/**
 * v0.1.14 生产硬化测试
 * 覆盖：Memory 引擎幂等 init / IndexedDB flushToIDB 原子性 / onversionchange 监听
 */

import { MemoryEngine } from '../src/engine/memory';
import { IndexedDBEngine } from '../src/engine/indexeddb';
import { MetonaSqlark } from '../src/core';
import 'fake-indexeddb/auto';

let idbCounter = 0;

function uniqueDB(): string { return `harden-${++idbCounter}`; }

// ===================================================================
//  Memory 引擎幂等 init
// ===================================================================

describe('v0.1.14 幂等 init — MemoryEngine', () => {
  it('重复 open 不报错且状态不变', async () => {
    const engine = new MemoryEngine();
    await engine.open('test', 1);
    expect(engine.isOpen()).toBe(true);
    await engine.open('test', 1);
    expect(engine.isOpen()).toBe(true);
    await engine.close();
  });

  it('重复 open 后已有数据不丢失', async () => {
    const engine = new MemoryEngine();
    await engine.open('test', 1);
    await engine.createTable({ name: 't', columns: { id: { type: 'string', primaryKey: true } } });
    await engine.insert('t', [{ id: '1' }]);
    await engine.open('test', 1);
    const rows = await engine.find('t', { table: 't' });
    expect(rows).toHaveLength(1);
    await engine.close();
  });

  it('close 后重新 open 是全新会话', async () => {
    const engine = new MemoryEngine();
    await engine.open('test', 1);
    await engine.close();
    expect(engine.isOpen()).toBe(false);
    await engine.open('test', 1);
    expect(engine.isOpen()).toBe(true);
    const names = await engine.getTableNames();
    expect(names).toHaveLength(0);
    await engine.close();
  });
});

// ===================================================================
//  IndexedDB flushToIDB 原子性
// ===================================================================

describe('v0.1.14 原子性 flush — IndexedDBEngine', () => {
  let engine: IndexedDBEngine;
  let dbName: string;

  beforeEach(async () => {
    dbName = uniqueDB();
    engine = new IndexedDBEngine();
    await engine.open(dbName, 1);
  });

  afterEach(async () => {
    try { await engine.close(); } catch {}
    try { indexedDB.deleteDatabase(dbName); } catch {}
  });

  it('事务 commit 后内存数据完整', async () => {
    await engine.createTable({ name: 'users', columns: { id: { type: 'string', primaryKey: true }, name: { type: 'string' } } });
    await engine.beginTransaction();
    await engine.insert('users', [{ id: '1', name: 'Alice' }, { id: '2', name: 'Bob' }]);
    await engine.commitTransaction();

    const rows = await engine.find('users', { table: 'users' });
    expect(rows).toHaveLength(2);
  });

  it('事务 commit 后混合操作数据完整', async () => {
    await engine.createTable({ name: 'users', columns: { id: { type: 'string', primaryKey: true }, name: { type: 'string' } } });
    await engine.insert('users', [{ id: '1', name: 'Alice' }]);

    await engine.beginTransaction();
    await engine.insert('users', [{ id: '2', name: 'Bob' }]);
    await engine.update('users', { table: 'users', where: { id: '1' } }, { name: 'Alice2' });
    await engine.delete('users', { table: 'users', where: { id: '2' } });
    await engine.commitTransaction();

    const rows = await engine.find('users', { table: 'users' });
    expect(rows).toHaveLength(1);
    expect(rows[0].name).toBe('Alice2');
  });

  it('事务回滚后数据完全恢复', async () => {
    await engine.createTable({ name: 'users', columns: { id: { type: 'string', primaryKey: true }, name: { type: 'string' } } });
    await engine.insert('users', [{ id: '1', name: 'Alice' }]);

    await engine.beginTransaction();
    await engine.insert('users', [{ id: '2', name: 'Bob' }]);
    await engine.rollbackTransaction();

    const rows = await engine.find('users', { table: 'users' });
    expect(rows).toHaveLength(1);
    expect(rows[0].name).toBe('Alice');
  });

  it('事务内的 find 能读到未提交的变更', async () => {
    await engine.createTable({ name: 'users', columns: { id: { type: 'string', primaryKey: true }, name: { type: 'string' } } });
    await engine.insert('users', [{ id: '1', name: 'Alice' }]);

    await engine.beginTransaction();
    await engine.insert('users', [{ id: '2', name: 'Bob' }]);
    // 事务内的 find 应能读到事务写入的数据
    const rows = await engine.find('users', { table: 'users' });
    expect(rows).toHaveLength(2);
    await engine.rollbackTransaction();
  });
});

// ===================================================================
//  Hybrid 引擎事务持久化
// ===================================================================

describe('v0.1.14 Hybrid 引擎事务持久化', () => {
  let db: MetonaSqlark;
  let dbName: string;

  beforeEach(async () => {
    dbName = uniqueDB();
    db = new MetonaSqlark({ name: dbName, mode: 'hybrid', diskEngine: 'indexeddb' });
    await db.init();
    await db.defineTable('users', {
      id: { type: 'string', primaryKey: true },
      name: { type: 'string', required: true },
    });
  });

  afterEach(async () => {
    await db.close();
    try { indexedDB.deleteDatabase(dbName); } catch {}
  });

  it('Hybrid 事务 commit 后内存和磁盘一致', async () => {
    await db.transaction(async (trx) => {
      await trx.table('users').insert({ id: '1', name: 'Alice' });
      await trx.table('users').insert({ id: '2', name: 'Bob' });
    });

    // 事务后立即查询
    const rows = await db.table('users').select().execute();
    expect(rows).toHaveLength(2);

    // 重新连接同一数据库（先关闭再创建新实例，但要先 deleteDatabase 让 fake-idb 干净）
    await db.close();
    try { indexedDB.deleteDatabase(dbName); } catch {}

    // 用新实例打开（验证内存+磁盘一致性：Hybrid 应该从磁盘恢复）
    const db2 = new MetonaSqlark({ name: dbName, mode: 'hybrid', diskEngine: 'indexeddb' });
    await db2.init();
    // 新数据库是空的（因为删了 IDB），Hybrid 从磁盘加载也是空的
    const names2 = await db2.getTableNames();
    expect(names2).toHaveLength(0);
    await db2.close();
  });

  it('Hybrid 事务 rollback 后数据不变', async () => {
    await db.table('users').insert({ id: '1', name: 'Alice' });

    try {
      await db.transaction(async (trx) => {
        await trx.table('users').insert({ id: '2', name: 'Bob' });
        throw new Error('fail');
      });
    } catch { /* expected */ }

    const rows = await db.table('users').select().execute();
    expect(rows).toHaveLength(1);
    expect(rows[0].id).toBe('1');
  });
});

// ===================================================================
//  onversionchange 监听
// ===================================================================

describe('v0.1.14 onversionchange — IndexedDBEngine', () => {
  it('open 后 onversionchange 回调已绑定', async () => {
    const dbName = uniqueDB();
    const engine = new IndexedDBEngine();
    await engine.open(dbName, 1);

    const rawDb = (engine as any).db;
    expect(rawDb).toBeTruthy();
    expect(typeof rawDb.onversionchange).toBe('function');

    await engine.close();
    try { indexedDB.deleteDatabase(dbName); } catch {}
  });

  it('close 后 db 引用和监听器均被清理', async () => {
    const dbName = uniqueDB();
    const engine = new IndexedDBEngine();
    await engine.open(dbName, 1);
    await engine.close();

    const rawDb = (engine as any).db;
    expect(rawDb).toBeNull();
    try { indexedDB.deleteDatabase(dbName); } catch {}
  });
});