import mongoose from 'mongoose';
import request from 'supertest';
import express from 'express';
import { MongoMemoryServer } from 'mongodb-memory-server';
import { jest, describe, it, expect, beforeAll, afterAll, beforeEach } from '@jest/globals';
import Event from '../src/models/Event';
import eventRoutes from '../src/routes/events';

// Mock auth middleware
jest.mock('../src/middleware/auth', () => ({
  checkAuth: (req: any, res: any, next: any) => next(),
}));

describe('Events API', () => {
  let app: express.Application;
  let mongoServer: MongoMemoryServer;

  beforeAll(async () => {
    // Set up MongoDB Memory Server
    mongoServer = await MongoMemoryServer.create();
    const uri = mongoServer.getUri();
    await mongoose.connect(uri);

    // Set up Express app
    app = express();
    app.use(express.json());
    app.use('/api/events', eventRoutes);
  });

  afterAll(async () => {
    await mongoose.disconnect();
    await mongoServer.stop();
  });

  beforeEach(async () => {
    // Clear the database before each test
    await Event.deleteMany({});
  });

  // Sample event data
  const sampleEvent = {
    title: 'Test Event',
    description: 'This is a test event',
    date: new Date('2025-05-15'),
    time: '18:00 - 20:00',
    location: 'Test Location',
    category: 'social',
    status: 'published',
    registrationRequired: true,
    maxAttendees: 50,
  };

  describe('GET /api/events', () => {
    it('should return an empty array when no events exist', async () => {
      const response = await request(app).get('/api/events');
      expect(response.status).toBe(200);
      expect(response.body.events).toEqual([]);
      expect(response.body.pagination.total).toBe(0);
    });

    it('should return events when they exist', async () => {
      // Create a test event
      await Event.create(sampleEvent);

      const response = await request(app).get('/api/events');
      expect(response.status).toBe(200);
      expect(response.body.events.length).toBe(1);
      expect(response.body.events[0].title).toBe('Test Event');
      expect(response.body.pagination.total).toBe(1);
    });

    it('should filter events by status', async () => {
      // Create published event
      await Event.create(sampleEvent);
      
      // Create draft event
      await Event.create({
        ...sampleEvent,
        title: 'Draft Event',
        status: 'draft',
      });

      // Test filtering by published status
      const publishedResponse = await request(app).get('/api/events?status=published');
      expect(publishedResponse.status).toBe(200);
      expect(publishedResponse.body.events.length).toBe(1);
      expect(publishedResponse.body.events[0].title).toBe('Test Event');
      
      // Test filtering by draft status
      const draftResponse = await request(app).get('/api/events?status=draft');
      expect(draftResponse.status).toBe(200);
      expect(draftResponse.body.events.length).toBe(1);
      expect(draftResponse.body.events[0].title).toBe('Draft Event');
    });
  });

  describe('GET /api/events/:id', () => {
    it('should return 404 for non-existent event', async () => {
      const nonExistentId = new mongoose.Types.ObjectId();
      const response = await request(app).get(`/api/events/${nonExistentId}`);
      expect(response.status).toBe(404);
    });

    it('should return the event when it exists', async () => {
      // Create a test event
      const createdEvent = await Event.create(sampleEvent);

      const response = await request(app).get(`/api/events/${createdEvent._id}`);
      expect(response.status).toBe(200);
      expect(response.body.event.title).toBe('Test Event');
    });
  });

  describe('POST /api/events', () => {
    it('should create a new event', async () => {
      const response = await request(app)
        .post('/api/events')
        .send(sampleEvent);

      expect(response.status).toBe(201);
      expect(response.body.event.title).toBe('Test Event');
      
      // Verify event was saved to database
      const events = await Event.find();
      expect(events.length).toBe(1);
      expect(events[0].title).toBe('Test Event');
    });

    it('should return 400 for invalid event data', async () => {
      // Missing required fields
      const invalidEvent = {
        title: 'Invalid Event',
        // Missing description, date, time, location, category
      };

      const response = await request(app)
        .post('/api/events')
        .send(invalidEvent);

      expect(response.status).toBe(400);
      expect(response.body.error).toBeDefined();
    });
  });

  describe('PUT /api/events/:id', () => {
    it('should update an existing event', async () => {
      // Create a test event
      const createdEvent = await Event.create(sampleEvent);

      // Update the event
      const updatedData = {
        title: 'Updated Event Title',
        description: 'Updated description',
      };

      const response = await request(app)
        .put(`/api/events/${createdEvent._id}`)
        .send(updatedData);

      expect(response.status).toBe(200);
      expect(response.body.event.title).toBe('Updated Event Title');
      expect(response.body.event.description).toBe('Updated description');
      
      // Verify event was updated in database
      const updatedEvent = await Event.findById(createdEvent._id);
      expect(updatedEvent?.title).toBe('Updated Event Title');
      expect(updatedEvent?.description).toBe('Updated description');
    });

    it('should return 404 for non-existent event', async () => {
      const nonExistentId = new mongoose.Types.ObjectId();
      const response = await request(app)
        .put(`/api/events/${nonExistentId}`)
        .send({ title: 'Updated Title' });

      expect(response.status).toBe(404);
    });
  });

  describe('DELETE /api/events/:id', () => {
    it('should delete an existing event', async () => {
      // Create a test event
      const createdEvent = await Event.create(sampleEvent);

      const response = await request(app).delete(`/api/events/${createdEvent._id}`);
      expect(response.status).toBe(200);
      
      // Verify event was deleted from database
      const events = await Event.find();
      expect(events.length).toBe(0);
    });

    it('should return 404 for non-existent event', async () => {
      const nonExistentId = new mongoose.Types.ObjectId();
      const response = await request(app).delete(`/api/events/${nonExistentId}`);
      expect(response.status).toBe(404);
    });
  });

  describe('POST /api/events/:id/register', () => {
    it('should register for an event', async () => {
      // Create a test event
      const createdEvent = await Event.create(sampleEvent);

      const response = await request(app)
        .post(`/api/events/${createdEvent._id}/register`)
        .send({ userId: new mongoose.Types.ObjectId() });

      expect(response.status).toBe(200);
      
      // Verify registration count was incremented
      const updatedEvent = await Event.findById(createdEvent._id);
      expect(updatedEvent?.registeredCount).toBe(1);
    });

    it('should return 400 when event is at capacity', async () => {
      // Create a test event at capacity
      const eventAtCapacity = await Event.create({
        ...sampleEvent,
        maxAttendees: 5,
        registeredCount: 5,
      });

      const response = await request(app)
        .post(`/api/events/${eventAtCapacity._id}/register`)
        .send({ userId: new mongoose.Types.ObjectId() });

      expect(response.status).toBe(400);
      expect(response.body.error.message).toContain('capacity');
    });
  });
});