/**
 * 票 75 变异测试：证明 90 天分窗合并的每条关键断言抓得住它要防的缺陷。
 *
 *   M1 合并丢趋势（只留首窗）        → A2 必须红（90 天只显示 30 天）
 *   M2 计数不求和（取首窗）          → A1 必须红（13 变 0）
 *   M3 处置率不重算（抄首窗百分比）   → A3 必须红（0% 冒充 44%）
 *   M4 分析 bucket 求和丢失          → B5 必须红（类型合计变 1 窗）
 *   M5 百分比相加不重算              → B4 必须红（50%+25%≠75% 的老错误）
 *   M6 分窗被拆掉（>31 天仍单请求）   → C1 必须红（撞 400，界面「最多31天」复现）
 *   M7 一窗失败仍合并其余            → C4 必须红（3/4 窗冒充 90 天）
 *   M8 31 天提示复活                 → D1 必须红（误导性提示回屏）
 *
 * 运行：node .scratch/cockpit-real-data-wayfinding/verify/t75-mutations.mjs
 */
import assert from 'node:assert/strict'
import { closeSync, mkdtempSync, openSync, readFileSync, rmSync, writeFileSync } from 'node:fs'
import { spawnSync } from 'node:child_process'
import { tmpdir } from 'node:os'
import { join } from 'node:path'
import { fileURLToPath } from 'node:url'

const repoRoot = fileURLToPath(new URL('../../../', import.meta.url))
const GATE = fileURLToPath(new URL('t75-90d-multi-window.mjs', import.meta.url))
const srcPath = (rel) => `${repoRoot}src/modules/cockpit/${rel}`

const reportDir = mkdtempSync(join(tmpdir(), 't75-mutations-'))
function runGate() {
    const outPath = join(reportDir, 'stdout.txt')
    const errPath = join(reportDir, 'stderr.txt')
    const out = openSync(outPath, 'w')
    const err = openSync(errPath, 'w')
    let status = 0
    try {
        status = spawnSync(process.execPath, [GATE], { stdio: ['ignore', out, err] }).status
    } finally {
        closeSync(out)
        closeSync(err)
    }
    return { output: `${readFileSync(outPath, 'utf8')}${readFileSync(errPath, 'utf8')}`, status }
}

function failingNames(output) {
    return [...output.matchAll(/^FAIL ([^:]+):/gm)].map((match) => match[1])
}

let injected = 0
let proved = 0
function mutate(label, file, from, to, expectRed) {
    const path = srcPath(file)
    const original = readFileSync(path, 'utf8')
    const candidates = [from, from.replace(/\n/g, '\r\n')]
    const needle = candidates.find((candidate) => original.includes(candidate))
    if (!needle) {
        console.error(`FAIL ${label}: 变异源未命中（文件形状已变，需人工更新变异脚本）`)
        injected += 1
        return
    }
    injected += 1
    writeFileSync(path, original.replace(needle, to), 'utf8')
    runAndJudge(label, original, path, expectRed)
}

function runAndJudge(label, original, path, expectRed) {
    let caught = false
    let how = ''
    try {
        const { output, status } = runGate()
        const red = failingNames(output)
        if (red.includes(expectRed)) {
            caught = true
            how = `${expectRed} 转红`
        } else if (status !== 0 && /does not provide an export|SyntaxError|Cannot find (module|export)/.test(output)) {
            caught = true
            how = '闸门整体加载失败（导出缺失/语法错）— 崩溃式抓住'
        } else if (status !== 0) {
            how = `退出码 ${status} 但目标断言未红（红项：${red.join(', ') || '无'}）— 判据不明，按未抓住记`
        } else {
            how = '未转红（假绿！闸门仍全绿）'
        }
        console.log(`${caught ? 'PASS' : 'FAIL'}  ${label} → ${how}`)
        if (caught) proved += 1
    } finally {
        writeFileSync(path, original, 'utf8')
        assert.equal(readFileSync(path, 'utf8'), original, `${label}: 还原失败`)
    }
}

// ---- 效率合并（services/warningResponseApi.js 的 mergeEfficiencyPayloads）----

mutate(
    'M1-efficiency-merge-drops-trend',
    'services/warningResponseApi.js',
    `        for (const row of Array.isArray(payload.durationTrend) ? payload.durationTrend : []) {
            if (seenBuckets.has(row.timeBucket)) continue
            seenBuckets.add(row.timeBucket)
            durationTrend.push(row)
        }`,
    ``,
    'A2 趋势按时序拼接且去重（720×3+17=2177 个小时桶，升序）',
)

mutate(
    'M2-efficiency-counts-take-last-window',
    'services/warningResponseApi.js',
    `        totalEvents += countOf(summary.totalEvents)`,
    `        totalEvents = countOf(summary.totalEvents)`,
    // 注：`+=` 变 `||=` 的写法对本数据是**等价变异**（前两窗为 0），不采用；取「末窗覆盖」才可观测。
    'A1 计数跨窗求和（totalEvents=0+0+13+0=13，不由单窗冒充 90 天）',
)

mutate(
    'M3-handling-rate-copied-not-recomputed',
    'services/warningResponseApi.js',
    `    const numerator = stateCounts.filter((row) => row.stateCode === 5).reduce((sum, row) => sum + row.count, 0)`,
    `    const numerator = countOf((list[0].summary && list[0].summary.handlingEfficiency || {}).numerator)`,
    'A3 处置率用合并后状态计数重算（分子=已结案4，分母=可计入9 → 44.44%）',
)

// ---- 分析合并（mergeAnalysisPayloads）----

mutate(
    'M4-analysis-total-count-takes-last-window',
    'services/warningResponseApi.js',
    `        totalCount += countOf(payload.totalCount)`,
    `        totalCount = countOf(payload.totalCount)`,
    // 注 1：维度级 `entry.totalCount` 的「末窗覆盖」对本数据等价（w3=13、w4 无该维度），
    // 不可观测；B1 断言的是**载荷级** totalCount（末窗 w4=0 → 0 ≠ 13，才可观测）。
    // 注 2：w1/w2 的维度桶为空数组，"丢弃后窗同码桶"同样不可观测。
    'B1 totalCount 跨窗求和（13）',
)

mutate(
    'M5-analysis-percentage-added-not-recomputed',
    'services/warningResponseApi.js',
    `                percentage: entry.totalCount > 0 ? ((bucket.count / entry.totalCount) * 100).toFixed(2) : '0.00',`,
    `                percentage: bucket.percentage,`,
    'B4 percentage 重算而不是各窗相加（EVENT_TYPE 首桶 = count/totalCount×100）',
)

// ---- 分窗机制 ----

mutate(
    'M6-window-splitting-removed',
    'services/warningResponseApi.js',
    `    const windows = historyWindows(range.startTime, range.endTime)
    if (windows.length <= 1) {`,
    `    const windows = historyWindows(range.startTime, range.endTime)
    if (true) {`,
    'C1 90 天触发分窗：恰好 4 次请求、每次 ≤30 天（不是一次打 90 天撞 400）',
)

mutate(
    'M7-partial-failure-still-merges',
    'services/warningResponseApi.js',
    `        const failed = results.find((result) => ![SECTION_STATE.SUCCESS, SECTION_STATE.STALE, SECTION_STATE.EMPTY].includes(result.state))
        if (failed) return failed`,
    `        // 变异：窗失败被吞掉，拿其余窗冒充全量
        const failed = null
        if (failed) return failed`,
    'C4 一窗失败 → 整分区 FAILED（不拿 3/4 窗冒充 90 天）',
)

// ---- 提示 ----

mutate(
    'M8-31d-note-resurrected',
    'components/WarningResponsePane.vue',
    `        <p v-if="!eventStore.loading && section && section.reason && /历史接口回显/.test(section.reason)" class="warning-response-pane__range-status" role="alert">{{ section.reason }}</p>`,
    `        <p v-if="!eventStore.loading && eventStore.range === '90d' && panelId !== 'historyAnalysis'" class="warning-response-pane__range-status" role="status">
            当前接口最多支持31天统计，请选择近7天或近30天；近90天历史趋势可正常查询。
        </p>
        <p v-if="!eventStore.loading && section && section.reason && /历史接口回显/.test(section.reason)" class="warning-response-pane__range-status" role="alert">{{ section.reason }}</p>`,
    'D1 「最多支持31天」提示已撤（不再成立；误导比没有提示更糟）',
)

console.log('')
console.log(`T75 变异测试：${proved}/${injected} 处变异被对应断言抓住。`)
rmSync(reportDir, { recursive: true, force: true })
if (proved < injected) process.exit(1)