const cloud = require('wx-server-sdk')
cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV })
const db = cloud.database()
const _ = db.command
const RESULT_LIMIT = 20

function escapeRegExp(s) {
  return String(s).replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
}

exports.main = async (event, context) => {
  const { OPENID } = cloud.getWXContext()
  const keyword = String((event && event.keyword) || '').trim()
  if (!keyword) return { code: 0, data: [] }

  try {
    const re = db.RegExp({ regexp: escapeRegExp(keyword), options: 'i' })
    const postsRes = await db.collection('posts')
      .where(_.or([{ content: re }, { hashtags: keyword }]))
      .orderBy('createdAt', 'desc')
      .limit(RESULT_LIMIT)
      .get()

    const posts = postsRes.data
    if (posts.length === 0) return { code: 0, data: [] }

    const authorIds = [...new Set(posts.map(p => p.authorId))]
    const authorsRes = await db.collection('users')
      .where({ openid: _.in(authorIds) })
      .field({ nickName: true, avatarUrl: true, openid: true, pets: true, location: true })
      .get()
    const authorMap = {}
    authorsRes.data.forEach(u => { authorMap[u.openid] = u })

    const postIds = posts.map(p => p._id)
    const likesRes = await db.collection('likes')
      .where({ userId: OPENID, postId: _.in(postIds) })
      .field({ postId: true })
      .get()
    const likedSet = new Set(likesRes.data.map(l => l.postId))

    const enriched = posts.map(p => ({
      ...p,
      author: authorMap[p.authorId] || null,
      isLiked: likedSet.has(p._id),
    }))

    return { code: 0, data: enriched }
  } catch (e) {
    return { code: -1, message: e.message }
  }
}