const express = require('express');
const rateLimit = require('express-rate-limit');
const helmet = require('helmet');
const cors = require('cors');
const mongoose = require('mongoose');
require('dotenv').config();

const app = express();
const PORT = 7860;
const API_KEY = process.env.API_KEY;
const MONGO_URI = process.env.MONGO_URI;

app.use(express.json());
app.use(helmet());
app.use(cors());

const limiter = rateLimit({
  windowMs: 10 * 60 * 1000,
  max: 100,
  message: { error: 'Too many requests, slow down.' }
});

app.use(limiter);

mongoose.connect(MONGO_URI, {
  useNewUrlParser: true,
  useUnifiedTopology: true
}).then(() => console.log('MongoDB connected'))
  .catch(err => {
    console.error('MongoDB error:', err);
    process.exit(1);
  });

const Ad = mongoose.model('Ad', new mongoose.Schema({
  link: String,
  message: String,
  image: String,
  createdAt: { type: Date, default: Date.now }
}));

function auth(req, res, next) {
  const key = req.headers['x-api-key'];
  if (key !== API_KEY) return res.status(403).json({ error: 'Forbidden' });
  next();
}

app.post('/ads', auth, async (req, res) => {
  const { link, message, image } = req.body;
  if (typeof link !== 'string' || typeof message !== 'string') {
    return res.status(400).json({ error: 'Invalid input' });
  }

  const ad = new Ad({ link, message, image });
  await ad.save();
  res.json({ success: true, data: ad });
});

app.get('/ads', async (req, res) => {
  const ads = await Ad.find().sort({ createdAt: -1 });
  res.json(ads);
});

app.delete('/ads', auth, async (req, res) => {
  const result = await Ad.deleteMany({});
  res.json({ success: true, deleted: result.deletedCount });
});

app.delete('/ads/:id', auth, async (req, res) => {
  try {
    const result = await Ad.findByIdAndDelete(req.params.id);
    if (!result) {
      return res.status(404).json({ error: 'Ad not found' });
    }
    res.json({ success: true, deletedId: req.params.id });
  } catch (err) {
    res.status(400).json({ error: 'Invalid ID' });
  }
});

app.listen(PORT, () => {
  console.log(`Server Active:${PORT}`);
});