#!/usr/bin/env node
/**
 * 多项目上下文隔离器 (v5.9)
 *
 * 为不同工作目录 (cwd) 提供隔离的状态文件路径，
 * 防止项目 A 的上下文/权重污染项目 B 的路由。
 *
 * 隔离文件:
 *   - context-state.json     → context-state-{hash}.json
 *   - fusion-weights.json    → fusion-weights-{hash}.json
 *   - route-weights.json     → route-weights-{hash}.json
 *
 * 非隔离 (全局共享):
 *   - route-feedback.jsonl   (全局学习语料)
 *   - skill-outcome.jsonl    (全局观测)
 *   - skills-index.json      (技能定义)
 *
 * 用法:
 *   const { getIsolatedPath } = require('./project-isolator.js');
 *   const stateFile = getIsolatedPath('context-state.json', cwd);
 */

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

const detectClaudeRoot = () => require('./paths.config.js').PATHS.root;

const ROOT = detectClaudeRoot();
const DEBUG_DIR = path.join(ROOT, 'debug');

// 需要隔离的文件名列表
const ISOLATED_FILES = new Set([
  'context-state.json',
  'fusion-weights.json',
  'route-weights.json',
  'session-memory.json',  // 防止跨项目会话偏好污染
]);

/**
 * 为 cwd 生成短哈希 (6 字符)
 * @param {string} cwd - 工作目录
 * @returns {string} 6 位 hex 哈希
 */
function cwdHash(cwd) {
  if (!cwd) return 'global';
  const normalized = cwd.replace(/\\/g, '/').replace(/\/+$/, '').toLowerCase();
  return crypto.createHash('md5').update(normalized).digest('hex').slice(0, 6);
}

/**
 * 获取隔离后的文件路径
 * @param {string} filename - 原始文件名 (如 'context-state.json')
 * @param {string} [cwd] - 工作目录 (null/undefined 使用全局路径)
 * @returns {string} 隔离后的完整路径
 */
function getIsolatedPath(filename, cwd) {
  if (!cwd || !ISOLATED_FILES.has(filename)) {
    return path.join(DEBUG_DIR, filename);
  }
  const hash = cwdHash(cwd);
  const ext = path.extname(filename);
  const base = path.basename(filename, ext);
  return path.join(DEBUG_DIR, `${base}-${hash}${ext}`);
}

/**
 * 列出某个基础文件的所有隔离实例
 * @param {string} filename - 原始文件名
 * @returns {Array<{path: string, hash: string, mtime: Date}>}
 */
function listInstances(filename) {
  const ext = path.extname(filename);
  const base = path.basename(filename, ext);
  const pattern = new RegExp(`^${base}-([a-f0-9]{6})${ext.replace('.', '\\.')}$`);

  try {
    return fs.readdirSync(DEBUG_DIR)
      .filter(f => pattern.test(f))
      .map(f => {
        const match = f.match(pattern);
        const fullPath = path.join(DEBUG_DIR, f);
        const stat = fs.statSync(fullPath);
        return { path: fullPath, hash: match[1], mtime: stat.mtime };
      })
      .sort((a, b) => b.mtime - a.mtime);
  } catch {
    return [];
  }
}

/**
 * 清理过期隔离文件 (超过 30 天未修改)
 * @returns {number} 清理数量
 */
function cleanStale(maxAgeDays = 30) {
  const cutoff = Date.now() - maxAgeDays * 86400000;
  let cleaned = 0;
  for (const filename of ISOLATED_FILES) {
    for (const inst of listInstances(filename)) {
      if (inst.mtime.getTime() < cutoff) {
        try { fs.unlinkSync(inst.path); cleaned++; } catch {}
      }
    }
  }
  return cleaned;
}

// 模块导出
if (typeof module !== 'undefined') {
  module.exports = {
    cwdHash, getIsolatedPath, listInstances, cleanStale,
    ISOLATED_FILES, DEBUG_DIR,
  };
}

// CLI 入口
if (require.main === module) {
  console.log('=== 多项目隔离器 ===');

  // 列出所有隔离实例
  for (const filename of ISOLATED_FILES) {
    const instances = listInstances(filename);
    console.log(`\n${filename}: ${instances.length} 个实例`);
    for (const inst of instances) {
      console.log(`  [${inst.hash}] ${inst.mtime.toISOString().slice(0, 19)}`);
    }
  }

  // 测试
  const testCwds = [
    'C:\\Users\\home\\project-a',
    'C:\\Users\\home\\project-b',
    '/opt/xianyuzhushou',
  ];
  console.log('\n测试路径映射:');
  for (const cwd of testCwds) {
    const hash = cwdHash(cwd);
    console.log(`  ${cwd} → ${hash}`);
    console.log(`    context-state: ${path.basename(getIsolatedPath('context-state.json', cwd))}`);
  }
}