// P20 结构对拍：把 v2.9.2 原文页（本地经典页，jsdom 真跑）与 Vue SSR 输出逐页签比「结构骨架」
//   = #root 下每个元素的 `tag.class…`（忽略 svg/canvas/script/style 与文本）
// 用法：node tools/struct_diff.mjs [gateway] [tab…]
import { readFileSync } from 'node:fs'
import { fileURLToPath, pathToFileURL } from 'node:url'
import { dirname, resolve } from 'node:path'
import { JSDOM, VirtualConsole } from 'jsdom'

const HERE = dirname(fileURLToPath(import.meta.url))
const GATEWAY = process.argv[2] || 'http://106.120.102.238:28084'
const TABS = process.argv.slice(3).length ? process.argv.slice(3)
  : ['overview', 'energy', 'component', 'fault', 'vibration', 'generation', 'decision', 'assistant', 'report', 'system']
const CLASSIC = resolve(HERE, '../../../release/web/detail_v2.html')

const norm = (s) => String(s || '').replace(/\s+/g, ' ').trim()

function skeletonIn(root) {
  const out = []
  const walk = (el) => {
    for (const c of Array.from(el.children)) {
      const tag = c.tagName.toLowerCase()
      if (tag === 'canvas' || tag === 'svg' || tag === 'script' || tag === 'style') continue
      // ★P23：Vue 的 SVG 图外壳（旧页直接内联 SVG，无包裹）⇒ 本层视为透明，不参与骨架
      if (tag === 'div' && (c.getAttribute('class') || '').includes('legacy-chart')) { walk(c); continue }
      // ★P27：`v-unwrap` 宿主在运行时被解包（SSR 不执行指令）⇒ 判据等价解包
      if ((c.getAttribute('class') || '').includes('unwrap-host')) { walk(c); continue }
      const cls = (c.getAttribute('class') || '').split(/\s+/).filter(Boolean).sort().join('.')
      out.push(tag + (cls ? '.' + cls : ''))
      walk(c)
    }
  }
  walk(root)
  return out
}

const API_KEEP = ['/api/maint_survey', '/api/facts', '/api/ont_chain', '/api/ask_models',
                  '/api/ask_status', '/api/vibcms', '/api/turbine', '/api/problem', '/api/channel']

function installFetch(window, state) {
  state.apis = state.apis || {}
  state.cache = state.cache || new Map()
  window.fetch = async (input, init) => {
    const raw = typeof input === 'string' ? input : (input && input.url) || String(input)
    const url = raw.startsWith('http') ? raw : GATEWAY + (raw.startsWith('/') ? raw : '/' + raw)
    if (state.cache.has(url)) {                       // ★P36 同轮同 URL 复用
      const c = state.cache.get(url)
      return { ok: true, status: 200, headers: new Map(), text: async () => c, json: async () => JSON.parse(c) }
    }
    const r = await fetch(url, init)
    const body = await r.text()
    if (r.ok) state.cache.set(url, body)
    let j = null
    try { j = JSON.parse(body) } catch { /* ignore */ }
    const path = url.slice(GATEWAY.length).split('?')[0]
    if (path === '/api/fleet' && !state.fleet) state.fleet = j
    if (path === '/api/vibcms' && !state.cms) state.cms = j
    if (API_KEEP.includes(path) && !state.apis[path]) state.apis[path] = j
    return { ok: r.ok, status: r.status, headers: r.headers, text: async () => body, json: async () => j }
  }
}

/** ★P36 预热：等网关把 fleet/curves 算定（避免基线页落到 pending/骨架）。 */
async function warmup(tries = 24, gapMs = 4000) {
  let fleet = null
  for (let k = 0; k < tries; k++) {
    try {
      const r = await fetch(GATEWAY + '/api/fleet')
      if (r.ok) {
        const j = await r.json()
        const settled = !j.pending && !j.m9_pending && !j.fleet_pending
        if (settled) { fleet = j; break }
      }
    } catch { /* 继续等 */ }
    await new Promise((x) => setTimeout(x, gapMs))
  }
  return fleet
}

/** generation 前置：把 /api/curves 追到出图（与呈现对拍同口径）。 */
async function awaitCurves(tries = 20, gapMs = 3000) {
  for (let k = 0; k < tries; k++) {
    const r = await fetch(GATEWAY + '/api/curves')
    if (r.ok) {
      const j = await r.json()
      if (!j.building && (j.figs || []).length) return j
    }
    await new Promise((r2) => setTimeout(r2, gapMs))
  }
  throw new Error('等 /api/curves 出图超时')
}

async function baseline(tab) {
  const state = {}
  if (!state.warmed) { await warmup(); state.warmed = true }
  if (tab === 'generation') { state.curves = await awaitCurves(); console.log('   [i] curves figs ' + (state.curves.figs || []).length) }
  const html = readFileSync(CLASSIC, 'utf8')
  const dom = new JSDOM(html, {
    url: GATEWAY + `/detail/v2#tab=${tab}`,
    runScripts: 'dangerously', pretendToBeVisual: true,
    virtualConsole: new VirtualConsole(),
    beforeParse: (w) => installFetch(w, state),
  })
  const doc = dom.window.document
  for (let i = 0; i < 120; i++) {
    const root = doc.getElementById('root')
    if (root && root.querySelector('.page-head')) break
    await new Promise((r) => setTimeout(r, 500))
  }
  // ★P36 等 DOM 稳定：连续 3 次子元素数一致才认为渲染定稿
  let last = -1, same = 0
  for (let i = 0; i < 60; i++) {
    const root = doc.getElementById('root')
    const n = root ? root.querySelectorAll('*').length : 0
    if (n === last) { if (++same >= 3) break } else { same = 0 }
    last = n
    await new Promise((r) => setTimeout(r, 700))
  }
  return { root: doc.getElementById('root'), data: state.fleet, cms: state.cms ?? null,
           curves: state.curves ?? null, apis: state.apis ?? {} }
}

async function vueSkel(tab, data, cms, curves, apis) {
  const entry = pathToFileURL(resolve(HERE, '../target/ssr/entry-server.js')).href
  const html = await (await import(entry)).renderTab(data, tab, null, cms, curves, apis)
  const dom = new JSDOM(`<div id="wrap">${html}</div>`)
  const wrap = dom.window.document.getElementById('wrap')
  const nav = wrap.querySelector('.wb-tabs')
  if (nav) nav.remove()
  return skeletonIn(wrap)
}

let bad = 0
for (const tab of TABS) {
  const { root, data, cms, curves, apis } = await baseline(tab)
  if (!root) { console.log(`[X] ${tab}: 基线未渲染`); bad++; continue }
  const a = skeletonIn(root)
  const b = await vueSkel(tab, data, cms, curves, apis)
  if (a.length === b.length && a.every((x, i) => x === b[i])) {
    console.log(`[OK] ${tab} 结构一致（${a.length} 个元素）`)
  } else {
    bad++
    const diffs = []
    for (let i = 0; i < Math.max(a.length, b.length) && diffs.length < 4; i++) {
      if (a[i] !== b[i]) diffs.push(`#${i} 基准=${a[i] || '∅'} · Vue=${b[i] || '∅'}`)
    }
    console.log(`[X]  ${tab} 元素数 基准 ${a.length} · Vue ${b.length}`)
    for (const d of diffs) console.log(`       ${d}`)
  }
}
console.log(`\n结构对拍结论: ${TABS.length - bad}/${TABS.length} 页签结构一致`)
process.exit(bad ? 9 : 0)