import { beforeEach, describe, expect, it, vi } from 'vitest';

const appendFileMock = vi.hoisted(() => vi.fn());
vi.mock('fs/promises', () => ({ appendFile: appendFileMock }));

const { appendDashboardWarning, clearDashboardWarningDedupe } = await import('./dashboard-alerts.js');

describe('dashboard-alerts', () => {
  beforeEach(() => {
    vi.clearAllMocks();
    clearDashboardWarningDedupe();
    delete process.env.HERMES_DASHBOARD_ALERT_LOG;
  });

  it('does nothing when the alert log is not configured', async () => {
    const wrote = await appendDashboardWarning({ severity: 'warn', instance: 'vijay', message: 'gateway down' });
    expect(wrote).toBe(false);
    expect(appendFileMock).not.toHaveBeenCalled();
  });

  it('writes a routed warning line when configured', async () => {
    process.env.HERMES_DASHBOARD_ALERT_LOG = '/tmp/hermes-dashboard-warnings.log';
    const wrote = await appendDashboardWarning(
      { severity: 'critical', instance: 'bheem', message: 'backup missing' },
      Date.parse('2026-05-31T07:00:00Z'),
    );

    expect(wrote).toBe(true);
    expect(appendFileMock).toHaveBeenCalledWith(
      '/tmp/hermes-dashboard-warnings.log',
      '2026-05-31T07:00:00.000Z CRITICAL instance=bheem backup missing\n',
      'utf8',
    );
  });

  it('deduplicates for one hour and writes again after expiry', async () => {
    process.env.HERMES_DASHBOARD_ALERT_LOG = '/tmp/hermes-dashboard-warnings.log';
    const input = { severity: 'warn' as const, instance: 'all' as const, message: 'shared warning' };
    expect(await appendDashboardWarning(input, 1_000)).toBe(true);
    expect(await appendDashboardWarning(input, 2_000)).toBe(false);
    expect(await appendDashboardWarning(input, 3_602_000)).toBe(true);
    expect(appendFileMock).toHaveBeenCalledTimes(2);
  });
});