const { test } = require('node:test');
const assert = require('node:assert/strict');
const fs = require('node:fs');
const vm = require('node:vm');

// Execute the actual server shutdown registration/handler, without booting DB or routes.
for (const failure of [null, 'audit', 'db', 'mcp']) {
  test('server drains HTTP, audit and DB before MCP/exit: ' + (failure || 'success'), async () => {
    const source = fs.readFileSync(require.resolve('../server'), 'utf8');
    const events = [];
    const signals = {};
    let httpClosed;
    let deadline;
    let deadlineMs;
    let releaseAudit;
    const auditGate = new Promise(resolve => { releaseAudit = resolve; });
    let releaseDb;
    const dbGate = new Promise(resolve => { releaseDb = resolve; });
    const context = {
      console: { log() {}, error() {} },
      imageWorker: { async stop() { events.push('images.stop'); } },
      server: { close(callback) { events.push('http.close'); httpClosed = callback; } },
      process: { on(signal, callback) { signals[signal] = callback; }, exit(code) { events.push('exit:' + code); } },
      setTimeout(callback, ms) { deadline = callback; deadlineMs = ms; return { unref() { events.push('guard.unref'); } }; },
      clearInterval(id) { assert.equal(id, 123); events.push('cleanup.clear'); },
      require(name) {
        if (name.endsWith('/auditQueue')) return { async drainAll() {
          events.push('audit.start'); await auditGate; events.push('audit.end');
          if (failure === 'audit') throw new Error('failure');
        } };
        if (name.endsWith('/database')) return { _cleanupInterval: 123, pool: { async end() {
          events.push('db.start'); await dbGate; events.push('db.end');
          if (failure === 'db') throw new Error('failure');
        } } };
        if (name.endsWith('/clinicalMcpClient')) return { async closeMcpSession() {
          events.push('mcp.close'); if (failure === 'mcp') throw new Error('secret');
        } };
        throw new Error('unexpected dependency');
      }
    };
    vm.runInNewContext(source.slice(source.indexOf('var shuttingDown = false;')), context);
    signals.SIGTERM();
    signals.SIGINT();
    assert.deepEqual(events, ['images.stop', 'http.close', 'guard.unref']);
    assert.equal(deadlineMs, 9000);
    const done = httpClosed();
    assert.deepEqual(events.slice(3), ['audit.start']);
    releaseAudit();
    await new Promise(resolve => setImmediate(resolve));
    assert.deepEqual(events.slice(3), ['audit.start', 'audit.end', 'cleanup.clear', 'db.start']);
    releaseDb();
    await done;
    assert.deepEqual(events.slice(3), ['audit.start', 'audit.end', 'cleanup.clear', 'db.start', 'db.end', 'mcp.close', 'exit:0']);
    deadline();
    assert.equal(events.at(-1), 'exit:1');
  });
}