/**
 * 票 26 消融 B（缓存回放）：15s 后 map-snapshot 全部回放缓存的同 URL 响应。
 *
 * 与消融 A 的区别：refresh 仍然成功、分页照走、对象照在图上 —— 只是数据完全相同。
 * 若 30s/60s 的周期性 stall 仍在 → 抽搐来自「refresh→整层重建」机制本身，
 * 与数据是否变化无关；这是对因果链最严格的检验。
 *
 * 运行：node .scratch/cockpit-real-data-wayfinding/verify/artifacts/t26/probe-jitter-replay.mjs
 */
import { cdpLaunch } from '../../../../cockpit-shell-panel-layout/verify/cdp-driver.mjs'

const CHROME = process.env.CHROME_PATH || 'C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe'
const TARGET_URL = process.env.T26_URL || 'http://127.0.0.1:8000/#/cockpit'
const WAIT_MS = Number(process.env.T26_WAIT_MS || 70000)
const POLL_MS = 250

const sleep = (ms) => new Promise((r) => setTimeout(r, ms))

function stats(values) {
    if (!values.length) return null
    const sorted = [...values].sort((a, b) => a - b)
    const at = (q) => sorted[Math.min(sorted.length - 1, Math.floor(q * sorted.length))]
    return { n: sorted.length, p50: at(0.5), p95: at(0.95), max: sorted[sorted.length - 1] }
}

const browser = await cdpLaunch({ executablePath: CHROME, width: 1280, height: 800 })
console.log(`Chrome: ${await browser.version()}  [消融 B：map-snapshot 缓存回放（15s 后）]`)
const page = await browser.newPage()

await page.goto(TARGET_URL, { timeout: 60000 })
await page.waitForSelector('.cockpit-shell', { timeout: 20000 })

await page.evaluate(() => {
    window.__t26 = { frames: [], longTasks: [], replayed: 0, recorded: 0 }
    let last = performance.now()
    const tick = (now) => {
        window.__t26.frames.push({ t: now, dt: now - last })
        last = now
        requestAnimationFrame(tick)
    }
    requestAnimationFrame(tick)
    try {
        new PerformanceObserver((list) => {
            for (const entry of list.getEntries()) window.__t26.longTasks.push({ start: entry.startTime, dur: entry.duration })
        }).observe({ entryTypes: ['longtask'] })
    } catch { /* 忽略 */ }

    const isSnapshot = (url) => String(url).includes('map-snapshot')
    const armAt = performance.now() + 15000
    const cache = new Map() // url -> { status, body }

    const nativeFetch = window.fetch.bind(window)
    window.fetch = async (...args) => {
        const url = String((args[0] && args[0].url) || args[0])
        if (!isSnapshot(url)) return nativeFetch(...args)
        if (performance.now() < armAt) {
            const resp = await nativeFetch(...args)
            try {
                const clone = resp.clone()
                cache.set(url, { status: resp.status, body: await clone.json() })
                window.__t26.recorded += 1
            } catch { /* 非 JSON 不缓存 */ }
            return resp
        }
        const hit = cache.get(url)
        if (!hit) return nativeFetch(...args) // 未见过的 URL 照常取
        window.__t26.replayed += 1
        return { ok: hit.status >= 200 && hit.status < 300, status: hit.status, json: async () => hit.body, headers: { get: () => null } }
    }

    // XHR 路径同款（axios 可能走 XHR；real 模式下 cockpitApi 用的是 fetch 还是 XHR 未知，两条都拦）。
    const XHR = XMLHttpRequest.prototype
    const nativeOpen = XHR.open
    XHR.open = function (method, url, ...rest) {
        this.__t26url = String(url)
        return nativeOpen.call(this, method, url, ...rest)
    }
    const nativeSend = XHR.send
    XHR.send = function (...args) {
        const el = this
        if (!isSnapshot(el.__t26url) || performance.now() < armAt) return nativeSend.apply(el, args)
        const hit = cache.get(el.__t26url)
        if (!hit) return nativeSend.apply(el, args)
        window.__t26.replayed += 1
        const body = JSON.stringify(hit.body)
        Object.defineProperty(el, 'readyState', { configurable: true, get: () => 4 })
        Object.defineProperty(el, 'status', { configurable: true, get: () => hit.status })
        Object.defineProperty(el, 'responseText', { configurable: true, get: () => body })
        Object.defineProperty(el, 'response', { configurable: true, get: () => body })
        setTimeout(() => {
            el.dispatchEvent(new Event('readystatechange'))
            el.dispatchEvent(new Event('load'))
            el.dispatchEvent(new Event('loadend'))
        }, 5)
        return undefined
    }
})

if (await page.$('[data-cockpit-intro]')) {
    await page.click('[data-cockpit-intro]')
    await page.waitForSelector('[data-cockpit-intro]', { hidden: true, timeout: 10000 }).catch(() => {})
}
await page.waitForFunction(
    () => ['ready', 'failed', 'disabled'].includes(document.querySelector('.cockpit-shell__map .map-canvas')?.dataset.mapEngine),
    { timeout: 40000 },
).catch(() => {})
await sleep(3000)

console.log(`静置采样 ${(WAIT_MS / 1000).toFixed(0)}s…`)
const deadline = Date.now() + WAIT_MS
while (Date.now() < deadline) await sleep(POLL_MS)

const result = await page.evaluate(() => {
    const frames = window.__t26.frames
    const start = frames.length ? frames[0].t : 0
    const out = []
    let bucket = []
    let bucketStart = start
    for (const frame of frames) {
        if (frame.t - bucketStart >= 5000) {
            out.push({ from: bucketStart - start, dts: bucket.map((f) => f.dt) })
            bucket = []
            bucketStart = frame.t
        }
        bucket.push(frame)
    }
    if (bucket.length) out.push({ from: bucketStart - start, dts: bucket.map((f) => f.dt) })
    return {
        windows: out.map((w) => ({ from: w.from, dts: w.dts })),
        longTasks: window.__t26.longTasks,
        replayed: window.__t26.replayed,
        recorded: window.__t26.recorded,
    }
})

console.log(`录制 ${result.recorded} 页 / 回放 ${result.replayed} 页`)
console.log('fps 窗口：')
for (const w of result.windows) {
    const s = stats(w.dts)
    console.log(`  ${(w.from / 1000).toFixed(1)}s p50=${s.p50} p95=${s.p95} max=${s.max}`)
}
const late = result.longTasks.filter((t) => t.start > 16000 && t.dur >= 100)
console.log(`15s 后长任务(≥100ms)：${late.length} 个 ${JSON.stringify(late.slice(0, 10))}`)

await browser.close()