const fs = require('fs');
const path = require('path');

jest.mock('child_process', () => ({
  exec: jest.fn(),
}));

jest.mock('../programs/log', () => ({
  logSnapshot: jest.fn(),
}));

const { exec } = require('child_process');
const { snapshot } = require('../programs/screenShot');

class DummyCamera {
  async snapshotHighRes() {
    return Promise.resolve();
  }
}

const tempDir = path.join(__dirname, 'data', 'temp');
const fixedNow = 1778819665744;

beforeEach(() => {
  jest.clearAllMocks();
  if (typeof Date.now.mockRestore === 'function') {
    Date.now.mockRestore();
  }
  jest.spyOn(Date, 'now').mockReturnValue(fixedNow);
  if (!fs.existsSync(tempDir)) {
    fs.mkdirSync(tempDir, { recursive: true });
  }

  
  // Quellpfade
  const sourceDir = path.join(__dirname, 'data', 'screenShots'); 

  const filesToCopy = [
    'snapshot_video0_1778819665744.jpg',
    'snapshot_video1_1778819665744.jpg',
  ];

  // Dateien kopieren
  for (const file of filesToCopy) {
    const src = path.join(sourceDir, file);
    const dest = path.join(tempDir, file);

    if (fs.existsSync(src)) {
      fs.copyFileSync(src, dest);
    } else {
      throw new Error(`Testdatei fehlt: ${src}`);
    }
  }

});

afterEach(() => {
  if (fs.existsSync(tempDir)) {
    fs.rmSync(tempDir, { recursive: true, force: true });
  }
  if (typeof Date.now.mockRestore === 'function') {
    Date.now.mockRestore();
  }
  
});

test('snapshot calls both camera snapshotHighRes methods and sends a snapshot response', async () => {
  const cam0 = new DummyCamera();
  const cam1 = new DummyCamera();
  cam0.snapshotHighRes = jest.fn(() => Promise.resolve());
  cam1.snapshotHighRes = jest.fn(() => Promise.resolve());
  const ws = { send: jest.fn() };

  const expectedName0 = `snapshot_video0_${fixedNow}.jpg`;
  const expectedName1 = `snapshot_video1_${fixedNow}.jpg`;
  const expectedAnnotated = path.join(tempDir, expectedName0.replace('.jpg', '_two_cam_annotated.jpg'));
  const expectedOverlay = path.join(tempDir, expectedName0.replace('.jpg', '_two_cam_overlay.png'));
  const expectedCsv = path.join(tempDir, expectedName0.replace('.jpg', '_two_cam.csv'));

  exec.mockImplementation((command, callback) => {
    fs.writeFileSync(expectedAnnotated, '');
    fs.writeFileSync(expectedOverlay, '');
    fs.writeFileSync(expectedCsv, '');
    callback(null, 'ok', '');
  });

  const sentPromise = new Promise((resolve) => {
    ws.send.mockImplementation((message) => resolve(message));
  });

  snapshot(tempDir, cam0, cam1, ws);

  const rawMessage = await sentPromise;
  const response = JSON.parse(rawMessage);

  expect(cam0.snapshotHighRes).toHaveBeenCalledWith(path.join(tempDir, expectedName0));
  expect(cam1.snapshotHighRes).toHaveBeenCalledWith(path.join(tempDir, expectedName1));
  expect(exec).toHaveBeenCalled();
  expect(response).toEqual({
    type: 'snapshot',
    ok: true,
    url: `/snapshots/${expectedName0}`,
    urlApp: `/snapshots/${expectedName0.replace('.jpg', '_two_cam_annotated.jpg')}`,
    overlay: `/snapshots/${expectedName0.replace('.jpg', '_two_cam_overlay.png')}`,
    overlayCSV: `/snapshots/${expectedName0.replace('.jpg', '_two_cam.csv')}`,
  });
});