/**
 * 票 59 闸门变异测试：证明 t59 的每条关键断言**抓得住它要防的缺陷**（与 t46-mutations 同一纪律）。
 *
 * 做法：对源文件做**单点**变异注入 → 跑 t59 → 断言指定断言转红 → 按字节还原并校验一致。
 * 变异只在本脚本运行期间存活几秒，跑完即还原。
 *
 * 十三条变异对应票 59 的真实风险：
 *   M1 窗口全列阈值被改成 5 → W2 必须红（7 页就收缩=条文 2 的「≤7 全列」失守）
 *   M2 右侧省略号不推了 → W3 必须红（收缩窗口缺省略号=「恒含省略号」失守）
 *   M3 跳页夹回放 NaN 过 → J3 必须红（页码状态被 NaN 污染，控件画成「第 NaN 页」）
 *   M4 跳页只夹下不夹上 → J2 必须红（超界页跳进空页）
 *   M5 一页也画控件 → S1 必须红（条文 4「一页不画」失守）
 *   M6 翻页出口改名出第二个事件 → S2 必须红（「共用同一翻页出口」失守）
 *   M7 到边按钮不再禁用 → S3 必须红（票 46 既有语义回退）
 *   M8 当前页 aria-current 丢了 → S4 必须红（条文 9 失守）
 *   M9 跳页绕过 clampPage → S6 必须红（夹回判据名存实亡）
 *   M10 兼容再导出被改名 → t59 具名 import 加载失败=崩溃式抓住（条文 11 的单源锚）
 *   M11 组件里重新长出翻页算术 → C4 必须红（条文 11「禁止组件重写算术」）
 *   M12 工单回退成全量直渲 → C3 必须红（本票「工单状态新接入分页」交付被吃掉）
 *   M13 换分类不再回第 1 页 → C5 必须红（条文 6 复位规则失守）
 *
 * 运行：node .scratch/cockpit-real-data-wayfinding/verify/t59-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('t59-shared-pager.mjs', import.meta.url))
const srcPath = (rel) => `${repoRoot}src/modules/cockpit/${rel}`

/**
 * 跑闸门并取回输出。
 * 刻意用**文件重定向**而不是管道捕获（t46 实测：Windows 沙箱下捕获子进程 stdio 的命名管道
 * 是文档化的边界（EPERM），管道版拿回空输出 → 变异全部"未转红"的假信号）。
 */
const reportDir = mkdtempSync(join(tmpdir(), 't59-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')
    // 变异源文本按 CRLF 归一后再匹配（票 37 实测踩过：行尾不一致时 replace 静默不命中）。
    const candidates = [from, from.replace(/\n/g, '\r\n')]
    const needle = candidates.find((candidate) => original.includes(candidate))
    if (!needle) {
        console.error(`FAIL ${label}: 变异源未命中（文件形状已变，需人工更新变异脚本）`)
        injected += 1
        return
    }
    injected += 1
    writeFileSync(path, original.replace(needle, to), 'utf8')
    let caught = false
    let how = ''
    try {
        const { output, status } = runGate()
        const red = failingNames(output)
        if (red.includes(expectRed)) {
            caught = true
            how = `${expectRed} 转红`
        } else if (status !== 0 && /does not provide an export|SyntaxError|Cannot find (module|export)/.test(output)) {
            // 崩溃也算抓住（导出改名后闸门具名 import 加载失败），单列不与"断言转红"混淆。
            caught = true
            how = '闸门整体加载失败（导出缺失）— 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`)
    }
}

// ---- pagination.js：窗口与夹回（纯函数闸门） ----

mutate(
    'M1-window-full-list-threshold-shrunk',
    'domain/pagination.js',
    '    if (total <= 7) {',
    '    if (total <= 5) {',
    'W2-seven-pages-still-full',
)

mutate(
    'M2-shrink-drops-right-ellipsis',
    'domain/pagination.js',
    '    if (windowEnd < total - 1) items.push(PAGE_ELLIPSIS)',
    '    if (false) items.push(PAGE_ELLIPSIS)',
    'W3-eight-pages-shrinks',
)

mutate(
    'M3-clampPage-lets-NaN-through',
    'domain/pagination.js',
    '    if (!Number.isFinite(num)) return 1',
    '    if (!Number.isFinite(num)) return num',
    'J3-non-numeric-clamps-to-one',
)

mutate(
    'M4-clampPage-loses-upper-bound',
    'domain/pagination.js',
    '    return Math.min(Math.max(1, Math.trunc(num)), limit)',
    '    return Math.max(1, Math.trunc(num))',
    'J2-clamp-to-range',
)

// ---- PagerNav.vue：共享控件的行为契约 ----

mutate(
    'M5-single-page-still-renders-pager',
    'components/PagerNav.vue',
    'const visible = computed(() => props.pageCount > 1)',
    'const visible = computed(() => props.pageCount >= 1)',
    'S1-one-page-renders-nothing',
)

mutate(
    'M6-second-page-outlet',
    'components/PagerNav.vue',
    "    emit('page', target)",
    "    emit('turn', target)",
    'S2-single-page-outlet',
)

mutate(
    'M7-edge-disable-gone',
    'components/PagerNav.vue',
    ':disabled="page <= 1" data-page-prev',
    ':disabled="false" data-page-prev',
    'S3-edge-disabled-with-placeholder',
)

mutate(
    'M8-aria-current-dropped',
    'components/PagerNav.vue',
    `:aria-current="item === page ? 'page' : undefined"`,
    ':aria-current="undefined"',
    'S4-aria-group-current',
)

mutate(
    'M9-jump-skips-clamp',
    'components/PagerNav.vue',
    '    const target = clampPage(jumpValue.value, props.pageCount)',
    '    const target = Number(jumpValue.value)',
    'S6-jump-goes-through-clamp-and-same-outlet',
)

// ---- 兼容再导出（条文 11 的单源锚）：改名后闸门加载失败=崩溃式抓住 ----

mutate(
    'M10-compat-export-renamed',
    'domain/equipmentDetailView.js',
    "export { PAGE_SIZE as HISTORY_PAGE_SIZE, pagedRows } from './pagination.js'",
    "export { PAGE_SIZE as HISTORY_PAGE_SIZE, pagedRows as pagedRowsV2 } from './pagination.js'",
    'P2-compat-export-is-same-function',
)

// ---- 消费方：设备详情三清单 ----

mutate(
    'M11-second-arithmetic-in-component',
    'components/EquipmentDetailSections.vue',
    '    return pagedRows(visibleRows(panel), pages.value[panel.name] || 1)',
    '    const list = visibleRows(panel); const p = pages.value[panel.name] || 1; return { rows: list.slice((p - 1) * 10, p * 10), page: p, pageCount: Math.ceil(list.length / 10), total: list.length }',
    'C4-no-local-pagination-arithmetic',
)

mutate(
    'M12-orders-revert-to-full-render',
    'components/EquipmentDetailSections.vue',
    'v-for="(order, index) in pagedOf(panel).rows"',
    'v-for="(order, index) in visibleRows(panel)"',
    'C3-orders-paginated',
)

mutate(
    'M13-category-keeps-page',
    'components/EquipmentDetailSections.vue',
    '    pages.value = { ...pages.value, [panelName]: 1 }',
    '    pages.value = pages.value',
    'C5-reset-rules-intact',
)

console.log('')
console.log(`T59 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)