import { describe, expect, it } from 'vitest';
import { fallbackDashboardSnapshot } from '../../src/data/mockDashboard';
import { buildSnapshotPatch } from './liveSync';

describe('buildSnapshotPatch', () => {
  it('returns only changed top-level dashboard sections', () => {
    const nextSnapshot = {
      ...fallbackDashboardSnapshot,
      traffic: {
        ...fallbackDashboardSnapshot.traffic,
        totalBytes: fallbackDashboardSnapshot.traffic.totalBytes + 512,
      },
    };

    expect(buildSnapshotPatch(fallbackDashboardSnapshot, nextSnapshot)).toEqual({
      traffic: nextSnapshot.traffic,
    });
  });

  it('returns a full patch when no previous snapshot exists', () => {
    expect(buildSnapshotPatch(null, fallbackDashboardSnapshot)).toEqual({
      service: fallbackDashboardSnapshot.service,
      traffic: fallbackDashboardSnapshot.traffic,
      users: fallbackDashboardSnapshot.users,
      attention: fallbackDashboardSnapshot.attention,
      userRecords: fallbackDashboardSnapshot.userRecords,
      system: fallbackDashboardSnapshot.system,
    });
  });
});