/**
 * Phase: videos — 视频生成（VEO / Grok / Kling）
 *
 * 图生视频，批量提交，生成后自动上传 OSS
 * 支持 task ID 恢复：中断后重跑时优先恢复已有任务
 */

const path = require('path')
const { saveManifest, ensureDir, log, getManifestDir } = require('./pipeline-utils')

function isQuotaError(msg) {
  if (!msg) return false
  const s = msg.toLowerCase()
  return /quota|limit|exceed|insufficient|余额|额度|超限|rate.?limit|too.?many/.test(s)
}

function applyPollResult(item, val, dir) {
  if (val.ok && val.result?.file) {
    item.video = path.relative(dir, val.result.file).replace(/\\/g, '/')
    item.videoDuration = val.result.duration
    item.status = 'done'
    delete item.videoTaskId
  } else if (val.item) {
    if (val.isTaskFailure) {
      item.status = 'failed'
      item.error = val.error || '视频生成未返回文件'
      delete item.videoTaskId
    } else {
      log('videos', `  item ${item.id} 生成超时（保留 taskId 待恢复）: ${val.error}`)
      item.status = 'pending'
    }
  }
}

async function phaseVideos(manifest, manifestPath, options) {
  const dir = getManifestDir(manifestPath)
  const videosDir = path.join(dir, 'videos')
  ensureDir(videosDir)

  const accountConfig = options.accountConfig || {}
  const videoModel = manifest.videoModel || accountConfig.videoModel || 'veo3-fast-frames'

  const videoCandidates = manifest.items.filter(it => {
    if (it.confirmed === false) return false
    if (!it.url || !it.videoPrompt) return false
    // 已有视频（本地文件或远程 URL）且状态为 done → 跳过，避免重复生成
    if (it.status === 'done' && (it.video || it.videoUrl)) return false
    return ['done', 'pending', 'failed'].includes(it.status)
  })

  if (videoCandidates.length === 0) {
    console.log("\n⚠️  [videos] 没有符合条件的 item 进入视频生成阶段")
    console.log("   manifest 中共有", manifest.items.length, "个 item，逐一诊断:")
    for (const it of manifest.items) {
      const reasons = []
      if (it.confirmed === false) reasons.push("confirmed=false")
      if (!it.url) reasons.push("缺少 url（图片未上传）")
      if (!it.videoPrompt) reasons.push("缺少 videoPrompt")
      if (it.status === 'done' && (it.video || it.videoUrl)) {
        reasons.push("视频已生成，已跳过")
      } else if (!["done","pending","failed"].includes(it.status)) {
        reasons.push("status=" + (it.status || "undefined") + "（不在 done/pending/failed 中）")
      }
      console.log("   - item", it.id || manifest.items.indexOf(it), ":", reasons.length > 0 ? reasons.join(", ") : "已满足全部条件（不应在此）")
    }
    console.log("\n   修复命令:")
    console.log("   node .claude/skills/video-from-script/scripts/pipeline.js confirm --manifest", manifestPath, "--all")
    console.log()
  }

  const items = []
  for (const it of videoCandidates) {
    // 磁盘兜底：本地视频文件已存在则恢复引用并跳过
    if (!it.video && it.id) {
      const fs = require('fs')
      const existingVideos = fs.readdirSync(videosDir).filter(f =>
        f.includes('_item' + it.id + '_') || f.includes('_item' + it.id + '.')
      )
      if (existingVideos.length > 0) {
        it.video = 'videos/' + existingVideos[existingVideos.length - 1]
        it.status = 'done'
        delete it.videoTaskId
        log('videos', `  item ${it.id} 发现已有视频文件 ${it.video}，跳过生成`)
        continue
      }
    }
    if (it.video || it.videoUrl) {
      if (it.status === 'done') continue
      delete it.video
      delete it.videoUrl
      delete it.videoDuration
    }
    items.push(it)
  }
  if (items.length === 0) { log('videos', '无待处理 item，跳过'); return }

  let Api, pollFn
  const modelLower = videoModel.toLowerCase()
  if (modelLower.includes('grok')) {
    const gen = require('../grok-video-generator')
    Api = gen.GrokApi; pollFn = gen.pollWithRetry
  } else if (modelLower.includes('kling')) {
    const gen = require('../kling-video-generator')
    Api = gen.KlingApi; pollFn = gen.pollWithRetry
  } else {
    const gen = require('../veo-video-generator')
    Api = gen.VeoApi; pollFn = gen.pollWithRetry
  }

  const ratio = manifest.format || '9:16'
  const pollOpts = (item) => ({
    outputDir: videosDir, aspectRatio: ratio,
    imageUrl: item.url, lastFrameUrl: item.lastFrameUrl || '',
  })

  log('videos', `共 ${items.length} 个, 模型: ${videoModel}`)

  // Phase 1: 恢复已有任务（有 videoTaskId 的 item）
  const recovered = []
  const needSubmit = []

  for (const item of items) {
    if (item.videoTaskId) {
      recovered.push(item)
    } else {
      needSubmit.push(item)
    }
  }

  if (recovered.length > 0) {
    log('videos', `尝试恢复 ${recovered.length} 个中断任务...`)
    await Promise.allSettled(
      recovered.map(async (item) => {
        try {
          log('videos', `  恢复 item ${item.id}: ${item.videoTaskId}`)
          const result = await pollFn(item.videoTaskId, item.videoPrompt, pollOpts(item))
          if (result.file) {
            item.video = path.relative(dir, result.file).replace(/\\/g, '/')
            item.videoDuration = result.duration
            item.status = 'done'
            delete item.videoTaskId
            log('videos', `  item ${item.id} 恢复成功`)
          }
        } catch (err) {
          if (err.isTaskFailure === true) {
            log('videos', `  item ${item.id} 恢复失败（任务失败）: ${err.message}，将重新提交`)
            delete item.videoTaskId
            needSubmit.push(item)
          } else {
            log('videos', `  item ${item.id} 恢复超时（保留 taskId 下次重试）: ${err.message}`)
            item.status = 'pending'
          }
        }
      })
    )
    saveManifest(manifestPath, manifest)
  }

  if (needSubmit.length === 0) { log('videos', '全部通过恢复完成'); return }

  // Phase 2+3: 分批提交+轮询（严格并发 ≤ 5，等一批完成再提交下一批）
  const concurrency = 5
  log('videos', `提交 ${needSubmit.length} 个新任务（并发: ${concurrency}）...`)

  for (let i = 0; i < needSubmit.length; i += concurrency) {
    const batch = needSubmit.slice(i, i + concurrency).filter(item => !item.videoTaskId)
    if (batch.length === 0) continue

    // 提交本批
    const submitResults = await Promise.allSettled(
      batch.map(async (item) => {
        const extraOpts = item.lastFrameUrl
          ? { aspectRatio: ratio, lastFrameUrl: item.lastFrameUrl, mode: 'pro' }
          : { aspectRatio: ratio }
        try {
          const taskId = await Api.create(item.url, item.videoPrompt, extraOpts)
          return { item, taskId, error: null }
        } catch (err) {
          return { item, taskId: null, error: err.message }
        }
      })
    )

    const submitted = []
    let hitQuota = false
    for (const r of submitResults) {
      const val = r.status === 'fulfilled' ? r.value : { item: null, taskId: null, error: r.reason }
      submitted.push(val)
      if (val.item && val.taskId) {
        val.item.videoTaskId = val.taskId
      } else if (val.item && !val.taskId) {
        val.item.status = 'failed'
        val.item.error = val.error || '提交失败'
        if (isQuotaError(val.error)) hitQuota = true
      }
    }
    saveManifest(manifestPath, manifest)

    if (hitQuota) {
      log('videos', `  ⚠️ 额度不足，停止提交（跳过剩余 ${needSubmit.length - i - batch.length} 个任务）`)
      break
    }

    // 轮询本批
    const pending = submitted.filter(s => s.taskId)
    if (pending.length === 0) continue

    const end = Math.min(i + concurrency, needSubmit.length)
    log('videos', `  [${i + 1}-${end}/${needSubmit.length}] 等待 ${pending.length} 个视频生成...`)

    const pollResults = await Promise.allSettled(
      pending.map(async ({ item, taskId }) => {
        try {
          const result = await pollFn(taskId, item.videoPrompt, pollOpts(item))
          return { item, result, ok: true }
        } catch (err) {
          return { item, error: err.message, ok: false, isTaskFailure: err.isTaskFailure === true }
        }
      })
    )

    for (const r of pollResults) {
      const val = r.status === 'fulfilled'
        ? r.value
        : { ok: false, error: r.reason?.message || String(r.reason), isTaskFailure: r.reason?.isTaskFailure === true }
      applyPollResult(val.item || {}, val, dir)
    }
    saveManifest(manifestPath, manifest)
  }

  // 上传视频到 OSS
  const { uploadFile } = require('../oss-upload')
  const videoItems = manifest.items.filter(it => it.video && !it.videoUrl)
  if (videoItems.length > 0) {
    log('videos', `上传 ${videoItems.length} 个视频到 OSS...`)
    for (const item of videoItems) {
      const videoPath = path.resolve(dir, item.video)
      try {
        const { url } = await uploadFile(videoPath)
        item.videoUrl = url
        log('videos', `  ${item.video} → OK`)
      } catch (err) {
        log('videos', `  ${item.video} 上传失败: ${err.message}`)
      }
    }
    saveManifest(manifestPath, manifest)
  }
}

module.exports = { phaseVideos }