flyer-crawler.projectium.com/src/services/emailService.server.test.ts

// src/services/emailService.server.test.ts
import { describe, it, expect, vi, beforeEach } from 'vitest';

// Use vi.hoisted to define mocks that need to be available inside vi.mock factories.
// This prevents "Cannot access before initialization" errors.
const mocks = vi.hoisted(() => ({
  sendMail: vi.fn().mockImplementation((mailOptions) => {
    console.log('[TEST DEBUG] mockSendMail called with:', mailOptions?.to);
    return Promise.resolve({
      messageId: 'default-id',
      message: Buffer.from('mock-email-content'),
    });
  }),
}));

vi.mock('nodemailer', () => {
  return {
    // Mock the default export which is what the service uses
    default: {
      // The createTransport function returns an object with a sendMail method
      createTransport: vi.fn(() => ({ sendMail: mocks.sendMail })),
    },
  };
});

// Mock the logger to prevent console output during tests
vi.mock('./logger.server', () => ({
  logger: {
    info: vi.fn(),
    debug: vi.fn(),
    error: vi.fn(),
    child: vi.fn().mockReturnThis(),
  },
}));

// Now that mocks are set up, we can import the service under test.
import {
  sendPasswordResetEmail,
  sendWelcomeEmail,
  sendDealNotificationEmail,
  processEmailJob,
} from './emailService.server';
import type { WatchedItemDeal } from '../types';
import { createMockWatchedItemDeal } from '../tests/utils/mockFactories';
import { logger } from './logger.server';
import type { Job } from 'bullmq';
import type { EmailJobData } from '../types/job-data';

describe('Email Service (Server)', () => {
  beforeEach(async () => {
    console.log('[TEST SETUP] Setting up Email Service mocks');
    vi.clearAllMocks();
    vi.stubEnv('FRONTEND_URL', 'https://test.flyer.com');
    // Reset to default successful implementation
    mocks.sendMail.mockImplementation((mailOptions: { to: string }) => {
      console.log('[TEST DEBUG] mockSendMail (default) called with:', mailOptions?.to);
      return Promise.resolve({
        messageId: 'default-mock-id',
        message: Buffer.from('mock-email-content'),
      });
    });
  });

  afterEach(() => {
    vi.unstubAllEnvs();
  });

  describe('sendPasswordResetEmail', () => {
    it('should call sendMail with the correct recipient, subject, and constructed link', async () => {
      const to = 'test@example.com';
      const token = 'mock-token-123';
      const expectedResetUrl = `https://test.flyer.com/reset-password?token=${token}`;

      await sendPasswordResetEmail(to, token, logger);

      expect(mocks.sendMail).toHaveBeenCalledTimes(1);
      const mailOptions = mocks.sendMail.mock.calls[0][0] as {
        to: string;
        subject: string;
        text: string;
        html: string;
      };

      expect(mailOptions.to).toBe(to);
      expect(mailOptions.subject).toBe('Your Password Reset Request');
      expect(mailOptions.text).toContain(expectedResetUrl);
      expect(mailOptions.html).toContain(`href="${expectedResetUrl}"`);
    });
  });

  describe('sendWelcomeEmail', () => {
    it('should send a personalized welcome email when a name is provided', async () => {
      const to = 'new.user@example.com';
      const name = 'Jane Doe';

      mocks.sendMail.mockResolvedValue({ messageId: 'test-id', message: Buffer.from('content') });

      await sendWelcomeEmail(to, name, logger);

      expect(mocks.sendMail).toHaveBeenCalledTimes(1);
      const mailOptions = mocks.sendMail.mock.calls[0][0] as {
        to: string;
        subject: string;
        text: string;
        html: string;
      };

      expect(mailOptions.to).toBe(to);
      expect(mailOptions.subject).toBe('Welcome to Flyer Crawler!');
      expect(mailOptions.text).toContain('Hello Jane Doe,');
      // Check for the key content instead of the exact HTML structure
      expect(mailOptions.html).toContain('Hello Jane Doe,');
    });

    it('should send a generic welcome email when a name is not provided', async () => {
      const to = 'another.user@example.com';

      mocks.sendMail.mockResolvedValue({ messageId: 'test-id', message: Buffer.from('content') });

      await sendWelcomeEmail(to, null, logger);

      expect(mocks.sendMail).toHaveBeenCalledTimes(1);
      const mailOptions = mocks.sendMail.mock.calls[0][0] as {
        to: string;
        subject: string;
        text: string;
        html: string;
      };

      expect(mailOptions.text).toContain('Hello there,');
      // Check for the key content instead of the exact HTML structure
      expect(mailOptions.html).toContain('Hello there,');
    });
  });

  describe('sendDealNotificationEmail', () => {
    const mockDeals = [
      createMockWatchedItemDeal({
        item_name: 'Apples',
        best_price_in_cents: 199,
        store: {
          store_id: 1,
          name: 'Green Grocer',
          logo_url: null,
          locations: [],
        },
      }),
      createMockWatchedItemDeal({
        item_name: 'Milk',
        best_price_in_cents: 350,
        store: {
          store_id: 2,
          name: 'Dairy Farm',
          logo_url: null,
          locations: [],
        },
      }),
    ];

    it('should send a personalized email with a list of deals', async () => {
      const to = 'deal.hunter@example.com';
      const name = 'Deal Hunter';

      await sendDealNotificationEmail(
        to,
        name,
        mockDeals as Partial<WatchedItemDeal>[] as WatchedItemDeal[],
        logger,
      );

      expect(mocks.sendMail).toHaveBeenCalledTimes(1);
      const mailOptions = mocks.sendMail.mock.calls[0][0] as {
        to: string;
        subject: string;
        text: string;
        html: string;
      };

      expect(mailOptions.to).toBe(to);
      expect(mailOptions.subject).toBe('New Deals Found on Your Watched Items!');
      // FIX: Use `stringContaining` to check for key parts of the HTML without being brittle about whitespace.
      // The actual HTML is a multi-line template string with tags like <h1>, <ul>, and <li>.
      expect(mailOptions.html).toEqual(expect.stringContaining('<h1>Hi Deal Hunter,</h1>'));
      expect(mailOptions.html).toEqual(
        expect.stringContaining(
          '<li>\n          <strong>Apples</strong> is on sale for \n          <strong>$1.99</strong> \n          at Green Grocer!\n        </li>',
        ),
      );
      expect(mailOptions.html).toEqual(
        expect.stringContaining(
          '<li>\n          <strong>Milk</strong> is on sale for \n          <strong>$3.50</strong> \n          at Dairy Farm!\n        </li>',
        ),
      );
      expect(mailOptions.html).toEqual(
        expect.stringContaining('<p>Check them out on the deals page!</p>'),
      );
    });

    it('should send a generic email when name is null', async () => {
      const to = 'anonymous.user@example.com';

      await sendDealNotificationEmail(
        to,
        null,
        mockDeals as Partial<WatchedItemDeal>[] as WatchedItemDeal[],
        logger,
      );

      expect(mocks.sendMail).toHaveBeenCalledTimes(1);
      const mailOptions = mocks.sendMail.mock.calls[0][0] as {
        to: string;
        subject: string;
        html: string;
      };

      expect(mailOptions.to).toBe(to);
      expect(mailOptions.html).toContain('Hi there,');
    });

    it('should log an error if sendMail fails', async () => {
      const to = 'fail@example.com';
      const name = 'Failure';
      const emailError = new Error('SMTP Connection Failed');
      mocks.sendMail.mockRejectedValue(emailError);

      await expect(
        sendDealNotificationEmail(
          to,
          name,
          mockDeals as Partial<WatchedItemDeal>[] as WatchedItemDeal[],
          logger,
        ),
      ).rejects.toThrow(emailError);

      expect(logger.error).toHaveBeenCalledWith(
        { err: emailError, to, subject: 'New Deals Found on Your Watched Items!' },
        'Failed to send email.',
      );
    });
  });

  describe('processEmailJob', () => {
    const mockJobData: EmailJobData = {
      to: 'job@example.com',
      subject: 'Job Email',
      html: '<p>Job</p>',
      text: 'Job',
    };

    const createMockJob = (data: EmailJobData): Job<EmailJobData> =>
      ({
        id: 'job-123',
        name: 'email-job',
        data,
        attemptsMade: 1,
      }) as unknown as Job<EmailJobData>;

    it('should call sendMail with job data and log success', async () => {
      const job = createMockJob(mockJobData);
      mocks.sendMail.mockResolvedValue({ messageId: 'job-test-id' });

      await processEmailJob(job);

      expect(mocks.sendMail).toHaveBeenCalledTimes(1);
      const mailOptions = mocks.sendMail.mock.calls[0][0];
      expect(mailOptions.to).toBe(mockJobData.to);
      expect(mailOptions.subject).toBe(mockJobData.subject);
      expect(logger.info).toHaveBeenCalledWith('Picked up email job.');
      expect(logger.info).toHaveBeenCalledWith(
        { to: 'job@example.com', subject: 'Job Email', messageId: 'job-test-id' },
        'Email sent successfully.',
      );
    });

    it('should log an error and re-throw if sendMail fails', async () => {
      const job = createMockJob(mockJobData);
      const emailError = new Error('SMTP Connection Failed');
      mocks.sendMail.mockRejectedValue(emailError);

      await expect(processEmailJob(job)).rejects.toThrow(emailError);

      expect(logger.error).toHaveBeenCalledWith(
        { err: emailError, jobData: mockJobData, attemptsMade: 1 },
        'Email job failed.',
      );
    });

    it('should handle non-Error objects thrown during processing', async () => {
      const job = createMockJob(mockJobData);
      const emailErrorString = 'SMTP Connection Failed as a string';
      mocks.sendMail.mockRejectedValue(emailErrorString);

      await expect(processEmailJob(job)).rejects.toThrow(emailErrorString);

      expect(logger.error).toHaveBeenCalledWith(
        {
          err: expect.objectContaining({ message: emailErrorString }),
          jobData: mockJobData,
          attemptsMade: 1,
        },
        'Email job failed.',
      );
    });
  });
});