/**
 * File Guard 单元测试（P1-14 测试基线）
 * 覆盖：路径遍历防护、前缀碰撞、MEMORY.md 保护、glob 匹配、编码检测
 */

import { describe, it, expect, beforeAll, afterAll } from 'vitest';
import { mkdtempSync, rmSync, writeFileSync, mkdirSync } from 'fs';
import { tmpdir } from 'os';
import { join } from 'path';
import {
  isPathWithinWorkspace,
  isProtectedWorkspaceFile,
  safeResolvePath,
  matchGlob,
  matchAnyGlob,
  commandTouchesProtectedFile,
  decodeBufferWithDetection,
} from '../file-guard';

describe('isPathWithinWorkspace', () => {
  const ws = join(tmpdir(), 'metona-test-ws');

  beforeAll(() => {
    mkdirSync(ws, { recursive: true });
  });

  it('工作空间内的相对路径通过', () => {
    expect(isPathWithinWorkspace('src/main.ts', ws)).toBe(true);
  });

  it('工作空间内的绝对路径通过', () => {
    expect(isPathWithinWorkspace(join(ws, 'src/main.ts'), ws)).toBe(true);
  });

  it('工作空间根目录本身通过', () => {
    expect(isPathWithinWorkspace('.', ws)).toBe(true);
  });

  it('路径遍历（../）被拒绝', () => {
    expect(isPathWithinWorkspace('../etc/passwd', ws)).toBe(false);
  });

  it('多层遍历（../../..）被拒绝', () => {
    expect(isPathWithinWorkspace('../../../etc/passwd', ws)).toBe(false);
  });

  it('前缀碰撞不误判（/app-evil 不在 /app 内）', () => {
    const parent = join(tmpdir(), 'metona-prefix-app');
    mkdirSync(parent, { recursive: true });
    expect(isPathWithinWorkspace(join(tmpdir(), 'metona-prefix-app-evil/x'), parent)).toBe(false);
  });

  it('绝对路径指向工作空间外被拒绝', () => {
    expect(isPathWithinWorkspace('C:\\Windows\\System32\\cmd.exe', ws)).toBe(false);
  });
});

describe('isProtectedWorkspaceFile / safeResolvePath', () => {
  const ws = join(tmpdir(), 'metona-test-protect');

  beforeAll(() => {
    mkdirSync(join(ws, 'sub'), { recursive: true });
  });

  it('工作空间根目录的 MEMORY.md 受保护', () => {
    expect(isProtectedWorkspaceFile('MEMORY.md', ws)).toBe(true);
  });

  it('子目录的 MEMORY.md 不受保护', () => {
    expect(isProtectedWorkspaceFile(join('sub', 'MEMORY.md'), ws)).toBe(false);
  });

  it('safeResolvePath 拒绝越界路径并抛错', () => {
    expect(() => safeResolvePath('../outside.txt', ws)).toThrow(/Path traversal/);
  });

  it('safeResolvePath 拒绝根目录 MEMORY.md 并抛错', () => {
    expect(() => safeResolvePath('MEMORY.md', ws)).toThrow(/MEMORY.md/);
  });

  it('safeResolvePath 正常解析工作空间内路径', () => {
    const resolved = safeResolvePath('src/a.ts', ws);
    expect(resolved).toBe(join(ws, 'src/a.ts'));
  });
});

describe('commandTouchesProtectedFile', () => {
  it('裸引用 MEMORY.md 被拦截', () => {
    expect(commandTouchesProtectedFile('cat MEMORY.md')).toBe(true);
  });

  it('子目录 MEMORY.md 不被拦截', () => {
    expect(commandTouchesProtectedFile('cat sub/MEMORY.md')).toBe(false);
    expect(commandTouchesProtectedFile('cat sub\\MEMORY.md')).toBe(false);
  });

  it('管道/分号后的 MEMORY.md 被拦截', () => {
    expect(commandTouchesProtectedFile('echo x | cat MEMORY.md; rm file')).toBe(true);
  });

  it('无关命令不误判', () => {
    expect(commandTouchesProtectedFile('npm run test')).toBe(false);
    expect(commandTouchesProtectedFile('git status')).toBe(false);
  });
});

describe('matchGlob / matchAnyGlob', () => {
  it('单 glob 匹配', () => {
    expect(matchGlob('main.ts', '*.ts')).toBe(true);
    expect(matchGlob('main.js', '*.ts')).toBe(false);
  });

  it('? 单字符匹配', () => {
    expect(matchGlob('test1.js', 'test?.js')).toBe(true);
    expect(matchGlob('test12.js', 'test?.js')).toBe(false);
  });

  it('逗号分隔多 glob 任一匹配', () => {
    expect(matchAnyGlob('a.ts', '*.ts,*.js,*.tsx')).toBe(true);
    expect(matchAnyGlob('a.jsx', '*.ts,*.js,*.tsx')).toBe(false);
  });

  it('空 glob 字符串匹配所有', () => {
    expect(matchAnyGlob('anything.txt', '')).toBe(true);
  });
});

describe('decodeBufferWithDetection', () => {
  it('UTF-8 无 BOM 正确解码', () => {
    const buf = Buffer.from('你好 world', 'utf-8');
    const { content, encoding } = decodeBufferWithDetection(buf);
    expect(content).toBe('你好 world');
    expect(encoding).toBe('utf-8');
  });

  it('UTF-8 BOM 被剥离并识别', () => {
    const body = Buffer.from('hello', 'utf-8');
    const buf = Buffer.concat([Buffer.from([0xef, 0xbb, 0xbf]), body]);
    const { content, encoding } = decodeBufferWithDetection(buf);
    expect(content).toBe('hello');
    expect(encoding).toBe('utf-8-bom');
  });

  it('UTF-16 LE BOM 正确解码', () => {
    const body = '你好';
    const buf = Buffer.concat([Buffer.from([0xff, 0xfe]), Buffer.from(body, 'utf16le')]);
    const { content, encoding } = decodeBufferWithDetection(buf);
    expect(content).toBe(body);
    expect(encoding).toBe('utf-16le');
  });

  it('UTF-16 BE BOM 正确解码（字节交换）', () => {
    const body = '你好';
    const le = Buffer.from(body, 'utf16le');
    const be = Buffer.from(le);
    be.swap16();
    const buf = Buffer.concat([Buffer.from([0xfe, 0xff]), be]);
    const { content, encoding } = decodeBufferWithDetection(buf);
    expect(content).toBe(body);
    expect(encoding).toBe('utf-16be');
  });

  it('空 Buffer 返回空内容', () => {
    const { content, encoding } = decodeBufferWithDetection(Buffer.alloc(0));
    expect(content).toBe('');
    expect(encoding).toBe('utf-8');
  });
});

describe('workspace 文件读取场景（临时目录）', () => {
  let ws: string;

  beforeAll(() => {
    ws = mkdtempSync(join(tmpdir(), 'metona-guard-'));
    writeFileSync(join(ws, 'file.txt'), 'content', 'utf-8');
  });

  afterAll(() => {
    rmSync(ws, { recursive: true, force: true });
  });

  it('工作空间内文件路径通过校验', () => {
    expect(isPathWithinWorkspace('file.txt', ws)).toBe(true);
    expect(isPathWithinWorkspace(join(ws, 'file.txt'), ws)).toBe(true);
  });
});