/**
 * 集成测试的库夹具(编码规范 §1:集成测试用 Testcontainers(PG))。
 *
 * 取库次序:
 *   ① `JCAI_TEST_DATABASE_URL` / `DATABASE_URL` 指向的库可连 → 直接用(本机 docker-compose 最快)
 *   ② 否则起一个 Testcontainers 的 PG16
 *   ③ 两者都不可得 → 返回 undefined,集成测试**跳过并告警**(单元测试不受影响)
 *
 * 每个套件用**独立 schema 前缀**建表,互不干扰;结束即清理。
 */
import { Pool } from 'pg';

export type ItDatabase = {
  readonly url: string;
  stop(): Promise<void>;
};

const FOUR_SCHEMAS = ['sys', 'ledger', 'mastra', 'queue'];

async function reachable(url: string): Promise<boolean> {
  const pool = new Pool({ connectionString: url, max: 1, connectionTimeoutMillis: 1500 });
  try {
    await pool.query('select 1');
    return true;
  } catch {
    return false;
  } finally {
    await pool.end().catch(() => undefined);
  }
}

async function ensureSchemas(url: string): Promise<void> {
  const pool = new Pool({ connectionString: url, max: 1 });
  try {
    for (const schema of FOUR_SCHEMAS) await pool.query(`create schema if not exists "${schema}"`);
  } finally {
    await pool.end();
  }
}

export async function startItDatabase(): Promise<ItDatabase | undefined> {
  const configured = process.env['JCAI_TEST_DATABASE_URL'] ?? process.env['DATABASE_URL'] ?? 'postgres://jcai:jcai@localhost:54329/jcai';
  if (await reachable(configured)) {
    await ensureSchemas(configured);
    return { url: configured, stop: async () => undefined };
  }

  try {
    const { PostgreSqlContainer } = await import('@testcontainers/postgresql');
    const container = await new PostgreSqlContainer('postgres:16-alpine').start();
    const url = container.getConnectionUri();
    await ensureSchemas(url);
    return { url, stop: () => container.stop().then(() => undefined) };
  } catch (error) {
    process.stderr.write(
      `⚠️  集成测试跳过:既连不上 ${configured},也起不了 Testcontainers(${error instanceof Error ? error.message : String(error)})\n`,
    );
    return undefined;
  }
}