#!/usr/bin/env node
/**
 * E 批：图片 lazy-load 治理
 * 在长列表页的 <image> 标签上补 lazy-load（若尚未有 lazy-load 属性）
 *
 * 策略：
 * - 对 <image ...> 不含 lazy-load 的标签补上 lazy-load
 * - 跳过已有 lazy-load 的标签
 * - 仅处理已识别的长列表页（discover / article-center / shop / activity / growth 等）
 */
const fs = require('fs')
const path = require('path')

const ROOT = path.resolve(__dirname, '..')
const EXCLUDE_DIRS = new Set(['node_modules', 'dist', 'unpackage', '.git', 'docs'])

// 需要治理的长列表页面/组件（按父目录分组，walk 时过滤）
const TARGET_PATTERNS = [
  'pages/discover/',
  'pages/article-center/',
  'pages/shop/',
  'pages/activity/',
  'pages/growth/',
  'pages/promotion/',
  'components/DimensionActivities.vue',
  'components/DimensionProducts.vue',
  'components/RecommendedFeed.vue',
  'components/ArticleBookshelf.vue',
  'components/FamilyFeed.vue',
  'components/daily-task-card.vue',
]

// 模式：找到 <image ...> 中不含 lazy-load 的，加上 lazy-load
// 匹配：<image ...attrs...>（不含 lazy-load），在后面某个位置补
const IMG_TAG_RE = /<image\s([^>]*)>/gi

function processFile(filePath) {
  const src = fs.readFileSync(filePath, 'utf8')
  // 只处理包含长列表 image 的文件（启发式：有 v-for 或 list/data 字样的文件优先）
  const hasLoop = /v-for\s*=/.test(src) || /v_loop/.test(src)
  if (!hasLoop) return { changed: false, count: 0 }

  let result = src
  let count = 0
  result = result.replace(IMG_TAG_RE, (fullMatch, attrs) => {
    if (/lazy-load/.test(attrs)) return fullMatch // 已有 lazy-load，跳过
    // 在标签闭合 `>`（可能为 `/>`）前插入 lazy-load
    if (fullMatch.endsWith('/>')) {
      return fullMatch.slice(0, -2) + ' lazy-load />'
    }
    return fullMatch.slice(0, -1) + ' lazy-load>'
  })

  count = (result.match(/lazy-load/g) || []).length - (src.match(/lazy-load/g) || []).length
  if (count > 0) {
    fs.writeFileSync(filePath, result, 'utf8')
  }
  return { changed: count > 0, count }
}

function walk(dir, out = []) {
  for (const name of fs.readdirSync(dir)) {
    if (EXCLUDE_DIRS.has(name)) continue
    const p = path.join(dir, name)
    const st = fs.statSync(p)
    if (st.isDirectory()) walk(p, out)
    else if (name.endsWith('.vue')) out.push(p)
  }
  return out
}

function main() {
  const allFiles = walk(ROOT)
  const targets = allFiles.filter(f => {
    const rel = path.relative(ROOT, f).split(path.sep).join('/')
    return TARGET_PATTERNS.some(p => rel.startsWith(p))
  })

  let grandTotal = 0
  const log = []
  for (const f of targets) {
    const rel = path.relative(ROOT, f)
    const r = processFile(f)
    if (r.changed) {
      grandTotal += r.count
      log.push(`${r.count.toString().padStart(3)}  ${rel}`)
    }
  }
  console.log(`\n=== E 批 lazy-load 补全完成 ===`)
  console.log(`新增 lazy-load: ${grandTotal} 处`)
  log.sort((a, b) => parseInt(b.split(' ')[0]) - parseInt(a.split(' ')[0]))
  for (const line of log.slice(0, 30)) console.log(line)
}

main()