import { fileStorageService } from '../../services/fileStorageService';
import { uploadMonitoringService } from '../../services/uploadMonitoringService';
import { unifiedDocumentProcessor } from '../../services/unifiedDocumentProcessor';

// Mock dependencies
jest.mock('../../services/fileStorageService');
jest.mock('../../services/uploadMonitoringService');
jest.mock('../../services/unifiedDocumentProcessor');

describe('Error Handling and Recovery Tests', () => {
  beforeEach(() => {
    jest.clearAllMocks();
  });

  describe('GCS Error Scenarios', () => {
    it('should handle GCS bucket access errors', async () => {
      (fileStorageService.storeFile as jest.Mock).mockRejectedValue(
        new Error('Access denied to bucket')
      );

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(false);
      expect(result.error).toContain('Failed to store file');
    });

    it('should handle GCS network timeout errors', async () => {
      (fileStorageService.storeFile as jest.Mock).mockRejectedValue(
        new Error('Request timeout')
      );

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(false);
    });

    it('should handle GCS quota exceeded errors', async () => {
      (fileStorageService.storeFile as jest.Mock).mockRejectedValue(
        new Error('Quota exceeded')
      );

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(false);
    });
  });

  describe('Retry Logic', () => {
    it('should retry failed GCS operations', async () => {
      (fileStorageService.storeFile as jest.Mock)
        .mockRejectedValueOnce(new Error('Network error'))
        .mockRejectedValueOnce(new Error('Temporary failure'))
        .mockResolvedValueOnce({
          success: true,
          fileInfo: {
            originalName: 'test.pdf',
            filename: 'test-file.pdf',
            path: 'uploads/test-user/test-file.pdf',
            size: 1024,
            mimetype: 'application/pdf',
            uploadedAt: new Date(),
            gcsPath: 'uploads/test-user/test-file.pdf',
          },
        });

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(true);
      expect(fileStorageService.storeFile).toHaveBeenCalledTimes(3);
    });

    it('should fail after maximum retries', async () => {
      (fileStorageService.storeFile as jest.Mock).mockRejectedValue(
        new Error('Persistent failure')
      );

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(false);
    });
  });

  describe('Error Monitoring and Logging', () => {
    it('should track upload failures in monitoring service', async () => {
      (fileStorageService.storeFile as jest.Mock).mockRejectedValue(
        new Error('Storage failed')
      );

      try {
        await fileStorageService.storeFile(
          { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
          'test-user'
        );
      } catch (error) {
        // Expected to fail
      }

      expect(uploadMonitoringService.trackUploadEvent).toHaveBeenCalledWith(
        expect.objectContaining({
          status: 'failed',
          error: expect.objectContaining({
            message: expect.stringContaining('Storage failed'),
            type: 'storage_error',
          }),
        })
      );
    });

    it('should categorize different types of errors', async () => {
      const errorScenarios = [
        { error: new Error('Network timeout'), expectedType: 'network_error' },
        { error: new Error('Access denied'), expectedType: 'permission_error' },
        { error: new Error('Quota exceeded'), expectedType: 'quota_error' },
        { error: new Error('Invalid file'), expectedType: 'validation_error' },
      ];

      for (const scenario of errorScenarios) {
        (fileStorageService.storeFile as jest.Mock).mockRejectedValue(scenario.error);

        try {
          await fileStorageService.storeFile(
            { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
            'test-user'
          );
        } catch (error) {
          // Expected to fail
        }
      }

      expect(uploadMonitoringService.trackUploadEvent).toHaveBeenCalledTimes(4);
    });
  });

  describe('Graceful Degradation', () => {
    it('should handle partial service failures', async () => {
      // Mock storage success but processing failure
      (fileStorageService.storeFile as jest.Mock).mockResolvedValue({
        success: true,
        fileInfo: {
          originalName: 'test.pdf',
          filename: 'test-file.pdf',
          path: 'uploads/test-user/test-file.pdf',
          size: 1024,
          mimetype: 'application/pdf',
          uploadedAt: new Date(),
          gcsPath: 'uploads/test-user/test-file.pdf',
        },
      });

      (unifiedDocumentProcessor.processDocument as jest.Mock).mockRejectedValue(
        new Error('Processing service unavailable')
      );

      const storageResult = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(storageResult.success).toBe(true);
      // File should still be stored even if processing fails
    });

    it('should provide meaningful error messages to users', async () => {
      (fileStorageService.storeFile as jest.Mock).mockRejectedValue(
        new Error('GCS bucket not found')
      );

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(false);
      expect(result.error).toContain('Failed to store file');
    });
  });

  describe('Recovery Mechanisms', () => {
    it('should handle service recovery after failures', async () => {
      // Simulate service recovery
      (fileStorageService.storeFile as jest.Mock)
        .mockRejectedValueOnce(new Error('Service unavailable'))
        .mockResolvedValueOnce({
          success: true,
          fileInfo: {
            originalName: 'test.pdf',
            filename: 'test-file.pdf',
            path: 'uploads/test-user/test-file.pdf',
            size: 1024,
            mimetype: 'application/pdf',
            uploadedAt: new Date(),
            gcsPath: 'uploads/test-user/test-file.pdf',
          },
        });

      const result = await fileStorageService.storeFile(
        { originalname: 'test.pdf', size: 1024, mimetype: 'application/pdf' },
        'test-user'
      );

      expect(result.success).toBe(true);
    });

    it('should handle connection restoration', async () => {
      (fileStorageService.testConnection as jest.Mock)
        .mockResolvedValueOnce(false) // Connection lost
        .mockResolvedValueOnce(true); // Connection restored

      const connection1 = await fileStorageService.testConnection();
      const connection2 = await fileStorageService.testConnection();

      expect(connection1).toBe(false);
      expect(connection2).toBe(true);
    });
  });
}); 