#!/usr/bin/env node
/**
 * token-saver-model-advisor.js · TSE Layer 1 · 2026-04-27
 * UserPromptSubmit · 分析 prompt 复杂度, 建议模型选择
 * 节流: 每会话每复杂度级别仅提醒 1 次
 * 行为: fail-open
 */
'use strict';

const fs = require('fs');
const path = require('path');
const CLAUDE_ROOT = require('./lib/root.js');
const readStdin = require('./lib/read-stdin.js');

const STATE_DIR = path.join(CLAUDE_ROOT, 'session-state');
const STATE_PATH = path.join(STATE_DIR, 'tse-model-advisor.json');

const SIMPLE = [
  /^(查找|搜索|找到?|在哪|哪个文件)/,
  /^(翻译|translate)\b/i, /^(格式化|format)\b/i,
  /^(解释|explain|what is|what does)\b/i,
  /^(列出|list|show)\b/i, /^(帮我看|看一下|看看)/,
  /^(改个?名|rename)\b/i, /^(运行|run|execute)\s+(test|build|lint)\b/i,
];
const COMPLEX = [
  /(架构|architecture|设计方案|system design)/i,
  /(全面审计|comprehensive audit|全栈审计)/i,
  /(从零开始|from scratch|end.to.end)/i,
  /(重构整个|refactor the entire|重新设计)/i,
  /(安全审查|security review|红队|red.team)/i,
  /(性能优化方案|performance optimization plan)/i,
  /(对比分析|comparative analysis|trade.off)/i,
];

function classify(p) {
  if (!p || p.length < 3) return null;
  for (const re of SIMPLE) { if (re.test(p.trim())) return 'simple'; }
  for (const re of COMPLEX) { if (re.test(p.trim())) return 'complex'; }
  if (p.trim().length < 25) return 'simple';
  return null;
}

function loadState() {
  try { return fs.existsSync(STATE_PATH) ? JSON.parse(fs.readFileSync(STATE_PATH, 'utf8')) : {}; } catch { return {}; }
}
function saveState(s) {
  try {
    if (!fs.existsSync(STATE_DIR)) fs.mkdirSync(STATE_DIR, { recursive: true });
    const tmp = STATE_PATH + '.tmp.' + process.pid;
    fs.writeFileSync(tmp, JSON.stringify(s, null, 2), 'utf8');
    fs.renameSync(tmp, STATE_PATH);
  } catch {}
}

(async () => {
  try {
    const hookData = await readStdin();
    const prompt = hookData.prompt || '';
    const sid = hookData.session_id || 'u';
    const level = classify(prompt);
    if (!level) process.exit(0);

    const state = loadState();
    const ss = state[sid] || { a: {}, ts: Date.now() };
    if (ss.a[level]) process.exit(0);
    ss.a[level] = true; ss.ts = Date.now();
    state[sid] = ss;
    const cutoff = Date.now() - 86400000;
    for (const k of Object.keys(state)) { if (state[k].ts < cutoff) delete state[k]; }
    saveState(state);

    const msg = level === 'simple'
      ? '[TSE·MODEL_ADVISOR] 简单任务检测。如当前是 Opus, 建议 /model sonnet 或 /model haiku 以节省 5 倍额度。子 Agent 请指定 model: "haiku"��'
      : '[TSE·MODEL_ADVISOR] 复杂任务检测。Opus 适合规划阶段。建议: 方案确定后切回 Sonnet 执行, 子 Agent 用 Sonnet/Haiku。';

    process.stdout.write(JSON.stringify({
      continue: true, suppressOutput: true,
      hookSpecificOutput: { hookEventName: 'UserPromptSubmit', additionalContext: msg }
    }));
    process.exit(0);
  } catch { process.exit(0); }
})();