/**
 * 用**真实 SSE 载荷**回放 F073 正文流式的整条链路（协调器 + 应用侧组装），
 * 断言「正文只出现一次」且版式为「卡片 → 正文 → 参考资料」。
 *
 * 为什么要有这个脚本：`verify-answer-stream.mjs` 用的是**理想化**的窄用例（delta 拼接 == 最终全文），
 * 而真后端经常在 `answer_end` 里给出**比增量拼接更长**的文本（2026-09-20 那份载荷：1309 → 1610 字，
 * 末尾补了追问建议）。这条路径上「应用侧记录的流式正文」会与上屏内容脱节 → 重排时按兜底分支处理
 * → **正文上屏两份、卡片被挤到两份正文中间**。用户从截图报告，用这个脚本复现并定位。
 *
 * 那条路径的回归现已用**合成载荷**钉在 `verify-answer-stream.mjs` 的【12】（不依赖外部文件）；
 * 本脚本的价值是**回放真抓包**——真载荷里 delta 片数、heartbeat 夹带、卡片/参考资料事件序
 * 都是合成的近似，出问题时先跑它，能直接看出是哪一段与预期不符。
 *
 * 怎么跑（先按 `_entry-coordinator.ts` 头部注释重新打包 `_coordinator.mjs`）：
 *   node harness/tools/verify-answer-stream-payload.mjs                          # 用下面的合成夹具
 *   node harness/tools/verify-answer-stream-payload.mjs <原始SSE文件>            # 回放真抓包
 * 载荷怎么来：浏览器 Network 面板把 `/api/chat` 的响应另存为文件（保持 `event: / data: ` 原样）。
 * ⚠️ 真抓包不入库（单份 600KB 量级）：想回放真载荷就显式传路径。
 */

import { readFileSync, existsSync } from 'node:fs';
import { fileURLToPath } from 'node:url';
import { dirname, join } from 'node:path';

const here = dirname(fileURLToPath(import.meta.url));
/** 默认夹具：与真抓包**同形态**（answer_end 比增量拼接多一截尾巴）的合成载荷，小到可以入库 */
const DEFAULT_FIXTURE = join(here, 'fixtures', 'answer-stream-tail.payload.md');
const payloadPath = process.argv[2] || DEFAULT_FIXTURE;

const {
  ApiChatCoordinator,
  applyAnswerStreamEnd,
  composeAroundStreamBody,
  resolveStreamedBodyAfterEnd,
  normalizeChatMarkdown,
} = await import('./_coordinator.mjs');

let failed = 0;
const check = (label, ok, detail) => {
  console.log(`${ok ? '  ✅' : '  ❌'} ${label}`);
  if (!ok) {
    failed++;
    if (detail !== undefined) {
      const text = typeof detail === 'string' ? detail : JSON.stringify(detail);
      console.log(`      实际：${String(text).slice(0, 240)}`);
    }
  }
};

if (!existsSync(payloadPath)) {
  console.error(`载荷文件不存在：${payloadPath}`);
  process.exit(2);
}
const raw = readFileSync(payloadPath, 'utf8');

/* ------------------------------------------------------------------ *
 * ① 载荷统计：先把「增量拼接 vs answer_end 全文」这条关键差异摆出来
 * ------------------------------------------------------------------ */
const parseEvents = (text) =>
  text
    .split(/\r?\n\r?\n+/)
    .map((block) => block.match(/^event: (\S+)\r?\ndata: ([\s\S]*)$/))
    .filter(Boolean)
    .map((m) => {
      let data = {};
      try {
        data = JSON.parse(m[2]).data || {};
      } catch {
        /* 坏帧忽略 */
      }
      return { name: m[1], data };
    });

const events = parseEvents(raw);
const counts = {};
for (const e of events) counts[e.name] = (counts[e.name] || 0) + 1;
const joined = events
  .filter((e) => e.name === 'answer_delta')
  .map((e) => e.data.text || '')
  .join('');
const endEvent = events.find((e) => e.name === 'answer_end');
const endText = endEvent?.data.text || '';
const normalizedFinal = normalizeChatMarkdown(endText);

console.log(`载荷：${payloadPath}`);
console.log('事件计数：', JSON.stringify(counts));
console.log(
  `增量拼接 ${joined.length} 字 / answer_end ${endText.length} 字 / 规整后 ${normalizedFinal.length} 字` +
    `（末尾额外 ${endText.length - joined.length} 字）`
);

/* ------------------------------------------------------------------ *
 * ② 回放：真实协调器 + 应用侧监听器（与 useBusinessAssistantChat 同逻辑）
 * ------------------------------------------------------------------ */
globalThis.fetch = async () =>
  new Response(
    new ReadableStream({
      start(controller) {
        controller.enqueue(new TextEncoder().encode(raw));
        controller.close();
      },
    }),
    { status: 200, headers: { 'Content-Type': 'text/event-stream' } }
  );

const coordinator = new ApiChatCoordinator({ baseUrl: 'http://stub', threadId: 'replay' });

/** 应用侧的 per-task 流状态（对应 useBusinessAssistantChat 里的 `stream`） */
const stream = { active: false, streamId: '', body: '' };
/** 应用侧的消息内容（对应 ai.content） */
let content = '';
const channelOrder = [];

coordinator.addEventListener('answerStreamStart', (p) => {
  stream.streamId = String(p?.streamId || '');
  stream.body = '';
  stream.active = true;
  channelOrder.push('streamStart');
});

// 增量走 message 通道上屏（流未开始时：卡片；流结束后：尾部追加）
coordinator.addEventListener('message', (msg) => {
  if (stream.active) {
    stream.body += msg;
    channelOrder.push(`message:${msg.slice(0, 16)}`);
  } else if (!content.includes('POLICY_TABLE') && msg.includes('POLICY_TABLE')) {
    channelOrder.push('message:cards');
  } else {
    channelOrder.push('append:trailing');
  }
  content += msg;
});

coordinator.addEventListener('answerStreamEnd', (p) => {
  if (!stream.active || String(p?.streamId || '') !== stream.streamId) return;
  const before = content;
  const finalText = String(p?.text ?? '');
  const next = applyAnswerStreamEnd(before, stream.body, finalText);
  if (next !== before) content = next;
  stream.body = resolveStreamedBodyAfterEnd(stream.body, finalText);
  stream.active = false;
  channelOrder.push('streamEnd');
});

coordinator.addEventListener('answerStreamCompose', (p) => {
  const before = content;
  const body = stream.body;
  const { next, matched } = composeAroundStreamBody(
    before,
    body,
    String(p?.leading || ''),
    String(p?.trailing || ''),
    String(p?.replacedLeading || '')
  );
  content = next;
  channelOrder.push(`compose(matched=${matched})`);
});

/** 载荷里有没有 `done`（没有 = 抓包不完整，协调器走断流兼容路径，不发 totalResponse） */
const hasDone = events.some((e) => e.name === 'done');
const errors = [];

const total = await new Promise((resolve) => {
  coordinator.addEventListener('totalResponse', (p) => resolve(p));
  coordinator.addEventListener('error', (p) => errors.push(p));
  void coordinator.generateAnswer('回放');
  setTimeout(() => resolve(null), hasDone ? 15000 : 500);
});
await new Promise((r) => setTimeout(r, 200));
if (errors.length) {
  console.log(`协调器 error：${errors.map((e) => e.code).join(',')}（载荷无 done 时属预期）`);
}

/* ------------------------------------------------------------------ *
 * ③ 断言
 * ------------------------------------------------------------------ */
console.log('\n【1】正文只出现一次');
// 用正文里一段**有辨识度**的中段做计数（取规整后全文的 1/3 处 40 字）
const probeStart = Math.floor(normalizedFinal.length / 3);
const probe = normalizedFinal.slice(probeStart, probeStart + 40).trim();
const bodyCount = probe ? content.split(probe).length - 1 : 0;
check(`正文中段片段在最终内容里出现 1 次（片段 ${JSON.stringify(probe.slice(0, 20))}）`, bodyCount === 1, `出现 ${bodyCount} 次`);

const headCount = content.split(normalizedFinal.slice(0, 20)).length - 1;
check(`正文开头 20 字出现 1 次`, headCount === 1, `出现 ${headCount} 次`);
check(
  `正文全文出现 1 次`,
  normalizedFinal ? content.split(normalizedFinal).length - 1 === 1 : true,
  `出现 ${normalizedFinal ? content.split(normalizedFinal).length - 1 : 0} 次`
);

console.log('\n【2】版式顺序：卡片 → 正文 → 参考资料');
const atCard = content.indexOf('POLICY_TABLE');
const atBody = normalizedFinal ? content.indexOf(normalizedFinal.slice(0, 20)) : -1;
const atRefs = content.indexOf('<ref_links>');
check('含政策卡片标记', atCard >= 0);
check('含参考资料标记', atRefs >= 0);
check(
  '卡片在正文之前',
  atCard >= 0 && atBody >= 0 && atCard < atBody,
  `卡片@${atCard} 正文@${atBody}`
);
check('正文在参考资料之前', atBody >= 0 && atRefs >= 0 && atBody < atRefs, `正文@${atBody} 参考资料@${atRefs}`);

// 人眼可读的上屏结构：按出现位置列出各内容块，便于和截图对照
{
  const marks = [
    ['思考中卡片 <scope>', '<scope'],
    ['政策卡片 POLICY_TABLE', 'POLICY_TABLE'],
    ['补问卡片 <question-cards>', '<question-cards>'],
    ['企业微信二维码 <cipa', '<cipa'],
    ['参考资料 <ref_links>', '<ref_links>'],
  ]
    .map(([label, needle]) => ({ label, at: content.indexOf(needle) }))
    .filter((m) => m.at >= 0)
    .sort((a, b) => a.at - b.at);
  const bodyAt = normalizedFinal ? content.indexOf(normalizedFinal.slice(0, 20)) : -1;
  const rows = [...marks, ...(bodyAt >= 0 ? [{ label: `正文（${normalizedFinal.length} 字）`, at: bodyAt }] : [])].sort(
    (a, b) => a.at - b.at
  );
  console.log('  上屏结构（按位置）：');
  for (const r of rows) console.log(`    @${String(r.at).padStart(6)}  ${r.label}`);
  console.log(`  上屏内容总长：${content.length} 字`);
}

console.log('\n【3】收尾链路（F079 顺序下应当**没有整块重排**）');
// 卡片在 answer_start 之前就上屏了 → 收尾只需把尾部纯追加，不该发 answerStreamCompose。
// 发了 compose 就意味着应用层要整块重写 → 用户会看到「正文先渲一遍，再从头渲一遍」。
check(
  '**没有发出 answerStreamCompose**（不整块重写 → 界面不重渲）',
  !channelOrder.some((x) => x.startsWith('compose')),
  `收到 ${channelOrder.filter((x) => x.startsWith('compose')).length} 次`
);
check(
  '尾部（参考资料）作为独立追加发出',
  channelOrder.some((x) => x === 'append:trailing'),
  channelOrder.at(-1)
);
if (hasDone) {
  check('totalResponse 里正文出现 1 次', !!total && !!normalizedFinal && String(total.answer || '').split(normalizedFinal).length - 1 === 1, total ? `出现 ${String(total.answer || '').split(normalizedFinal).length - 1} 次` : '未收到 totalResponse');
} else {
  console.log('  ⏭️  载荷没有 done 事件（走断流兼容路径，不发 totalResponse）——跳过该断言');
}
console.log('\n【4】兜底路径回归：流式正文没同步到上屏长度（= 本轮修的 bug）也不能重复');
{
  // 直接调纯函数，喂「上屏内容 = 完整正文，记录的正文 = 短一截的前缀」这种错位状态
  const staleBody = joined ? normalizeChatMarkdown(joined) : '';
  const { next, matched } = composeAroundStreamBody(
    normalizedFinal,
    staleBody,
    '<POLICY_TABLE>卡片</POLICY_TABLE>',
    '<ref_links>参考</ref_links>'
  );
  const dup = staleBody ? next.split(staleBody).length - 1 : 0;
  const head = normalizedFinal.slice(0, 20);
  check('后缀不匹配时落兜底分支（matched=false）', matched === false, `matched=${matched}`);
  check('兜底分支里正文仍只出现 1 次（不重复插入）', dup === 1, `出现 ${dup} 次`);
  check('兜底分支里正文没被丢掉', next.includes(head));
  check(
    '兜底分支里卡片仍在正文之前',
    next.indexOf('POLICY_TABLE') < next.indexOf(head),
    `卡片@${next.indexOf('POLICY_TABLE')} 正文@${next.indexOf(head)}`
  );
  check(
    '兜底分支里参考资料仍在正文之后',
    next.indexOf('<ref_links>') > next.indexOf(head),
    `正文@${next.indexOf(head)} 参考@${next.indexOf('<ref_links>')}`
  );
}

console.log(`\n${failed === 0 ? '✅ 全部通过' : `❌ ${failed} 项未通过`}`);
process.exit(failed === 0 ? 0 : 1);