/**
 * OPFS 不可用时的错误必须"可操作"
 *
 * 现场复现（v0.8.0 回归 review 发现）：用 file:// 直接打开站点演示页 → 切到 Aria
 * 引擎 → `navigator.storage.getDirectory()` 抛 SecurityError（Chromium 认为本地
 * 文件不适合 Web 应用访问）→ 引擎把它包成 `ARIA_OPEN_ERROR`，**cause 没往上带**，
 * 用户只看到 "Failed to open AriaEngine database" —— 既不知道是环境问题，
 * 也不知道该怎么办（实测：`isSecureContext` 仍是 true、API 也**存在**，
 * 只有真正调用才会发现；所以不能靠"API 是否存在"提前判断）。
 */
import { describe, it, expect, afterEach } from '@jest/globals';
import { OPFSBackend } from '../../src/engine/aria/store/opfs_backend';

const realNavigator = globalThis.navigator;

afterEach(() => {
  Object.defineProperty(globalThis, 'navigator', { value: realNavigator, configurable: true });
});

function stubStorage(storage: unknown): void {
  Object.defineProperty(globalThis, 'navigator', {
    value: { ...(realNavigator as object), storage },
    configurable: true,
  });
}

describe('OPFSBackend.open — 环境不可用时给可操作的错误', () => {
  it('navigator.storage 缺失（老浏览器 / 非安全上下文）→ ARIA_OPFS_UNAVAILABLE', async () => {
    stubStorage(undefined);
    const backend = new OPFSBackend();
    await expect(backend.open('demo')).rejects.toMatchObject({ code: 'ARIA_OPFS_UNAVAILABLE' });
    try {
      await backend.open('demo');
    } catch (error) {
      const message = (error as Error).message;
      expect(message).toContain('navigator.storage.getDirectory is missing');
      expect(message).toContain('http(s)');                 // 必须告诉用户怎么修
      expect(message).toContain('memory');
    }
  });

  it('getDirectory 抛 SecurityError（file:// 页面）→ 带原始 cause + 可操作建议', async () => {
    const security = new Error('It was determined that certain files are unsafe for access within a Web application');
    security.name = 'SecurityError';
    stubStorage({ getDirectory: async () => { throw security; } });

    const backend = new OPFSBackend();
    const error = await backend.open('demo').then(() => null, (e: unknown) => e) as
      (Error & { code?: string; cause?: unknown }) | null;
    expect(error).not.toBeNull();
    expect(error!.code).toBe('ARIA_OPFS_UNAVAILABLE');
    expect(error!.cause).toBe(security);                     // 原始错误必须保留（cause 非枚举，直接断言）
    expect(error!.message).toContain('SecurityError');
    expect(error!.message).toContain('file://');             // 点明最可能的成因
    expect(error!.message).toContain('http(s)');
    expect(error!.message).toContain('memory');
  });

  it('正常环境照旧可用（正控：不能把好环境也拒了）', async () => {
    const files = new Map<string, unknown>();
    const dirHandle = {
      async getFileHandle(name: string) {
        return { async createWritable() { return { async write() {}, async close() { files.set(name, 1); } }; } };
      },
      async getDirectoryHandle() { return dirHandle; },
      async removeEntry(name: string) { files.delete(name); },
      async *entries() { /* 无残留文件 */ },
    };
    stubStorage({ getDirectory: async () => dirHandle });
    const backend = new OPFSBackend();
    await backend.open('demo');
    expect(backend.isOpen()).toBe(true);
    await backend.close();
    expect(backend.isOpen()).toBe(false);
  });
});

describe('DatabaseError — 根因必须可通过标准 cause 取到', () => {
  it('第三个参数同时进 details 与 Error.cause（两者语义都成立）', async () => {
    const { DatabaseError } = await import('../../src/constants');
    const root = new Error('underlying failure');
    const err = new DatabaseError('wrapper message', 'WRAP_CODE', root);
    expect(err.code).toBe('WRAP_CODE');
    expect(err.details).toBe(root);        // 既有契约（文档示例打印 err.details）
    expect(err.cause).toBe(root);          // 标准错误链（v0.8.0 修复前恒为 undefined）
    expect(err.message).toBe('wrapper message');
    expect(err.name).toBe('DatabaseError');
    expect(err instanceof Error).toBe(true);
  });

  it('没有底层错误时不制造 cause（保持 undefined）', async () => {
    const { DatabaseError } = await import('../../src/constants');
    const err = new DatabaseError('plain', 'PLAIN_CODE');
    expect(err.details).toBeUndefined();
    expect(err.cause).toBeUndefined();
  });
});