import fp from 'fastify-plugin';
import cron from 'node-cron';
import staticBots from '../config/bots.js';
import { syncAllSchedules } from '../services/meilisearch/index.js';
import { nowKST } from '../utils/date.js';

const REDIS_PREFIX = 'bot:status:';
const TIMEZONE = 'Asia/Seoul';

async function schedulerPlugin(fastify, opts) {
  const tasks = new Map();
  let cachedBots = null;

  /**
   * DB에서 YouTube 봇 목록 조회
   */
  async function getYouTubeBotsFromDB() {
    const [rows] = await fastify.db.query(
      'SELECT * FROM bot_youtube WHERE enabled = 1'
    );
    return rows.map(row => ({
      id: `youtube-${row.id}`,  // DB ID를 문자열 형식으로 변환
      dbId: row.id,
      type: 'youtube',
      channelId: row.channel_id,
      channelHandle: row.channel_handle,
      channelName: row.channel_name,
      bannerUrl: row.banner_url,
      cron: `*/${row.cron_interval} * * * *`,
      enabled: row.enabled === 1,
      titleFilters: row.title_filters
        ? (typeof row.title_filters === 'string'
            ? JSON.parse(row.title_filters)
            : row.title_filters)
        : [],
      defaultMemberIds: row.default_member_ids
        ? (typeof row.default_member_ids === 'string'
            ? JSON.parse(row.default_member_ids)
            : row.default_member_ids)
        : [],
      extractMembersFromDesc: row.extract_members_from_desc === 1,
      autoScheduleNext: row.auto_schedule_config
        ? (typeof row.auto_schedule_config === 'string'
            ? JSON.parse(row.auto_schedule_config)
            : row.auto_schedule_config)
        : null,
    }));
  }

  /**
   * DB에서 X 봇 목록 조회
   */
  async function getXBotsFromDB() {
    const [rows] = await fastify.db.query(
      'SELECT * FROM bot_x WHERE enabled = 1'
    );
    return rows.map(row => ({
      id: `x-${row.id}`,
      dbId: row.id,
      type: 'x',
      username: row.username,
      displayName: row.display_name,
      avatarUrl: row.avatar_url,
      nitterUrl: process.env.NITTER_URL || 'http://nitter:8080',
      cron: `*/${row.cron_interval} * * * *`,
      enabled: row.enabled === 1,
      textFilters: row.text_filters
        ? (typeof row.text_filters === 'string'
            ? JSON.parse(row.text_filters)
            : row.text_filters)
        : [],
    }));
  }

  /**
   * 모든 봇 목록 가져오기 (정적 + DB)
   */
  async function getAllBots(forceRefresh = false) {
    if (cachedBots && !forceRefresh) {
      return cachedBots;
    }
    const youtubeBots = await getYouTubeBotsFromDB();
    const xBots = await getXBotsFromDB();
    cachedBots = [...staticBots, ...youtubeBots, ...xBots];
    return cachedBots;
  }

  /**
   * 봇 ID로 봇 찾기
   */
  async function findBot(botId) {
    const allBots = await getAllBots();
    return allBots.find(b => b.id === botId);
  }

  /**
   * 봇 상태 Redis에 저장
   */
  async function updateStatus(botId, status) {
    const current = await getStatus(botId);
    const updated = { ...current, ...status, updatedAt: nowKST() };
    await fastify.redis.set(`${REDIS_PREFIX}${botId}`, JSON.stringify(updated));
    return updated;
  }

  /**
   * 봇 상태 Redis에서 조회
   */
  async function getStatus(botId) {
    const data = await fastify.redis.get(`${REDIS_PREFIX}${botId}`);
    if (data) {
      return JSON.parse(data);
    }
    return {
      status: 'stopped',
      lastCheckAt: null,
      lastAddedCount: 0,
      totalAdded: 0,
      lastSyncDuration: null,
      errorMessage: null,
    };
  }

  /**
   * 봇 동기화 함수 가져오기
   */
  function getSyncFunction(bot) {
    if (bot.type === 'youtube') {
      return fastify.youtubeBot.syncNewVideos;
    } else if (bot.type === 'x') {
      return fastify.xBot.syncNewTweets;
    } else if (bot.type === 'meilisearch') {
      return async () => {
        const count = await syncAllSchedules(fastify.meilisearch, fastify.db);
        return { addedCount: count, total: count };
      };
    }
    return null;
  }

  /**
   * 동기화 결과 처리
   */
  async function handleSyncResult(botId, result, options = {}) {
    const { setRunningStatus = false } = options;
    const status = await getStatus(botId);
    const updateData = {
      lastCheckAt: nowKST(),
      totalAdded: (status.totalAdded || 0) + result.addedCount,
    };
    if (setRunningStatus) {
      updateData.status = 'running';
      updateData.errorMessage = null;
    }
    if (result.addedCount > 0) {
      updateData.lastAddedCount = result.addedCount;
    }
    await updateStatus(botId, updateData);
    return result.addedCount;
  }

  /**
   * 봇 시작
   */
  async function startBot(botId) {
    const bot = await findBot(botId);
    if (!bot) {
      throw new Error(`봇을 찾을 수 없습니다: ${botId}`);
    }

    // 기존 태스크가 있으면 정지
    if (tasks.has(botId)) {
      tasks.get(botId).stop();
      tasks.delete(botId);
    }

    const syncFn = getSyncFunction(bot);
    if (!syncFn) {
      throw new Error(`지원하지 않는 봇 타입: ${bot.type}`);
    }

    // cron 태스크 등록 (한국 시간 기준)
    const task = cron.schedule(bot.cron, async () => {
      fastify.log.info(`[${botId}] 동기화 시작`);
      try {
        const result = await syncFn(bot);
        const addedCount = await handleSyncResult(botId, result, { setRunningStatus: true });
        fastify.log.info(`[${botId}] 동기화 완료: ${addedCount}개 추가`);
      } catch (err) {
        await updateStatus(botId, {
          status: 'error',
          lastCheckAt: nowKST(),
          errorMessage: err.message,
        });
        fastify.log.error(`[${botId}] 동기화 오류: ${err.message}`);
      }
    }, { timezone: TIMEZONE });

    tasks.set(botId, task);
    await updateStatus(botId, { status: 'running' });
    fastify.log.info(`[${botId}] 스케줄 시작 (cron: ${bot.cron})`);

    // 즉시 1회 실행 (meilisearch는 스케줄 시간에만 실행)
    if (bot.type !== 'meilisearch') {
      try {
        const result = await syncFn(bot);
        const addedCount = await handleSyncResult(botId, result);
        fastify.log.info(`[${botId}] 초기 동기화 완료: ${addedCount}개 추가`);
      } catch (err) {
        fastify.log.error(`[${botId}] 초기 동기화 오류: ${err.message}`);
      }
    }
  }

  /**
   * 봇 정지
   */
  async function stopBot(botId) {
    if (tasks.has(botId)) {
      tasks.get(botId).stop();
      tasks.delete(botId);
    }
    await updateStatus(botId, { status: 'stopped' });
    fastify.log.info(`[${botId}] 스케줄 정지`);
  }

  /**
   * 모든 활성 봇 시작
   */
  async function startAll() {
    const allBots = await getAllBots(true); // DB에서 새로 로드
    for (const bot of allBots) {
      if (bot.enabled) {
        try {
          await startBot(bot.id);
        } catch (err) {
          fastify.log.error(`[${bot.id}] 시작 실패: ${err.message}`);
        }
      }
    }
  }

  /**
   * 모든 봇 정지
   */
  async function stopAll() {
    for (const [botId, task] of tasks) {
      task.stop();
      await updateStatus(botId, { status: 'stopped' });
    }
    tasks.clear();
  }

  /**
   * 봇 캐시 갱신 (봇 추가/수정/삭제 시 호출)
   */
  function invalidateCache() {
    cachedBots = null;
  }

  // 데코레이터 등록
  fastify.decorate('scheduler', {
    startBot,
    stopBot,
    startAll,
    stopAll,
    getStatus,
    getBots: (forceRefresh = false) => getAllBots(forceRefresh),
    invalidateCache,
  });

  // 앱 종료 시 모든 봇 정지
  fastify.addHook('onClose', async () => {
    await stopAll();
    fastify.log.info('모든 봇 스케줄 정지');
  });
}

export default fp(schedulerPlugin, {
  name: 'scheduler',
  dependencies: ['db', 'redis', 'meilisearch', 'youtubeBot', 'xBot'],
});