import test from 'node:test';
import assert from 'node:assert/strict';
import { Agent, acquireQvac, releaseQvac, closeQvac, qvacStatus } from '../daemon/qvac-master.js';

test('concurrent master acquisition loads once and failed acquisition does not leak owners', async () => {
  const original = { resources: Agent.engine.resources, load: Agent.engine.load, close: Agent.engine.close };
  let loads = 0;
  Agent.engine.resources = async () => ({ gpus: [{}] });
  Agent.engine.load = async () => { loads++; return { device: 'gpu' }; };
  Agent.engine.close = async () => {};
  try {
    await Promise.all([acquireQvac(), acquireQvac()]);
    assert.equal(loads, 1); assert.equal(qvacStatus().owners, 2);
    releaseQvac(); releaseQvac(); await closeQvac();
    Agent.engine.resources = async () => { throw new Error('discovery failed'); };
    await assert.rejects(acquireQvac(), /discovery failed/);
    assert.equal(qvacStatus().owners, 0);
    Agent.engine.resources = async () => ({ gpus: [{}] });
    await acquireQvac(); assert.equal(loads, 2); releaseQvac();
  } finally { await closeQvac(); Object.assign(Agent.engine, original); }
});