optMatch[2] === '') return reply(`${confZH[optKey]}参数值不可为空。`);
    conf[optKey] = Number(optMatch[2]);
  }
  promptOnError(sendAllStories)(match.userName, chat, conf.skip, conf.count);
}

function query(chat: IChat, args: string[], reply: (msg: string) => any): void {
  if (args.length === 0) {
    return reply('找不到要查询 Instagram 限时动态的用户。');
  }
  const match = parseLink(args[0])?.userName;
  if (!match) {
    return reply('链接格式有误。');
  }
  try {
    sendTimeline(match, chat);
  } catch (e) {
    logger.error(`error querying timeline, error: ${e}`);
    reply('机器人尚未加载完毕，请稍后重试。');
  }
}

export { parseCmd, sub, list, unsub, unsubAll, view, query };