#!/usr/bin/env node
'use strict';
/**
 * Phase 1 · T1.2 + T1.6 补丁 — SessionStart MCP Probe Hook
 *
 * 目的:
 *   1. 创建 hooks/session-start-mcp-probe.js (轻量每日探测)
 *   2. 注册到 settings.json 的 UserPromptSubmit (Bookworm 无 SessionStart 键)
 *
 * 设计:
 *   - 日级守卫: 今日 snapshot 存在则 1ms 返回
 *   - 轻量探测: 只校验命令存在性 / URL 格式，不 spawn MCP
 *   - Fail-open: 任何异常 exit 0，不阻断用户输入
 *   - Budget: 首次 <500ms，后续 <5ms
 *   - Feature flag: ~/.claude/.bookworm-features.json.mcp_probe=false 可关闭
 *
 * 幂等:
 *   - sentinel: PHASE1_T1_2_MCP_PROBE_HOOK_2026_04_24
 *   - settings.json: 通过 command 字符串唯一性检测
 *
 * 原子性:
 *   - hook 文件: tmp + rename
 *   - settings.json: .bak.phase1-t1.2 + tmp + rename
 *
 * 回滚:
 *   - 删除 hook 文件 + 从 settings.json 的 UserPromptSubmit 数组移除对应条目
 *   - 或在 .bookworm-features.json 设 mcp_probe=false
 */

const fs = require('fs');
const path = require('path');

const CLAUDE_ROOT = path.join(__dirname, '..', '..');
const HOOKS_DIR = path.join(CLAUDE_ROOT, 'hooks');
const HOOK_TARGET = path.join(HOOKS_DIR, 'session-start-mcp-probe.js');
const SETTINGS_FILE = path.join(CLAUDE_ROOT, 'settings.json');
const SETTINGS_BAK = SETTINGS_FILE + '.bak.phase1-t1.2';
const SENTINEL = 'PHASE1_T1_2_MCP_PROBE_HOOK_2026_04_24';
const HOOK_CMD = 'node C:/Users/leesu/.claude/hooks/session-start-mcp-probe.js';

const HOOK_CONTENT = `#!/usr/bin/env node
'use strict';
/**
 * SessionStart MCP Probe (Phase 1 · T1.2)
 * sentinel: ${SENTINEL}
 *
 * 事件: UserPromptSubmit (Bookworm 无 SessionStart 键，用 UserPromptSubmit + 日期守卫替代)
 * 目的: 每日首次会话轻量探测 MCP 配置健康度，结果写 logs/mcp-health-<date>.json
 *
 * 预算:
 *   - 今日 snapshot 已存在: <5ms (fs.existsSync 快速返回)
 *   - 首次运行: <500ms (22 个 MCP 的命令存在性检查)
 *
 * 容错:
 *   - Feature flag 关闭: 立即 exit 0
 *   - 任何异常: exit 0 (fail-open，永不阻断用户输入)
 *
 * 不做的事:
 *   - 不 spawn MCP 子进程 (太慢，交给 /mcp-probe 技能)
 *   - 不做实际 HTTP 请求
 *   - 不修改 .claude.json
 */

const fs = require('fs');
const path = require('path');
const os = require('os');

const HOME = process.env.USERPROFILE || process.env.HOME || os.homedir();
const CLAUDE_ROOT = process.env.CLAUDE_HOME ||
  (fs.existsSync(path.join(HOME, '.claude')) ? path.join(HOME, '.claude') : HOME);
const LOGS_DIR = path.join(CLAUDE_ROOT, 'logs');
const FEATURE_FLAGS_FILE = path.join(CLAUDE_ROOT, '.bookworm-features.json');
const TODAY = new Date().toISOString().slice(0, 10);
const HEALTH_FILE = path.join(LOGS_DIR, 'mcp-health-' + TODAY + '.json');
const CONFIG_FILE = path.join(HOME, '.claude.json');

function safeExit() { process.exit(0); }

// 已知在 PATH 上的命令（避免 which 调用开销）
const WELL_KNOWN_CMDS = /^(npx|node|python|python3|bash|sh|pnpm|yarn|uvx|go|deno|bun)$/;

function commandPlausible(cmd) {
  if (!cmd || typeof cmd !== 'string') return false;
  if (path.isAbsolute(cmd)) return fs.existsSync(cmd);
  // Windows 可能配置带 .cmd/.exe/.bat 后缀 (e.g. npx.cmd)，剥离后比对已知命令
  const stripped = cmd.replace(/\\.(exe|cmd|bat)$/i, '');
  if (WELL_KNOWN_CMDS.test(stripped)) return true;
  // 回退: 按 PATH 扫描 (受限于 PATH 数量，10-30 次 existsSync 可接受)
  const PATH_DIRS = (process.env.PATH || process.env.Path || '').split(path.delimiter).filter(Boolean);
  const candidates = [cmd, cmd + '.exe', cmd + '.cmd', cmd + '.bat'];
  for (const dir of PATH_DIRS) {
    for (const c of candidates) {
      try { if (fs.existsSync(path.join(dir, c))) return true; } catch {}
    }
  }
  return false;
}

function probeMcp(name, cfg) {
  try {
    if (cfg && (cfg.type === 'http' || cfg.type === 'sse')) {
      const hasUrl = !!cfg.url && /^https?:\\/\\//.test(cfg.url);
      return {
        kind: cfg.type,
        url: cfg.url || null,
        urlValid: hasUrl,
        reachable: hasUrl
      };
    }
    // 默认 stdio
    const command = (cfg && cfg.command) || '';
    const exists = commandPlausible(command);
    return {
      kind: 'stdio',
      command,
      commandExists: exists,
      reachable: exists
    };
  } catch (e) {
    return { error: String(e.message || e), reachable: false };
  }
}

function main() {
  // Feature flag 检查
  try {
    if (fs.existsSync(FEATURE_FLAGS_FILE)) {
      const flags = JSON.parse(fs.readFileSync(FEATURE_FLAGS_FILE, 'utf8'));
      if (flags && flags.mcp_probe === false) return safeExit();
    }
  } catch {}

  // 今日 snapshot 已存在 → 跳过 (日级守卫)
  if (fs.existsSync(HEALTH_FILE)) return safeExit();

  // 读取 MCP 配置
  let mcpServers = {};
  try {
    const cfg = JSON.parse(fs.readFileSync(CONFIG_FILE, 'utf8'));
    mcpServers = cfg.mcpServers || {};
  } catch {
    return safeExit();
  }

  const results = {};
  let reachable = 0;
  let unreachable = 0;
  const unreachableList = [];

  for (const name of Object.keys(mcpServers)) {
    const r = probeMcp(name, mcpServers[name]);
    results[name] = r;
    if (r.reachable) reachable++;
    else { unreachable++; unreachableList.push(name); }
  }

  const snapshot = {
    schema_version: 1,
    date: TODAY,
    probedAt: new Date().toISOString(),
    probeKind: 'lightweight-static',
    totalMcps: Object.keys(mcpServers).length,
    reachable,
    unreachable,
    unreachableList,
    results
  };

  // 确保 logs 目录
  try { fs.mkdirSync(LOGS_DIR, { recursive: true }); } catch {}

  // 原子写
  try {
    const tmp = HEALTH_FILE + '.tmp';
    fs.writeFileSync(tmp, JSON.stringify(snapshot, null, 2), 'utf8');
    fs.renameSync(tmp, HEALTH_FILE);
  } catch {}

  safeExit();
}

if (require.main === module) main();

module.exports = { probeMcp, commandPlausible };
`;

function patchHookFile() {
  if (!fs.existsSync(HOOKS_DIR)) {
    console.error('[patch-phase1-T1.2] hooks 目录不存在:', HOOKS_DIR);
    process.exit(1);
  }

  if (fs.existsSync(HOOK_TARGET)) {
    const current = fs.readFileSync(HOOK_TARGET, 'utf8');
    if (current.includes(SENTINEL) && current === HOOK_CONTENT) {
      console.log('[patch-phase1-T1.2] hook 已落地且内容一致，跳过 hook 写入');
      return 'skipped';
    }
    const bak = HOOK_TARGET + '.bak.phase1-t1.2';
    fs.copyFileSync(HOOK_TARGET, bak);
    console.log('[patch-phase1-T1.2] 已备份旧 hook:', bak);
  }

  const tmp = HOOK_TARGET + '.tmp';
  fs.writeFileSync(tmp, HOOK_CONTENT, 'utf8');
  fs.renameSync(tmp, HOOK_TARGET);
  console.log('[patch-phase1-T1.2] 已写入 hook:', HOOK_TARGET);

  // 语法自检 (只检查能否被 Node 解析，不执行 main)
  try {
    const { execFileSync } = require('child_process');
    execFileSync(process.execPath, ['--check', HOOK_TARGET], { stdio: 'pipe' });
    console.log('[patch-phase1-T1.2] hook 语法自检 PASS (node --check)');
  } catch (e) {
    console.error('[patch-phase1-T1.2] hook 语法自检失败:', (e.stderr || e.message || '').toString().slice(0, 500));
    process.exit(3);
  }
  return 'written';
}

function patchSettings() {
  if (!fs.existsSync(SETTINGS_FILE)) {
    console.error('[patch-phase1-T1.2] settings.json 不存在:', SETTINGS_FILE);
    process.exit(4);
  }

  const before = fs.readFileSync(SETTINGS_FILE, 'utf8');
  const settings = JSON.parse(before);

  if (!settings.hooks) settings.hooks = {};
  if (!Array.isArray(settings.hooks.UserPromptSubmit)) settings.hooks.UserPromptSubmit = [];

  // 幂等: 检查是否已注册
  const alreadyRegistered = settings.hooks.UserPromptSubmit.some(group =>
    Array.isArray(group.hooks) && group.hooks.some(h => h.command === HOOK_CMD)
  );
  if (alreadyRegistered) {
    console.log('[patch-phase1-T1.2] settings.json 已注册，跳过');
    return 'skipped';
  }

  // 备份原 settings.json
  fs.copyFileSync(SETTINGS_FILE, SETTINGS_BAK);
  console.log('[patch-phase1-T1.2] 已备份 settings.json:', SETTINGS_BAK);

  // 追加新 hook group (独立 group，不影响既有 hook 顺序)
  settings.hooks.UserPromptSubmit.push({
    hooks: [
      {
        type: 'command',
        command: HOOK_CMD,
        timeout: 3000
      }
    ]
  });

  // 原子写
  const tmp = SETTINGS_FILE + '.tmp';
  fs.writeFileSync(tmp, JSON.stringify(settings, null, 2), 'utf8');

  // 验证写出的 JSON 可解析
  try {
    JSON.parse(fs.readFileSync(tmp, 'utf8'));
  } catch (e) {
    fs.unlinkSync(tmp);
    console.error('[patch-phase1-T1.2] 写出的 settings.json 无法解析，中止');
    process.exit(5);
  }

  fs.renameSync(tmp, SETTINGS_FILE);
  console.log('[patch-phase1-T1.2] settings.json 已更新');
  return 'updated';
}

function main() {
  const hookResult = patchHookFile();
  const settingsResult = patchSettings();

  console.log('');
  console.log('[patch-phase1-T1.2] sentinel:', SENTINEL);
  console.log('[patch-phase1-T1.2] hook:', hookResult);
  console.log('[patch-phase1-T1.2] settings:', settingsResult);
  console.log('[patch-phase1-T1.2] 完成。');
  console.log('');
  console.log('验证:');
  console.log('  1. 下次 UserPromptSubmit 触发，生成 ~/.claude/logs/mcp-health-<today>.json');
  console.log('  2. 查看: cat ~/.claude/logs/mcp-health-$(date -u +%Y-%m-%d).json');
  console.log('');
  console.log('紧急回滚:');
  console.log('  方式 1: cp ' + SETTINGS_BAK + ' ' + SETTINGS_FILE);
  console.log('  方式 2: 在 ' + path.join(CLAUDE_ROOT, '.bookworm-features.json') + ' 设 {"mcp_probe": false}');
  process.exit(0);
}

main();