/**
 * Phase: images — 图片生成
 *
 * 支持 Gemini / MJ / Kling 三种模型，含首尾帧模式
 */

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

async function phaseImages(manifest, manifestPath, options) {
  const dir = getManifestDir(manifestPath)
  const imagesDir = path.join(dir, 'images')
  ensureDir(imagesDir)

  const items = manifest.items.filter(it =>
    (!it.status || it.status === 'pending' || it.status === 'generating') && it.imagePrompt
  )
  if (items.length === 0) { log('images', '无待处理 item，跳过'); return }

  const accountConfig = options.accountConfig || {}
  let model = options.imageModel || manifest.imageModel || accountConfig.imageModel || 'gemini'
  const ratio = manifest.format || accountConfig.defaultFormat || '9:16'

  // 首尾帧模式：MJ 降级为 Gemini（MJ 出4张候选图无法一一对应首尾帧）
  if (model === 'mj' && manifest.mode === 'framePair') {
    log('images', '首尾帧模式不支持 MJ，自动降级为 Gemini')
    model = 'gemini'
  }
  const refs = getReferences(manifest, accountConfig)

  log('images', `共 ${items.length} 张, 模型: ${model}, 画幅: ${ratio}, 参考图: ${refs.localPaths.length}本地/${refs.urls.length}URL`)

  for (let i = 0; i < items.length; i++) {
    const item = items[i]
    const idx = i + 1
    try {
      item.status = 'generating'
      saveManifest(manifestPath, manifest)

      let result
      if (model === 'gemini') {
        const { generate: geminiGen, edit: geminiEdit } = require('../gemini-image-generator')
        if (refs.localPaths.length > 0) {
          log('images', `[${idx}/${items.length}] Gemini 图生图: ${item.imagePrompt.substring(0, 60)}...`)
          result = await geminiEdit(item.imagePrompt, refs.localPaths, {
            outputDir: imagesDir,
            aspectRatio: ratio,
          })
        } else {
          log('images', `[${idx}/${items.length}] Gemini 文生图: ${item.imagePrompt.substring(0, 60)}...`)
          result = await geminiGen(item.imagePrompt, {
            outputDir: imagesDir,
            aspectRatio: ratio,
          })
        }
        if (result.savedFiles && result.savedFiles.length > 0) {
          item.file = renameGeneratedFile(
            path.relative(dir, result.savedFiles[0]).replace(/\\/g, '/'),
            dir, idx, item.narration || item.shotDesc, ''
          )
        }
      } else if (model === 'mj') {
        const { generate: mjGen } = require('../mj-image-generator')
        const mjOpts = { outputDir: imagesDir, aspectRatio: ratio, split: true }
        if (refs.urls.length > 0) {
          mjOpts.referenceImages = refs.urls
          mjOpts.styleWeight = 200
        }
        log('images', `[${idx}/${items.length}] MJ 生图: ${item.imagePrompt.substring(0, 60)}...`)
        result = await mjGen(item.imagePrompt, mjOpts)
        if (result.files && result.files.length > 0) {
          item.candidates = result.files.map((f, ci) =>
            renameGeneratedFile(
              path.relative(dir, f).replace(/\\/g, '/'),
              dir, idx, item.narration || item.shotDesc, `cand${ci + 1}`
            )
          )
          item.file = item.candidates[0]
          log('images', `[${idx}/${items.length}] ${result.files.length} 张候选，默认选第1张`)
        }
      } else if (model === 'kling') {
        const { generate: klingGen } = require('../kling-image-generator')
        const klingOpts = { outputDir: imagesDir, aspectRatio: ratio }
        if (refs.urls.length > 0) {
          klingOpts.styleImageUrl = refs.urls[0]
        }
        log('images', `[${idx}/${items.length}] 可灵生图: ${item.imagePrompt.substring(0, 60)}...`)
        result = await klingGen(item.imagePrompt, klingOpts)
        if (result.savedFiles && result.savedFiles.length > 0) {
          item.file = renameGeneratedFile(
            path.relative(dir, result.savedFiles[0]).replace(/\\/g, '/'),
            dir, idx, item.narration || item.shotDesc, ''
          )
        }
      } else {
        throw new Error(`不支持的模型: ${model}（支持: gemini, mj, kling）`)
      }

      if (item.file) {
        item.status = 'done'
        log('images', `[${idx}/${items.length}] 完成: ${item.file}`)
      } else {
        item.status = 'failed'
        item.error = '生成器未返回文件'
        log('images', `[${idx}/${items.length}] 失败: 生成器未返回文件`)
      }

      // 首尾帧模式：生成第二张图（lastFrame）
      if (item.status === 'done' && manifest.mode === 'framePair' && item.lastFramePrompt && !item.lastFrame) {
        await generateLastFrame(item, idx, items.length, manifest, dir, imagesDir, model, ratio, manifestPath)
      }
    } catch (err) {
      item.status = 'failed'
      item.error = err.message
      log('images', `[${idx}/${items.length}] 失败: ${err.message}`)
    }
    saveManifest(manifestPath, manifest)
  }
}

async function generateLastFrame(item, idx, total, manifest, dir, imagesDir, model, ratio, manifestPath) {
  try {
    item.status = 'generating'
    saveManifest(manifestPath, manifest)

    const firstFramePath = path.resolve(dir, item.file)
    let lastResult
    if (model === 'gemini') {
      const { edit: geminiEdit } = require('../gemini-image-generator')
      lastResult = await geminiEdit(item.lastFramePrompt, [firstFramePath], {
        outputDir: imagesDir,
        aspectRatio: ratio,
      })
    } else if (model === 'mj') {
      const { generate: mjGen } = require('../mj-image-generator')
      const mjOpts = { outputDir: imagesDir, aspectRatio: ratio, split: false }
      if (item.url) {
        mjOpts.referenceImages = [item.url]
        mjOpts.styleWeight = 200
      }
      lastResult = await mjGen(item.lastFramePrompt, mjOpts)
    } else if (model === 'kling') {
      const { generate: klingGen } = require('../kling-image-generator')
      lastResult = await klingGen(item.lastFramePrompt, {
        outputDir: imagesDir,
        styleImageUrl: item.url || '',
        aspectRatio: ratio,
      })
    }

    if (lastResult) {
      const files = lastResult.savedFiles || lastResult.files || []
      if (files.length > 0) {
        item.lastFrame = renameGeneratedFile(
          path.relative(dir, files[0]).replace(/\\/g, '/'),
          dir, idx, item.narration || item.shotDesc, 'last'
        )
        item.status = 'done'
        log('images', `[${idx}/${total}] lastFrame 完成: ${item.lastFrame}`)
      } else {
        item.status = 'failed'
        item.error = 'lastFrame 生成器未返回文件'
        log('images', `[${idx}/${total}] lastFrame 失败: 未返回文件`)
      }
    }
  } catch (err) {
    item.status = 'failed'
    item.error = `lastFrame 失败: ${err.message}`
    log('images', `[${idx}/${total}] lastFrame 失败: ${err.message}`)
  }
}

module.exports = { phaseImages }