import { computed, ref } from 'vue'
import { useAuth } from './useAuth'
import { extractErrorCode, useServerErrors } from './useLocaleText'
import { getGlobalDedup } from './useRequestDedup'
import { useLocale } from '~/utils/locale'
import type { PlayTime, Schedule, Song } from '~/types'

export const useSongs = () => {
  const { isAuthenticated, user, getAuthConfig } = useAuth()
  const { songs: songsLocale } = useLocale()
  const { localize: localizeServerError } = useServerErrors()
  const dedup = getGlobalDedup()

  const songs = ref<Song[]>([])
  const publicSchedules = ref<Schedule[]>([])
  const publicSongs = ref<Song[]>([])
  const loading = ref(false)
  const error = ref('')
  const notification = ref({ show: false, message: '', type: '' })
  const playTimes = ref<PlayTime[]>([])
  const playTimeEnabled = ref(false)
  const songCount = ref(0)
  const requestFormLocale = computed(() => songsLocale.value?.requestForm)
  const actionLocale = computed(() => songsLocale.value.actions)

  let songsRequestVersion = 0
  let publicSchedulesRequestVersion = 0

  // 显示通知
  const showNotification = (message: string, type: 'success' | 'error' | 'info' = 'info') => {
    // 使用全局通知
    if (window.$showNotification) {
      window.$showNotification(message, type)
    } else {
      // 备用方案
      notification.value = {
        show: true,
        message,
        type
      }

      // 3秒后自动关闭
      setTimeout(() => {
        notification.value.show = false
      }, 3000)
    }
  }

  // 获取播放时段列表
  const fetchPlayTimes = async () => {
    loading.value = true
    error.value = ''

    try {
      const response = await $fetch('/api/play-times')
      playTimeEnabled.value = response.enabled

      // 确保类型兼容性
      if (response.playTimes && Array.isArray(response.playTimes)) {
        playTimes.value = response.playTimes.map((pt) => ({
          id: pt.id,
          name: pt.name,
          startTime: pt.startTime || undefined,
          endTime: pt.endTime || undefined,
          enabled: pt.enabled,
          description: pt.description || undefined
        }))
      } else {
        playTimes.value = []
      }

      return response
    } catch (err: any) {
      error.value = err.message || '获取播放时段失败'
      return { enabled: false, playTimes: [] }
    } finally {
      loading.value = false
    }
  }

  // 获取歌曲列表
  const fetchSongs = async (silent = false, semester?: string, forceRefresh = false) => {
    const requestVersion = ++songsRequestVersion
    if (!silent) {
      loading.value = true
    }
    error.value = ''

    try {
      const requestUserId = user.value?.id ?? null
      const requestParams = {
        semester: semester || '',
        audience: requestUserId ? `user:${requestUserId}` : 'guest',
        role: user.value?.role || ''
      }
      const request = async () => {
        // 构建URL参数
        const params = new URLSearchParams()
        if (semester) {
          params.append('semester', semester)
        }
        const url = `/api/songs${params.toString() ? '?' + params.toString() : ''}`

        // API请求
        return await $fetch(url, {
          ...getAuthConfig()
        })
      }
      const response = forceRefresh
        ? await request()
        : await dedup.dedupedRequest('songs', request, requestParams)

      if (
        requestVersion !== songsRequestVersion ||
        (user.value?.id ?? null) !== requestUserId ||
        (user.value?.role ?? '') !== (requestParams.role || '')
      )
        return

      // 正确解析API返回的数据结构
      if (response && response.success && response.data && Array.isArray(response.data.songs)) {
        songs.value = response.data.songs as Song[]
      } else {
        songs.value = []
        console.warn('API返回的数据格式不正确:', response)
      }
    } catch (err: any) {
      if (requestVersion === songsRequestVersion) {
        error.value = err.message || '获取歌曲列表失败'
      }
    } finally {
      if (!silent && requestVersion === songsRequestVersion) {
        loading.value = false
      }
    }
  }

  // 静默刷新歌曲列表 - 不显示加载状态
  const refreshSongsSilent = async () => {
    return fetchSongs(true)
  }

  // 从排期数据中提取歌曲信息
  const extractSongsFromSchedules = (schedules: Schedule[]): Song[] => {
    const songsMap = new Map<string, Song>()

    schedules.forEach((schedule) => {
      if (schedule.song) {
        const songId = String(schedule.song.id)
        if (!songsMap.has(songId)) {
          // 将排期中的歌曲信息转换为完整的Song对象
          const completeSong: Song = {
            id: schedule.song.id,
            title: schedule.song.title,
            artist: schedule.song.artist,
            requester: schedule.song.requester,
            requesterGrade: schedule.song.requesterGrade || null,
            requesterClass: schedule.song.requesterClass || null,
            requesterId: 0, // 默认值，公共API不提供这个信息
            voteCount: schedule.song.voteCount,
            played: schedule.song.played || false,
            playedAt: schedule.song.playedAt || null,
            semester: schedule.song.semester || null,
            requestedAt: schedule.song.requestedAt || new Date().toISOString(),
            cover: schedule.song.cover || null,
            musicPlatform: schedule.song.musicPlatform || null,
            musicId: schedule.song.musicId || null,
            durationSeconds: schedule.song.durationSeconds || null,
            usedCardCode: schedule.song.usedCardCode === true,
            hasSubmissionNote: schedule.song.hasSubmissionNote === true,
            submissionNote: schedule.song.submissionNote || null,
            submissionNotePublic: schedule.song.submissionNotePublic === true
          }
          songsMap.set(songId, completeSong)
        }
      }
    })

    return Array.from(songsMap.values())
  }

  // 获取公共排期（无需登录）
  const fetchPublicSchedules = async (silent = false, semester?: string, forceRefresh = false) => {
    const requestVersion = ++publicSchedulesRequestVersion
    if (!silent) {
      loading.value = true
    }
    error.value = ''

    try {
      const requestUserId = user.value?.id ?? null
      const requestParams = {
        semester: semester || '',
        audience: requestUserId ? `user:${requestUserId}` : 'guest',
        role: user.value?.role || ''
      }
      const request = async () => {
        // 构建URL参数
        const params = new URLSearchParams()
        if (semester) {
          params.append('semester', semester)
        }
        const url = `/api/songs/public${params.toString() ? '?' + params.toString() : ''}`

        const response = await $fetch(url, {
          ...getAuthConfig()
        })
        return response
      }
      const data = forceRefresh
        ? await request()
        : await dedup.dedupedRequest('public-schedules', request, requestParams)

      if (
        requestVersion !== publicSchedulesRequestVersion ||
        (user.value?.id ?? null) !== requestUserId ||
        (user.value?.role ?? '') !== (requestParams.role || '')
      )
        return

      // 确保每个排期的歌曲都有played属性，并处理null/undefined转换
      const processedData = data.map((schedule: any) => {
        // 处理歌曲属性
        if (schedule.song && schedule.song.played === undefined) {
          schedule.song.played = false
        }

        // 处理播放时间属性
        let processedPlayTime = null
        if (schedule.playTime) {
          processedPlayTime = {
            ...schedule.playTime,
            startTime: schedule.playTime.startTime || undefined,
            endTime: schedule.playTime.endTime || undefined
          }
        }

        // 返回符合Schedule类型的对象
        return {
          ...schedule,
          playTime: processedPlayTime
        } as Schedule
      })

      publicSchedules.value = processedData

      // 直接从排期数据中提取歌曲信息，避免重复请求
      publicSongs.value = extractSongsFromSchedules(processedData)
    } catch (err: any) {
      if (requestVersion === publicSchedulesRequestVersion) {
        error.value = err.message || '获取排期失败'
      }
    } finally {
      if (!silent && requestVersion === publicSchedulesRequestVersion) {
        loading.value = false
      }
    }
  }

  // 静默刷新公共排期 - 不显示加载状态
  const refreshSchedulesSilent = async () => {
    return fetchPublicSchedules(true)
  }

  // 请求歌曲
  const requestSong = async (songData: {
    title: string
    artist: string
    preferredPlayTimeId?: number | null
    cover?: string | null
    musicPlatform?: string | null
    musicId?: string | null
    submissionNote?: string | null
    submissionNotePublic?: boolean
    cardCode?: string | null
  }) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginRequest, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      // 使用认证配置
      const authConfig = getAuthConfig()

      const data = await $fetch('/api/songs/request', {
        method: 'POST',
        body: songData,
        ...authConfig
      })

      // 绕过去重，从数据库重新校准写入后的列表
      await fetchSongs(true, undefined, true)

      return data
    } catch (err: any) {
      const errorMsg = localizeServerError(err) || '点歌失败'
      // 如果是重复投稿错误，只显示通知而不设置全局错误
      if (errorMsg.includes('已经在列表中') || errorMsg.includes('不能重复投稿')) {
        showNotification(errorMsg, 'info')
      } else {
        error.value = errorMsg
        showNotification(errorMsg, 'error')
      }
      return null
    } finally {
      loading.value = false
    }
  }

  // 投票
  const voteSong = async (songId: number | { id: number; unvote?: boolean }) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginVote, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    // 处理传入的可能是对象的情况
    const actualSongId = typeof songId === 'object' ? songId.id : songId
    const isUnvote = typeof songId === 'object' && songId.unvote === true

    try {
      // 检查是否已经投过票（只在正常投票时检查）
      const targetSong = songs.value.find((s) => s.id === actualSongId)

      if (!isUnvote && targetSong && targetSong.voted) {
        showNotification(actionLocale.value.alreadyVoted, 'info')
        loading.value = false
        return null
      }

      // 使用认证配置
      const authConfig = getAuthConfig()

      try {
        const data = await $fetch('/api/songs/vote', {
          method: 'POST',
          body: {
            songId: actualSongId,
            unvote: isUnvote // 添加取消投票参数
          },
          ...authConfig
        })

        // 立即更新本地歌曲的投票状态
        if (targetSong) {
          if (isUnvote) {
            // 取消投票
            targetSong.voted = false
            targetSong.voteCount = Math.max(0, (targetSong.voteCount || 1) - 1)
            showNotification(actionLocale.value.voteCancelled(targetSong.title), 'success')
          } else {
            // 正常投票
            targetSong.voted = true
            targetSong.voteCount = (targetSong.voteCount || 0) + 1
            showNotification(actionLocale.value.voteSucceeded(targetSong.title), 'success')
          }
        }

        await fetchSongs(true, undefined, true)

        return data
      } catch (fetchErr: any) {
        // 处理API返回的错误
        const errorMsg = fetchErr.data?.message || fetchErr.message || '投票失败'

        // 如果是已投票错误，只显示通知，不抛出异常
        if (errorMsg.includes('已经为这首歌投过票')) {
          showNotification(actionLocale.value.alreadyVoted, 'info')

          // 如果API返回已投票错误，也更新本地状态
          if (targetSong && !targetSong.voted) {
            targetSong.voted = true
          }

          return null
        }

        // 其他错误则抛出
        throw fetchErr
      }
    } catch (err: any) {
      const errorMsg = err.data?.message || err.message || '投票失败'
      error.value = errorMsg
      showNotification(errorMsg, 'error')
      return null
    } finally {
      loading.value = false
    }
  }

  // 撤回歌曲（只能撤回自己的投稿）
  const withdrawSong = async (songId: number) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginWithdraw, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      // 查找歌曲信息用于通知
      const targetSong = songs.value.find((s) => s.id === songId)
      const songTitle = targetSong ? targetSong.title : actionLocale.value.fallbackSongTitle

      // 使用认证配置
      const authConfig = getAuthConfig()

      const data = await $fetch('/api/songs/withdraw', {
        method: 'POST',
        body: { songId },
        ...authConfig
      })

      // 绕过去重，从数据库重新校准写入后的列表
      await fetchSongs(true, undefined, true)

      // 显示成功通知
      let message = ''
      if (data.action === 'leave') {
        message = actionLocale.value.leaveCollaborationSucceeded(songTitle)
      } else if (data.message) {
        // 如果后端返回了特定消息，优先使用（除了撤回投稿的情况，我们要保留带标题的格式）
        message = data.message
      } else {
        message = data.quotaReturned
          ? actionLocale.value.withdrawSucceededQuota(songTitle)
          : actionLocale.value.withdrawSucceeded(songTitle)
      }

      if (data.action !== 'leave') {
        message = data.quotaReturned
          ? actionLocale.value.withdrawSucceededQuota(songTitle)
          : actionLocale.value.withdrawSucceeded(songTitle)
      }

      showNotification(message, 'success')
      return data
    } catch (err: any) {
      const errorMsg = err.data?.message || err.message || '撤回歌曲失败'
      error.value = errorMsg
      showNotification(errorMsg, 'error')
      return null
    } finally {
      loading.value = false
    }
  }

  // 删除歌曲（管理员专用）
  const deleteSong = async (songId: number) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginDelete, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      // 使用认证配置
      const authConfig = getAuthConfig()

      const data = await $fetch('/api/admin/songs/delete', {
        method: 'POST',
        body: { songId },
        ...authConfig
      })

      // 绕过去重，从数据库重新校准写入后的列表
      await fetchSongs(true, undefined, true)

      showNotification(actionLocale.value.deleteSucceeded, 'success')
      return data
    } catch (err: any) {
      const errorMsg = err.data?.message || err.message || '删除歌曲失败'
      error.value = errorMsg
      showNotification(errorMsg, 'error')
      return null
    } finally {
      loading.value = false
    }
  }

  // 标记歌曲为已播放（管理员专用）
  const markPlayed = async (songId: number) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginMarkPlayed, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      // 使用认证配置
      const authConfig = getAuthConfig()

      const data = await $fetch('/api/admin/songs/mark-played', {
        method: 'POST',
        body: { songId },
        ...authConfig
      })

      // 绕过去重，从数据库重新校准写入后的列表
      await fetchSongs(true, undefined, true)

      showNotification(actionLocale.value.markPlayedSucceeded, 'success')
      return data
    } catch (err: any) {
      const errorMsg = err.data?.message || err.message || '标记歌曲失败'
      error.value = errorMsg
      showNotification(errorMsg, 'error')
      return null
    } finally {
      loading.value = false
    }
  }

  // 撤回歌曲已播放状态（管理员专用）
  const unmarkPlayed = async (songId: number) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginUnmarkPlayed, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      // 使用认证配置
      const authConfig = getAuthConfig()

      const data = await $fetch('/api/admin/songs/mark-played', {
        method: 'POST',
        body: { songId, unmark: true },
        ...authConfig
      })

      // 绕过去重，从数据库重新校准写入后的列表
      await fetchSongs(true, undefined, true)

      showNotification(actionLocale.value.unmarkPlayedSucceeded, 'success')
      return data
    } catch (err: any) {
      const errorMsg = err.data?.message || err.message || '撤回歌曲已播放状态失败'
      error.value = errorMsg
      showNotification(errorMsg, 'error')
      return null
    } finally {
      loading.value = false
    }
  }

  // 申请重播
  const requestReplay = async (
    songId: number,
    options: {
      preferredPlayTimeId?: number | null
      submissionNote?: string | null
      submissionNotePublic?: boolean
    } = {}
  ) => {
    if (!isAuthenticated.value) {
      showNotification(actionLocale.value.loginRequestReplay, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      const authConfig = getAuthConfig()
      const data = await $fetch('/api/songs/replay', {
        method: 'POST',
        body: { songId, ...options },
        ...authConfig
      })

      // 更新本地数据状态
      const songIndex = songs.value.findIndex((s) => s.id === songId)
      if (songIndex !== -1) {
        songs.value[songIndex].replayRequested = true
      }

      await fetchSongs(true, undefined, true)

      showNotification(actionLocale.value.replaySucceeded, 'success')
      return data
    } catch (err: any) {
      // 按错误码本地化展示，重复申请降级为提示
      if (extractErrorCode(err) === 'SONG_REPLAY_ALREADY_REQUESTED') {
        showNotification(actionLocale.value.replayAlreadyRequested, 'info')
      } else {
        showNotification(localizeServerError(err) || '申请重播失败', 'error')
      }
      return null
    } finally {
      loading.value = false
    }
  }

  /**
   * 撤回重播申请
   * @param songId 歌曲ID
   */
  const withdrawReplay = async (songId: number) => {
    const { user } = useAuth()
    if (!user.value) {
      showNotification(actionLocale.value.loginCancelReplay, 'error')
      return null
    }

    loading.value = true
    error.value = ''

    try {
      const authConfig = getAuthConfig()
      const data = await $fetch('/api/songs/replay', {
        method: 'DELETE',
        body: { songId },
        ...authConfig
      })

      // 更新本地数据状态
      const songIndex = songs.value.findIndex((s) => s.id === songId)
      if (songIndex !== -1) {
        songs.value[songIndex].replayRequested = false
      }

      await fetchSongs(true, undefined, true)

      showNotification(actionLocale.value.replayCancelled, 'success')
      return data
    } catch (err: any) {
      showNotification(localizeServerError(err) || '取消重播申请失败', 'error')
      return null
    } finally {
      loading.value = false
    }
  }

  // 按热度排序的歌曲
  const songsByPopularity = computed(() => {
    return [...songs.value].sort((a, b) => b.voteCount - a.voteCount)
  })

  // 按创建时间排序的歌曲
  const songsByDate = computed(() => {
    return [...songs.value].sort(
      (a, b) => new Date(b.createdAt).getTime() - new Date(a.createdAt).getTime()
    )
  })

  // 已播放的歌曲
  const playedSongs = computed(() => {
    return songs.value.filter((song) => song.played)
  })

  // 未播放的歌曲
  const unplayedSongs = computed(() => {
    return songs.value.filter((song) => !song.played)
  })

  // 我的投稿歌曲
  const mySongs = computed(() => {
    if (!user.value) return []
    return songs.value.filter((song) => song.requesterId === user.value?.id)
  })

  // 我的重播申请歌曲
  const myReplaySongs = computed(() => {
    if (!user.value) return []
    return songs.value.filter((song) => song.replayRequested)
  })

  // 所有可见的歌曲（登录用户看到的 + 公共歌曲）
  const visibleSongs = computed(() => {
    return isAuthenticated.value ? songs.value : publicSongs.value
  })

  const clearPrivateSongs = () => {
    songsRequestVersion++
    songs.value = []
  }

  const clearPublicSongs = () => {
    publicSchedulesRequestVersion++
    publicSongs.value = []
    publicSchedules.value = []
  }

  // 根据播放时间段过滤歌曲排期
  const filterSchedulesByPlayTime = (schedules: Schedule[], playTimeId: number | null) => {
    if (playTimeId === null) {
      return schedules.filter((s) => s.playTimeId === null)
    }
    return schedules.filter((s) => s.playTimeId === playTimeId)
  }

  // 获取播放时间名称
  const getPlayTimeName = (playTimeId: number | null) => {
    if (playTimeId === null) {
      return '未指定时段'
    }

    const foundTime = playTimes.value.find((pt) => pt.id === playTimeId)
    return foundTime ? foundTime.name : '未知时段'
  }

  // 格式化播放时间显示
  const formatPlayTimeDisplay = (playTime: PlayTime | null) => {
    if (!playTime) {
      return '全天'
    }

    let displayText = playTime.name

    // 如果有开始和结束时间，添加时间信息
    if (playTime.startTime && playTime.endTime) {
      displayText += ` (${playTime.startTime}-${playTime.endTime})`
    }
    // 如果只有开始时间
    else if (playTime.startTime) {
      displayText += ` (${playTime.startTime}起)`
    }
    // 如果只有结束时间
    else if (playTime.endTime) {
      displayText += ` (至${playTime.endTime})`
    }

    return displayText
  }

  // 获取歌曲总数
  const fetchSongCount = async (forceRefresh = false) => {
    try {
      const request = async () => {
        const response = await $fetch('/api/songs/count')
        return response
      }
      const response = forceRefresh
        ? await request()
        : await dedup.dedupedRequest('song-count', request)

      // 正确解析API返回的数据结构
      if (response && typeof response.count === 'number') {
        songCount.value = response.count
        return response.count
      } else {
        console.warn('歌曲总数API返回的数据格式不正确:', response)
        songCount.value = 0
        return 0
      }
    } catch (err: any) {
      console.error('获取歌曲总数失败:', err)
      return 0
    }
  }

  // 初始化加载
  const initialize = async () => {
    await fetchPlayTimes()
    if (isAuthenticated.value) {
      await fetchSongs()
    } else {
      await fetchPublicSchedules()
    }
  }

  return {
    songs,
    publicSongs,
    publicSchedules,
    visibleSongs,
    songCount,
    loading,
    error,
    notification,
    playTimes,
    playTimeEnabled,
    showNotification,
    fetchSongs,
    fetchPublicSchedules,
    fetchPlayTimes,
    fetchSongCount,
    clearPrivateSongs,
    clearPublicSongs,
    refreshSongsSilent,
    refreshSchedulesSilent,
    requestSong,
    voteSong,
    withdrawSong,
    deleteSong,
    markPlayed,
    unmarkPlayed,
    requestReplay,
    withdrawReplay,
    filterSchedulesByPlayTime,
    getPlayTimeName,
    formatPlayTimeDisplay,
    extractSongsFromSchedules,
    initialize,
    songsByPopularity,
    songsByDate,
    playedSongs,
    unplayedSongs,
    mySongs,
    myReplaySongs
  }
}