// Copyright (c) 2026 Gordon Bolton. MIT License.
const { 
  DownloadClientRegistry, 
  registry,
  initializeClients,
  getAllClients,
  getClient,
  getClientsByType,
  getAllDownloads,
  getDownloadsByClientType,
  testAllConnections,
  getAllClientStatuses
} = require('../../server/utils/downloadClients');

// Mock config and clients
jest.mock('../../server/utils/config', () => ({
  getSABnzbdInstances: jest.fn(),
  getQbittorrentInstances: jest.fn(),
  getTransmissionInstances: jest.fn()
}));

jest.mock('../../server/utils/logger', () => ({
  logToFile: jest.fn()
}));

jest.mock('../../server/clients/SABnzbdClient', () => {
  return jest.fn().mockImplementation((config) => ({
    getClientType: () => 'sabnzbd',
    getInstanceId: () => config.id,
    name: config.name,
    getActiveDownloads: jest.fn().mockResolvedValue([
      { id: 'sab1', title: 'SAB Download 1', client: 'sabnzbd' }
    ]),
    testConnection: jest.fn().mockResolvedValue(true),
    getClientStatus: jest.fn().mockResolvedValue({ status: 'active' })
  }));
});

jest.mock('../../server/clients/QBittorrentClient', () => {
  return jest.fn().mockImplementation((config) => ({
    getClientType: () => 'qbittorrent',
    getInstanceId: () => config.id,
    name: config.name,
    getActiveDownloads: jest.fn().mockResolvedValue([
      { id: 'qb1', title: 'QB Download 1', client: 'qbittorrent' }
    ]),
    testConnection: jest.fn().mockResolvedValue(true),
    getClientStatus: jest.fn().mockResolvedValue({ status: 'active' }),
    resetFallbackFlag: jest.fn()
  }));
});

jest.mock('../../server/clients/TransmissionClient', () => {
  return jest.fn().mockImplementation((config) => ({
    getClientType: () => 'transmission',
    getInstanceId: () => config.id,
    name: config.name,
    getActiveDownloads: jest.fn().mockResolvedValue([
      { id: 'trans1', title: 'Trans Download 1', client: 'transmission' }
    ]),
    testConnection: jest.fn().mockResolvedValue(true),
    getClientStatus: jest.fn().mockResolvedValue({ status: 'active' })
  }));
});

describe('DownloadClientRegistry', () => {
  let testRegistry;
  const mockConfig = require('../../server/utils/config');

  beforeEach(() => {
    testRegistry = new DownloadClientRegistry();
    jest.clearAllMocks();
  });

  describe('Initialization', () => {
    it('should initialize clients from config', async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([
        { id: 'sab1', name: 'SAB 1', url: 'http://sab1', apiKey: 'key1' }
      ]);
      
      mockConfig.getQbittorrentInstances.mockReturnValue([
        { id: 'qb1', name: 'QB 1', url: 'http://qb1', username: 'user', password: 'pass' }
      ]);
      
      mockConfig.getTransmissionInstances.mockReturnValue([
        { id: 'trans1', name: 'Trans 1', url: 'http://trans1', username: 'user', password: 'pass' }
      ]);

      await testRegistry.initialize();

      expect(testRegistry.getAllClients()).toHaveLength(3);
      expect(testRegistry.getClient('sab1')).toBeTruthy();
      expect(testRegistry.getClient('qb1')).toBeTruthy();
      expect(testRegistry.getClient('trans1')).toBeTruthy();
    });

    it('should handle empty config', async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([]);
      mockConfig.getQbittorrentInstances.mockReturnValue([]);
      mockConfig.getTransmissionInstances.mockReturnValue([]);

      await testRegistry.initialize();

      expect(testRegistry.getAllClients()).toHaveLength(0);
    });

    it('should not initialize twice', async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([]);
      mockConfig.getQbittorrentInstances.mockReturnValue([]);
      mockConfig.getTransmissionInstances.mockReturnValue([]);

      await testRegistry.initialize();
      await testRegistry.initialize(); // Should not call config again

      expect(mockConfig.getSABnzbdInstances).toHaveBeenCalledTimes(1);
    });

    it('should handle client creation errors gracefully', async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([
        { id: 'invalid-sab', name: 'Invalid SAB' } // Missing required fields
      ]);

      await testRegistry.initialize();

      expect(testRegistry.getAllClients()).toHaveLength(0);
    });
  });

  describe('Client Management', () => {
    beforeEach(async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([
        { id: 'sab1', name: 'SAB 1', url: 'http://sab1', apiKey: 'key1' }
      ]);
      mockConfig.getQbittorrentInstances.mockReturnValue([]);
      mockConfig.getTransmissionInstances.mockReturnValue([]);
      
      await testRegistry.initialize();
    });

    it('should get all clients', () => {
      const clients = testRegistry.getAllClients();
      expect(clients).toHaveLength(1);
      expect(clients[0].getClientType()).toBe('sabnzbd');
    });

    it('should get client by ID', () => {
      const client = testRegistry.getClient('sab1');
      expect(client).toBeTruthy();
      expect(client.getInstanceId()).toBe('sab1');
    });

    it('should return null for non-existent client', () => {
      const client = testRegistry.getClient('nonexistent');
      expect(client).toBeNull();
    });

    it('should get clients by type', () => {
      const sabClients = testRegistry.getClientsByType('sabnzbd');
      expect(sabClients).toHaveLength(1);
      
      const qbClients = testRegistry.getClientsByType('qbittorrent');
      expect(qbClients).toHaveLength(0);
    });
  });

  describe('Download Management', () => {
    beforeEach(async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([
        { id: 'sab1', name: 'SAB 1', url: 'http://sab1', apiKey: 'key1' }
      ]);
      mockConfig.getQbittorrentInstances.mockReturnValue([
        { id: 'qb1', name: 'QB 1', url: 'http://qb1', username: 'user', password: 'pass' }
      ]);
      mockConfig.getTransmissionInstances.mockReturnValue([]);
      
      await testRegistry.initialize();
    });

    it('should get all downloads from all clients', async () => {
      const downloads = await testRegistry.getAllDownloads();
      
      expect(downloads).toHaveLength(2);
      expect(downloads[0].client).toBe('sabnzbd');
      expect(downloads[1].client).toBe('qbittorrent');
    });

    it('should reset fallback flags for qBittorrent clients', async () => {
      const qbClient = testRegistry.getClient('qb1');
      
      await testRegistry.getAllDownloads();
      
      expect(qbClient.resetFallbackFlag).toHaveBeenCalled();
    });

    it('should get downloads grouped by client type', async () => {
      const downloadsByType = await testRegistry.getDownloadsByClientType();
      
      expect(downloadsByType.sabnzbd).toHaveLength(1);
      expect(downloadsByType.qbittorrent).toHaveLength(1);
      expect(downloadsByType.transmission).toBeUndefined();
    });

    it('should handle client errors gracefully', async () => {
      const sabClient = testRegistry.getClient('sab1');
      sabClient.getActiveDownloads.mockRejectedValue(new Error('Client error'));

      const downloads = await testRegistry.getAllDownloads();
      
      expect(downloads).toHaveLength(1); // Only qBittorrent succeeds
    });
  });

  describe('Connection Testing', () => {
    beforeEach(async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([
        { id: 'sab1', name: 'SAB 1', url: 'http://sab1', apiKey: 'key1' }
      ]);
      mockConfig.getQbittorrentInstances.mockReturnValue([
        { id: 'qb1', name: 'QB 1', url: 'http://qb1', username: 'user', password: 'pass' }
      ]);
      mockConfig.getTransmissionInstances.mockReturnValue([]);
      
      await testRegistry.initialize();
    });

    it('should test all connections', async () => {
      const results = await testRegistry.testAllConnections();
      
      expect(results).toHaveLength(2);
      expect(results[0]).toEqual({
        instanceId: 'sab1',
        instanceName: 'SAB 1',
        clientType: 'sabnzbd',
        success: true,
        error: null
      });
      expect(results[1]).toEqual({
        instanceId: 'qb1',
        instanceName: 'QB 1',
        clientType: 'qbittorrent',
        success: true,
        error: null
      });
    });

    it('should handle connection test failures', async () => {
      const sabClient = testRegistry.getClient('sab1');
      sabClient.testConnection.mockRejectedValue(new Error('Connection failed'));

      const results = await testRegistry.testAllConnections();
      
      expect(results[0].success).toBe(false);
      expect(results[0].error).toBe('Connection failed');
    });
  });

  describe('Client Status', () => {
    beforeEach(async () => {
      mockConfig.getSABnzbdInstances.mockReturnValue([
        { id: 'sab1', name: 'SAB 1', url: 'http://sab1', apiKey: 'key1' }
      ]);
      mockConfig.getQbittorrentInstances.mockReturnValue([]);
      mockConfig.getTransmissionInstances.mockReturnValue([]);
      
      await testRegistry.initialize();
    });

    it('should get all client statuses', async () => {
      const statuses = await testRegistry.getAllClientStatuses();
      
      expect(statuses).toHaveLength(1);
      expect(statuses[0]).toEqual({
        instanceId: 'sab1',
        instanceName: 'SAB 1',
        clientType: 'sabnzbd',
        status: { status: 'active' }
      });
    });

    it('should handle status request errors', async () => {
      const sabClient = testRegistry.getClient('sab1');
      sabClient.getClientStatus.mockRejectedValue(new Error('Status error'));

      const statuses = await testRegistry.getAllClientStatuses();
      
      expect(statuses[0].status).toBeNull();
      expect(statuses[0].error).toBe('Status error');
    });
  });
});

describe('Convenience Functions', () => {
  beforeEach(() => {
    jest.clearAllMocks();
  });

  it('should delegate to singleton registry', async () => {
    const mockConfig = require('../../server/utils/config');
    mockConfig.getSABnzbdInstances.mockReturnValue([]);
    mockConfig.getQbittorrentInstances.mockReturnValue([]);
    mockConfig.getTransmissionInstances.mockReturnValue([]);

    await initializeClients();
    
    expect(getAllClients()).toBeInstanceOf(Array);
    expect(getClient('test')).toBeNull();
    expect(getClientsByType('sabnzbd')).toBeInstanceOf(Array);
    expect(await getAllDownloads()).toBeInstanceOf(Array);
    expect(await getDownloadsByClientType()).toBeInstanceOf(Object);
    expect(await testAllConnections()).toBeInstanceOf(Array);
    expect(await getAllClientStatuses()).toBeInstanceOf(Array);
  });
});