/**
 * MemoryEngine 测试
 */

import { MemoryEngine } from '../../src/engine/memory';
import { createSchema } from '../../src/table/schema';

describe('MemoryEngine', () => {
  let engine: MemoryEngine;

  const userSchema = createSchema('users', {
    id: { type: 'string', primaryKey: true },
    name: { type: 'string', required: true },
    age: { type: 'number', default: 0 },
    email: { type: 'string', unique: true },
  });

  beforeEach(async () => {
    engine = new MemoryEngine();
    await engine.open('test-db', 1);
  });

  afterEach(async () => {
    await engine.close();
  });

  // ---- 生命周期 ----

  describe('open/close', () => {
    it('打开后 isOpen 返回 true', () => {
      expect(engine.isOpen()).toBe(true);
    });

    it('关闭后 isOpen 返回 false', async () => {
      await engine.close();
      expect(engine.isOpen()).toBe(false);
    });
  });

  // ---- 表管理 ----

  describe('表管理', () => {
    it('创建表', async () => {
      await engine.createTable(userSchema);
      expect(await engine.hasTable('users')).toBe(true);
    });

    it('重复创建表抛出错误', async () => {
      await engine.createTable(userSchema);
      await expect(engine.createTable(userSchema)).rejects.toThrow('already exists');
    });

    it('获取所有表名', async () => {
      await engine.createTable(userSchema);
      const names = await engine.getTableNames();
      expect(names).toContain('users');
    });

    it('删除表', async () => {
      await engine.createTable(userSchema);
      await engine.dropTable('users');
      expect(await engine.hasTable('users')).toBe(false);
    });
  });

  // ---- CRUD ----

  describe('插入', () => {
    beforeEach(async () => {
      await engine.createTable(userSchema);
    });

    it('插入单行', async () => {
      const pks = await engine.insert('users', [
        { id: '1', name: 'Alice', age: 30, email: 'alice@test.com' },
      ]);
      expect(pks).toEqual(['1']);
    });

    it('插入多行', async () => {
      const pks = await engine.insert('users', [
        { id: '1', name: 'Alice', age: 30, email: 'alice@test.com' },
        { id: '2', name: 'Bob', age: 25, email: 'bob@test.com' },
      ]);
      expect(pks).toEqual(['1', '2']);
    });

    it('重复主键抛出错误', async () => {
      await engine.insert('users', [{ id: '1', name: 'Alice', email: 'a@t.com' }]);
      await expect(
        engine.insert('users', [{ id: '1', name: 'Duplicate', email: 'd@t.com' }]),
      ).rejects.toThrow('Duplicate');
    });

    it('唯一约束冲突', async () => {
      await engine.insert('users', [{ id: '1', name: 'Alice', email: 'same@test.com' }]);
      await expect(
        engine.insert('users', [{ id: '2', name: 'Bob', email: 'same@test.com' }]),
      ).rejects.toThrow('Unique constraint');
    });

    it('必填字段缺失', async () => {
      await expect(
        engine.insert('users', [{ id: '1' }]),
      ).rejects.toThrow('required');
    });

    it('默认值填充', async () => {
      await engine.insert('users', [{ id: '1', name: 'Alice', email: 'a@t.com' }]);
      const rows = await engine.find('users', { table: 'users' });
      expect(rows[0].age).toBe(0);
    });

    it('类型错误', async () => {
      await expect(
        engine.insert('users', [{ id: '1', name: 'Alice', age: 'not-a-number', email: 'a@t.com' }]),
      ).rejects.toThrow('expects number');
    });
  });

  // ---- 查询 ----

  describe('查询', () => {
    beforeEach(async () => {
      await engine.createTable(userSchema);
      await engine.insert('users', [
        { id: '1', name: 'Alice', age: 30, email: 'alice@test.com' },
        { id: '2', name: 'Bob', age: 25, email: 'bob@test.com' },
        { id: '3', name: 'Charlie', age: 35, email: 'charlie@test.com' },
      ]);
    });

    it('查询所有行', async () => {
      const rows = await engine.find('users', { table: 'users' });
      expect(rows).toHaveLength(3);
    });

    it('WHERE $gt', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        where: { age: { $gt: 28 } },
      });
      expect(rows).toHaveLength(2);
      expect(rows.map((r) => r.id).sort()).toEqual(['1', '3']);
    });

    it('WHERE $eq', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        where: { name: 'Alice' },
      });
      expect(rows).toHaveLength(1);
      expect(rows[0].id).toBe('1');
    });

    it('WHERE $in', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        where: { age: { $in: [25, 35] } },
      });
      expect(rows).toHaveLength(2);
    });

    it('WHERE $like', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        where: { name: { $like: 'A%' } },
      });
      expect(rows).toHaveLength(1);
      expect(rows[0].name).toBe('Alice');
    });

    it('ORDER BY asc', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        orderBy: [{ column: 'age', direction: 'asc' }],
      });
      expect(rows.map((r) => r.age)).toEqual([25, 30, 35]);
    });

    it('ORDER BY desc', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        orderBy: [{ column: 'age', direction: 'desc' }],
      });
      expect(rows.map((r) => r.age)).toEqual([35, 30, 25]);
    });

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

    it('OFFSET', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        orderBy: [{ column: 'id', direction: 'asc' }],
        offset: 1,
        limit: 1,
      });
      expect(rows).toHaveLength(1);
      expect(rows[0].id).toBe('2');
    });

    it('列选择', async () => {
      const rows = await engine.find('users', {
        table: 'users',
        columns: ['id', 'name'],
        where: { id: '1' },
      });
      expect(Object.keys(rows[0]).sort()).toEqual(['id', 'name']);
    });
  });

  // ---- 更新 ----

  describe('更新', () => {
    beforeEach(async () => {
      await engine.createTable(userSchema);
      await engine.insert('users', [
        { id: '1', name: 'Alice', age: 30, email: 'alice@test.com' },
        { id: '2', name: 'Bob', age: 25, email: 'bob@test.com' },
      ]);
    });

    it('更新单行', async () => {
      const count = await engine.update('users',
        { table: 'users', where: { id: '1' } },
        { age: 31 },
      );
      expect(count).toBe(1);
      const rows = await engine.find('users', { table: 'users', where: { id: '1' } });
      expect(rows[0].age).toBe(31);
    });

    it('更新所有行', async () => {
      const count = await engine.update('users',
        { table: 'users' },
        { age: 100 },
      );
      expect(count).toBe(2);
    });
  });

  // ---- 删除 ----

  describe('删除', () => {
    beforeEach(async () => {
      await engine.createTable(userSchema);
      await engine.insert('users', [
        { id: '1', name: 'Alice', age: 30, email: 'alice@test.com' },
        { id: '2', name: 'Bob', age: 25, email: 'bob@test.com' },
      ]);
    });

    it('条件删除', async () => {
      const count = await engine.delete('users', { table: 'users', where: { id: '1' } });
      expect(count).toBe(1);
      const rows = await engine.find('users', { table: 'users' });
      expect(rows).toHaveLength(1);
    });

    it('清空表', async () => {
      await engine.clear('users');
      const count = await engine.count('users');
      expect(count).toBe(0);
    });
  });
});