import { BadRequestException, Logger } from '@nestjs/common';
import { ApplicationErrorLoggerService } from './application-error-logger.service';
import { sanitizeContext, maskEmail } from './application-error-sanitizer';
import { ApplicationErrorCategory, ApplicationErrorCode } from './application-error-codes';

describe('ApplicationErrorLoggerService', () => {
  const config = { get: jest.fn((key: string) => (key === 'NODE_ENV' ? 'test' : undefined)) };

  function createService(save = jest.fn().mockResolvedValue(undefined)) {
    const repo = {
      create: jest.fn((value) => value),
      save,
    };
    return { service: new ApplicationErrorLoggerService(repo as any, config as any), repo };
  }

  it('stores normal Error objects with stack and type', async () => {
    const { service, repo } = createService();
    const error = new Error('SMTP failed');
    await service.log({ error, code: 'TEST_ERROR', category: ApplicationErrorCategory.EMAIL, handled: true });
    expect(repo.save).toHaveBeenCalledWith(expect.objectContaining({ message: 'SMTP failed', errorType: 'Error', code: 'TEST_ERROR', handled: true }));
    expect(repo.save.mock.calls[0][0].stackTrace).toContain('Error: SMTP failed');
  });

  it('handles NestJS HTTP exceptions', async () => {
    const { service, repo } = createService();
    await service.log({ error: new BadRequestException({ code: 'BAD_INPUT', message: 'Invalid data' }) });
    expect(repo.save).toHaveBeenCalledWith(expect.objectContaining({ httpStatusCode: 400, code: 'BAD_INPUT', level: 'warning' }));
  });

  it('handles unknown error values safely', async () => {
    const { service, repo } = createService();
    await service.log({ error: { reason: 'broken' } });
    expect(repo.save).toHaveBeenCalledWith(expect.objectContaining({ message: '{"reason":"broken"}', errorType: 'object' }));
  });

  it('sanitizes nested sensitive fields and masks email addresses', () => {
    const circular: Record<string, unknown> = { email: 'max.mustermann@example.com', nested: { token: 'secret', password: 'x' } };
    circular.self = circular;
    expect(sanitizeContext(circular)).toEqual({
      email: 'm***@example.com',
      nested: {},
      self: '[Circular]',
    });
    expect(maskEmail('maria@example.com')).toBe('m***@example.com');
  });

  it('stores request, user and tenant context', async () => {
    const { service, repo } = createService();
    await service.log({
      error: new Error('failed'),
      requestContext: {
        correlationId: 'corr-1',
        userId: 'user-1',
        tenantId: 'tenant-1',
        method: 'POST',
        path: '/api/test',
      },
    });
    expect(repo.save).toHaveBeenCalledWith(expect.objectContaining({ correlationId: 'corr-1', userId: 'user-1', tenantId: 'tenant-1' }));
  });

  it('swallows database write errors', async () => {
    jest.spyOn(Logger.prototype, 'error').mockImplementation(() => undefined);
    const { service } = createService(jest.fn().mockRejectedValue(new Error('db down')));
    await expect(service.log({ error: new Error('original') })).resolves.toBeUndefined();
  });

  it('does not persist the same error twice', async () => {
    const { service, repo } = createService();
    const error = new Error('only once');
    await service.log({ error });
    await service.log({ error });
    expect(repo.save).toHaveBeenCalledTimes(1);
  });

  it('can record background job failures', async () => {
    const { service, repo } = createService();
    await service.log({
      error: new Error('job failed'),
      category: ApplicationErrorCategory.BACKGROUND_JOB,
      code: ApplicationErrorCode.BACKGROUND_JOB_FAILED,
      operation: 'dailyImport',
      handled: true,
    });
    expect(repo.save).toHaveBeenCalledWith(expect.objectContaining({ category: 'BACKGROUND_JOB', code: 'BACKGROUND_JOB_FAILED', operation: 'dailyImport' }));
  });
});