#!/usr/bin/env node
/**
 * PreToolUse Hook: NDA 读取防护
 * 匹配器: Read|Glob|Grep
 * 阻止 AI 读取 Bookworm 系统配置文件，防止通过工具调用泄露架构信息。
 *
 * 退出码: 0=放行, 2=阻断(deny)
 * 激活条件: 仅在 Portable 发行版的 settings.json 中注册
 */
'use strict';

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

const CLAUDE_ROOT = require('./lib/root.js');

// 安全日志 (fail-open)
let logSecurityEvent = () => {};
try {
  logSecurityEvent = require('./lib/security-log.js').logSecurityEvent;
} catch {}

// --- 路径规范化 (对齐 block-sensitive-reads 的逻辑) ---
function normalizePath(fp) {
  if (!fp) return '';
  fp = fp.trim();
  let resolved = path.resolve(fp);
  try { resolved = fs.realpathSync(resolved); } catch {}
  return resolved.replace(/\\/g, '/')
    .replace(/\.+$/, '')
    .replace(/::?\$DATA$/i, '');
}

// --- 白名单: 用户自己的数据，AI 需要访问 ---
const WHITELIST = [
  /[\/]\.claude[\/]projects([\/]|$)/i,    // 项目级 CLAUDE.md (用户项目配置)
  /[\/]\.claude[\/]memory([\/]|$)/i,      // 用户记忆文件
];

// --- 黑名单: 系统核心文件/目录 ---
const BLACKLIST_PATHS = [
  // 精确文件
  { pattern: /[\/]\.claude[\/]CLAUDE\.md$/i,              reason: '系统配置' },
  { pattern: /[\/]\.claude[\/]settings\.json$/i,          reason: '系统配置' },
  { pattern: /[\/]\.claude[\/]settings\.local\.json$/i,   reason: '系统配置' },
  { pattern: /[\/]\.claude[\/]stats-compiled\.json$/i,    reason: '系统数据' },
  { pattern: /[\/]\.claude[\/]MEMORY\.md$/i,              reason: '系统索引' },
  // 目录级
  { pattern: /[\/]\.claude[\/]skills[\/]/i,               reason: '系统模块' },
  { pattern: /[\/]\.claude[\/]agents[\/]/i,               reason: '系统模块' },
  { pattern: /[\/]\.claude[\/]hooks[\/]/i,                reason: '系统模块' },
  { pattern: /[\/]\.claude[\/]scripts[\/]/i,              reason: '系统脚本' },
  { pattern: /[\/]\.claude[\/]rules[\/]/i,                reason: '系统规则' },
  { pattern: /[\/]\.claude[\/]constitution[\/]/i,         reason: '系统规则' },
  { pattern: /[\/]\.claude[\/]docs[\/]/i,                 reason: '系统文档' },
  { pattern: /[\/]\.claude[\/]debug[\/]/i,                reason: '系统日志' },
  { pattern: /[\/]\.claude[\/]templates[\/]/i,            reason: '系统模板' },
];

// --- Glob 模式黑名单 (匹配 Glob 工具的 pattern 参数) ---
const GLOB_BLACKLIST = [
  /\.claude/i,
  /skills[\/\\]/i,
  /agents[\/\\]/i,
  /hooks[\/\\]/i,
  /CLAUDE\.md/i,
  /settings\.json/i,
  /SKILL\.md/i,
];

// 拒绝消息 (不暴露防护机制)
const DENY_MSG = '[系统] 该路径属于系统内部区域，无法访问。请直接描述您需要完成的任务，我来帮您。';

/**
 * 检查路径是否命中黑名单
 * @returns {string|null} 命中原因，null 表示放行
 */
function checkPath(normalizedPath) {
  if (!normalizedPath) return null;

  // 白名单优先
  for (const wp of WHITELIST) {
    if (wp.test(normalizedPath)) return null;
  }

  // 黑名单
  for (const { pattern, reason } of BLACKLIST_PATHS) {
    if (pattern.test(normalizedPath)) return reason;
  }

  // 兜底: 任何 .claude/ 下未白名单的路径
  if (/[\/]\.claude[\/]/.test(normalizedPath)) {
    // 排除 .claude/projects/ 和 .claude/memory/ (已在白名单)
    return '系统目录';
  }

  return null;
}

/**
 * 检查 Glob 的 pattern 参数
 */
function checkGlobPattern(pattern) {
  if (!pattern) return null;
  for (const bp of GLOB_BLACKLIST) {
    if (bp.test(pattern)) return '系统模式搜索';
  }
  return null;
}

/**
 * 可导出的统一检查入口 (供 dispatcher 或测试调用)
 */
function checkInput(input) {
  const toolName = (input.tool_name || '').toLowerCase();
  const ti = input.tool_input || {};

  // --- Read ---
  if (toolName === 'read') {
    const fp = normalizePath(ti.file_path || ti.filePath || '');
    const reason = checkPath(fp);
    if (reason) return { decision: 'deny', reason, path: ti.file_path };
  }

  // --- Glob ---
  if (toolName === 'glob') {
    // 检查搜索目录
    const searchPath = normalizePath(ti.path || '');
    const pathReason = checkPath(searchPath);
    if (pathReason) return { decision: 'deny', reason: pathReason, path: ti.path };

    // 检查 glob pattern
    const patternReason = checkGlobPattern(ti.pattern || '');
    if (patternReason) return { decision: 'deny', reason: patternReason, path: ti.pattern };
  }

  // --- Grep ---
  if (toolName === 'grep') {
    const searchPath = normalizePath(ti.path || '');
    const reason = checkPath(searchPath);
    if (reason) return { decision: 'deny', reason, path: ti.path };
  }

  return null; // 放行
}

// --- 主流程 ---
function main() {
  readStdin({ maxSize: 512 * 1024 }).then(input => {
    const result = checkInput(input);

    if (result) {
      logSecurityEvent('nda-deny', 'nda-read-guard', result.reason, result.path || '');
      process.stderr.write(JSON.stringify({
        hookSpecificOutput: { permissionDecision: 'deny' },
        systemMessage: DENY_MSG,
      }));
      process.exit(2);
      return;
    }

    process.exit(0);
  }).catch(() => {
    // fail-open: 解析异常时放行 (不阻断用户正常工作)
    process.exit(0);
  });
}

if (typeof module !== 'undefined') {
  module.exports = { checkInput, checkPath, checkGlobPattern, normalizePath };
}

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