/**
 * v0.5.1 — 维护语句 SQL 入口测试（EXPLAIN / ANALYZE / REINDEX / VACUUM / SAVEPOINT）
 *
 * 此前这些功能仅有引擎方法/executor 分支而无 SQL 入口（parser 无法解析），
 * 属"宣称存在但用户无法触发"的半成品。本次补齐 SQL 语法并验证真实执行。
 */
import { MetonaSqlark } from '../src/core';
import { parse } from '../src/sql/parser';
import { createSchema } from '../src/table/schema';
import 'fake-indexeddb/auto';

let dbCounter = 0;
function uniqueDB(): string {
  return `maint-${Date.now()}-${++dbCounter}-${Math.random().toString(36).slice(2, 8)}`;
}

describe('v0.5.1 — 维护语句解析', () => {
  it('EXPLAIN SELECT 解析为 ExplainStatement', () => {
    const stmt = parse('EXPLAIN SELECT * FROM users WHERE id = \'1\'');
    expect(stmt.type).toBe('EXPLAIN');
    expect((stmt as { query: { type: string } }).query.type).toBe('SELECT');
  });

  it('EXPLAIN 嵌套 EXPLAIN 拒绝', () => {
    expect(() => parse('EXPLAIN EXPLAIN SELECT 1')).toThrow('Nested EXPLAIN');
  });

  it('ANALYZE / ANALYZE TABLE 解析', () => {
    expect(parse('ANALYZE users')).toMatchObject({ type: 'ANALYZE', table: 'users' });
    expect(parse('ANALYZE TABLE users')).toMatchObject({ type: 'ANALYZE', table: 'users' });
  });

  it('REINDEX / VACUUM 解析', () => {
    expect(parse('REINDEX users')).toMatchObject({ type: 'REINDEX', table: 'users' });
    expect(parse('REINDEX TABLE users')).toMatchObject({ type: 'REINDEX', table: 'users' });
    expect(parse('VACUUM')).toMatchObject({ type: 'VACUUM' });
  });

  it('SAVEPOINT / ROLLBACK TO / RELEASE 解析', () => {
    expect(parse('SAVEPOINT sp1')).toMatchObject({ type: 'SAVEPOINT', name: 'sp1', action: 'SAVE' });
    expect(parse('ROLLBACK TO sp1')).toMatchObject({ type: 'SAVEPOINT', name: 'sp1', action: 'ROLLBACK' });
    expect(parse('ROLLBACK TO SAVEPOINT sp1')).toMatchObject({ type: 'SAVEPOINT', name: 'sp1', action: 'ROLLBACK' });
    expect(parse('RELEASE SAVEPOINT sp1')).toMatchObject({ type: 'SAVEPOINT', name: 'sp1', action: 'RELEASE' });
    expect(parse('RELEASE sp1')).toMatchObject({ type: 'SAVEPOINT', name: 'sp1', action: 'RELEASE' });
    // ROLLBACK [TRANSACTION] 保持原语义
    expect(parse('ROLLBACK')).toMatchObject({ type: 'ROLLBACK' });
    expect(parse('ROLLBACK TRANSACTION')).toMatchObject({ type: 'ROLLBACK' });
  });
});

describe('v0.5.1 — 维护语句执行（Aria 引擎）', () => {
  async function createAriaDb(): Promise<MetonaSqlark> {
    const db = new MetonaSqlark({
      name: uniqueDB(),
      mode: 'aria',
      diskEngine: 'indexeddb',
      aria: { checkpointInterval: 100000, walSyncMode: 'full' },
    });
    await db.init();
    await db.defineTable('users', {
      id: { type: 'string', primaryKey: true },
      name: { type: 'string', index: true },
      age: { type: 'number' },
    });
    await db.table('users').insertMany([
      { id: '1', name: 'Alice', age: 30 },
      { id: '2', name: 'Bob', age: 25 },
      { id: '3', name: 'Carol', age: 35 },
    ]);
    return db;
  }

  it('EXPLAIN SELECT 返回查询计划', async () => {
    const db = await createAriaDb();
    const plan = await db.query("EXPLAIN SELECT * FROM users WHERE id = '1'") as Record<string, unknown>;
    expect(plan.type).toBe('SELECT');
    expect(plan.table).toBe('users');
    expect(plan.estimatedRows).toBe(1);
    await db.close();
  });

  it('EXPLAIN UPDATE / DELETE 返回计划', async () => {
    const db = await createAriaDb();
    const planU = await db.query("EXPLAIN UPDATE users SET age = 31 WHERE id = '1'") as Record<string, unknown>;
    expect(planU.type).toBe('UPDATE');
    const planD = await db.query('EXPLAIN DELETE FROM users WHERE id = \'1\'') as Record<string, unknown>;
    expect(planD.type).toBe('DELETE');
    await db.close();
  });

  it('ANALYZE TABLE 收集统计信息', async () => {
    const db = await createAriaDb();
    const stats = await db.query('ANALYZE TABLE users') as Record<string, unknown>;
    expect(stats.rowCount).toBe(3);
    expect(stats.table).toBe('users');
    await db.close();
  });

  it('REINDEX TABLE 重建索引后索引查询正常', async () => {
    const db = await createAriaDb();
    const count = await db.query('REINDEX TABLE users') as number;
    expect(count).toBeGreaterThanOrEqual(0);
    const rows = await db.query("SELECT * FROM users WHERE name = 'Bob'") as Record<string, unknown>[];
    expect(rows).toHaveLength(1);
    await db.close();
  });

  it('VACUUM 压缩成功', async () => {
    const db = await createAriaDb();
    const result = await db.query('VACUUM') as { compactedLevels: number };
    expect(typeof result.compactedLevels).toBe('number');
    await db.close();
  });

  it('SAVEPOINT / ROLLBACK TO / RELEASE 真实执行', async () => {
    const db = await createAriaDb();
    await db.query('BEGIN');
    await db.query("UPDATE users SET age = 99 WHERE id = '1'");
    await db.query('SAVEPOINT sp_a');
    await db.query("UPDATE users SET age = 88 WHERE id = '1'");
    // 回滚到 savepoint：恢复 age=99
    await db.query('ROLLBACK TO SAVEPOINT sp_a');
    await db.query('RELEASE SAVEPOINT sp_a');
    await db.query('COMMIT');

    const rows = await db.query("SELECT age FROM users WHERE id = '1'") as Record<string, unknown>[];
    expect(rows[0].age).toBe(99);
    await db.close();
  });

  it('savepoint 已存在 → 抛 SAVEPOINT_EXISTS', async () => {
    const db = await createAriaDb();
    await db.query('BEGIN');
    await db.query('SAVEPOINT sp1');
    await expect(db.query('SAVEPOINT sp1')).rejects.toMatchObject({ code: 'SAVEPOINT_EXISTS' });
    await db.query('ROLLBACK');
    await db.close();
  });

  it('回滚到不存在的 savepoint → 抛 SAVEPOINT_NOT_FOUND', async () => {
    const db = await createAriaDb();
    await db.query('BEGIN');
    await expect(db.query('ROLLBACK TO nope')).rejects.toMatchObject({ code: 'SAVEPOINT_NOT_FOUND' });
    await db.query('ROLLBACK');
    await db.close();
  });
});

describe('v0.5.1 — 维护语句执行（Memory 引擎不支持）', () => {
  it('ANALYZE / REINDEX / VACUUM / SAVEPOINT → NOT_SUPPORTED', async () => {
    const db = new MetonaSqlark({ name: uniqueDB(), mode: 'memory' });
    await db.init();
    await db.defineTable('t', { id: { type: 'string', primaryKey: true } });

    await expect(db.query('ANALYZE TABLE t')).rejects.toMatchObject({ code: 'NOT_SUPPORTED' });
    await expect(db.query('REINDEX TABLE t')).rejects.toMatchObject({ code: 'NOT_SUPPORTED' });
    await expect(db.query('VACUUM')).rejects.toMatchObject({ code: 'NOT_SUPPORTED' });
    await expect(db.query('SAVEPOINT sp')).rejects.toMatchObject({ code: 'NOT_SUPPORTED' });
    await db.close();
  });

  it('EXPLAIN 在所有引擎可用（返回基本信息）', async () => {
    const db = new MetonaSqlark({ name: uniqueDB(), mode: 'memory' });
    await db.init();
    await db.defineTable('t', { id: { type: 'string', primaryKey: true } });
    await db.table('t').insert({ id: '1' });
    const plan = await db.query('EXPLAIN SELECT * FROM t') as Record<string, unknown>;
    expect(plan.type).toBe('SELECT');
    expect(plan.table).toBe('t');
    await db.close();
  });
});