#!/usr/bin/env node
'use strict'

/**
 * capture-previews — regenerate every skin's light/dark preview screenshots.
 *
 * Opens market/dist/preview.html (the v2 static renderer: the simulator
 * injects the skin's stylesheets into the official-facade snapshot and
 * paints declarative backgroundMedia; skin hooks JS is never executed) in headless Chromium and
 * screenshots each skin × {light, dark} into the skin source working tree,
 * satellites/dsh-skins/skins/<id>/preview/{light,dark}.jpg. dsh-skins is a
 * submodule and the market input pinned by its gitlink (market-inputs.lock.json),
 * so the previews land in the repository that owns the skins.
 *
 * Requires playwright + its chromium browser:
 *   npm i -D playwright && npx playwright install chromium
 * or run via npx:  npx playwright@latest install chromium
 *
 * Usage:
 *   node scripts/capture-previews              # all skins, light + dark
 *   node scripts/capture-previews xp miku      # only named skins
 *   node scripts/capture-previews --serve      # serve via http instead of file://
 *
 * Outputs 1440×900 JPEGs (quality 85) at device scale 1; the market cards
 * downscale them, so they stay crisp while the published package stays
 * small (the old 2880×1800 PNGs made dsh-client-ui-skin-center ~78MB).
 * Re-run after any skin change and commit the JPEGs in dsh-skins together with
 * the skin source. To see them in the market before that commit is pinned here,
 * read the submodule working tree:
 *
 *   pnpm market:fetch --local --force   # the working tree, not the pinned commit
 *   pnpm market:build                   # unpinned content: do not commit market/dist
 *
 * Once the submodule gitlink on this branch names the new dsh-skins commit, refresh
 * the committed copy with `pnpm market:fetch && pnpm market:build` and commit
 * market/dist together with the gitlink.
 */

const { execSync } = require('node:child_process')
const fs = require('node:fs')
const http = require('node:http')
const path = require('node:path')

const ROOT = path.resolve(__dirname, '..')
const MARKET_DIST = path.join(ROOT, 'market', 'dist')
const SKINS_REPO = path.join(ROOT, 'satellites', 'dsh-skins')

// --- tiny static server (fallback for environments where file:// screenshots
// --- misbehave) -------------------------------------------------------------
let server = null

/** True when `file` is strictly inside `root` (matched at a path boundary). */
function isInside(root, file) {
  const rel = path.relative(root, file)
  return rel === '' || (!rel.startsWith('..') && !path.isAbsolute(rel))
}

function serve() {
  const types = { '.html': 'text/html', '.js': 'text/javascript', '.mjs': 'text/javascript', '.png': 'image/png', '.jpg': 'image/jpeg', '.webp': 'image/webp' }
  server = http.createServer((req, res) => {
    const url = decodeURIComponent((req.url || '/').split('?')[0])
    const file = path.normalize(path.join(MARKET_DIST, url === '/' ? 'preview.html' : url))
    if (!isInside(MARKET_DIST, file)) { res.writeHead(403); return res.end('forbidden') }
    fs.readFile(file, (err, buf) => {
      if (err) { res.writeHead(404); return res.end('not found') }
      res.writeHead(200, { 'content-type': types[path.extname(file)] || 'application/octet-stream' })
      res.end(buf)
    })
  })
  return new Promise((resolve) => server.listen(0, '127.0.0.1', () => {
    resolve(`http://127.0.0.1:${server.address().port}`)
  }))
}

function loadPlaywright() {
  try { return require('playwright') } catch (e) { /* fall through */ }
  try {
    const local = path.join(ROOT, 'node_modules', 'playwright')
    return require(local)
  } catch (e) {
    console.error('playwright not found. Install it:\n  npm i -D playwright && npx playwright install chromium')
    process.exit(1)
  }
}

async function main() {
  const args = process.argv.slice(2)
  const want = args.filter((a) => !a.startsWith('--'))
  const useServer = args.includes('--serve')

  const manifest = JSON.parse(fs.readFileSync(path.join(MARKET_DIST, 'manifest.js'), 'utf8')
    .replace(/^\/\*[\s\S]*?\*\/\s*/, '')   // 头部生成注释
    .replace(/^window\.SKIN_MANIFEST = /, '')
    .replace(/;\s*$/, ''))
  let skins = manifest.skins
  if (want.length) {
    const set = new Set(want)
    skins = skins.filter((s) => set.has(s.id))
  }

  const base = useServer ? await serve() : 'file://' + MARKET_DIST
  console.log(`capture-previews: ${skins.length} skins × {light,dark} @ ${base}`)

  // hooks 动态场景皮肤清单（作用于 capture 渲染，不影响模拟器默认行为）
  const HOOK_SCENE_SKINS = ['maid-atelier', 'orca-link']

  const { chromium } = loadPlaywright()
  const browser = await chromium.launch()
  const page = await browser.newPage({ viewport: { width: 1440, height: 900 }, deviceScaleFactor: 1 })

  for (const skin of skins) {
    const skinDir = path.join(SKINS_REPO, 'skins', skin.id)
    if (!fs.existsSync(skinDir)) {
      throw new Error(`${skin.id}: ${path.relative(ROOT, skinDir)} not found — the dsh-skins submodule is missing or sits on another commit; run 'git submodule update --init satellites/dsh-skins'`)
    }
    const dir = path.join(skinDir, 'preview')
    fs.mkdirSync(dir, { recursive: true })
    for (const theme of ['light', 'dark']) {
      const url = `${base}/preview.html?skin=${skin.id}&theme=${theme}&chrome=0`
      await page.goto(url, { waitUntil: 'networkidle' })
      // 等皮肤样式注入完成：模拟器在 <html> 上写 data-dsh-skin（与真实加载器
      // 的作用域属性一致），或渲染错误横幅。
      await page.waitForFunction(() => {
        const err = document.getElementById('skinErr')
        if (err && err.style.display === 'block') return true
        return document.documentElement.dataset.dshSkin !== undefined
      }, undefined, { timeout: 10000 })
      const errText = await page.evaluate(() => {
        const el = document.getElementById('skinErr')
        return el && el.style.display === 'block' ? el.textContent : null
      })
      if (errText) throw new Error(`${skin.id}/${theme}: ${errText}`)
      // 等声明式背景画真正解码完成（冷启动首次加载 1600x900 WebP 可能慢于
      // 固定等待，只等 data-dsh-skin 会先于 renderSkinBackdrop 命中）
      await page.waitForFunction(() => {
        const layer = document.getElementById('skin-backdrop')
        if (!layer) return true
        const img = layer.querySelector('img')
        if (img) return img.complete && img.naturalWidth > 0
        const video = layer.querySelector('video')
        if (video) return video.readyState >= 2
        return true
      }, undefined, { timeout: 15000 })
      await page.waitForTimeout(300) // 让 scrim/过渡稳定
      // 部分皮肤的角色场景由 hooks.mjs 动态绘制（如 maid-atelier 的宫殿+双女仆），
      // 模拟器默认不执行皮肤 JS；capture 时对这类皮肤用最小 ctx shim 运行 apply()，
      // 让预览与真实观感一致（需 --serve：模块加载走 http）。
      if (useServer && HOOK_SCENE_SKINS.indexOf(skin.id) !== -1) {
        await page.evaluate(async (id) => {
          const mod = await import('/assets/skins/' + id + '/hooks.mjs?t=' + Date.now())
          const factory = mod && mod.default
          if (typeof factory !== 'function') return
          const hooks = factory()
          if (!hooks || typeof hooks.apply !== 'function') return
          hooks.apply({
            assetBase: '/assets/skins/' + id,
            scopeAttr: id,
            theme: { get: () => (document.body.dataset.dsDarkTheme !== undefined ? 'dark' : 'light') },
            onCleanup: function () {},
          })
        }, skin.id)
        await page.waitForTimeout(700)
      }
      const out = path.join(dir, `${theme}.jpg`)
      await page.screenshot({ path: out, type: 'jpeg', quality: 85 })
      console.log(`  ok ${skin.id}/${theme} → ${path.relative(ROOT, out)}`)
    }
  }

  await browser.close()
  if (server) server.close()
  console.log(`done. commit the previews in ${path.relative(ROOT, SKINS_REPO)}, then run: pnpm market:fetch --local --force && pnpm market:build`)
}

main().catch((err) => {
  console.error(err)
  process.exit(1)
})