controllers/reviewController.js

const Review = require('../models/reviewModel');
const Product = require('../models/productModel');

// create a review
exports.createReview = async (req, res) => {
  try {
    const { product, rating, review } = req.body;

    // Ensure product exists
    const existingProduct = await Product.findById(product);
    if (!existingProduct) {
      return res.status(400).json({ message: 'Invalid product ID' });
    }

    // Prevent duplicate reviews by same user
    const existingReview = await Review.findOne({
      product,
      user: req.user._id,
    });
    if (existingReview) {
      return res
        .status(400)
        .json({ message: 'You already reviewed this product' });
    }

    // Create review
    const newReview = await Review.create({
      product,
      user: req.user._id,
      rating,
      review,
    });

    res.status(201).json({
      status: 'success',
      data: newReview,
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

// get all reviews
exports.getAllReviews = async (req, res) => {
  try {
    const reviews = await Review.find().populate({
      path: 'product',
      select: 'nameEn nameAr price imageCover',
    });

    res.status(200).json({
      status: 'success',
      results: reviews.length,
      data: reviews,
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

// get all reviews for a product
exports.getProductReviews = async (req, res) => {
  try {
    const reviews = await Review.find({ product: req.params.productId });

    res.status(200).json({
      status: 'success',
      results: reviews.length,
      data: reviews,
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

// Update a review
exports.updateReview = async (req, res) => {
  try {
    const review = await Review.findById(req.params.id);

    if (!review) {
      return res.status(404).json({ message: 'Review not found' });
    }

    // Only review owner can edit
    if (review.user.toString() !== req.user._id.toString()) {
      return res.status(403).json({ message: 'Not authorized' });
    }

    const updated = await Review.findByIdAndUpdate(
      req.params.id,
      { rating: req.body.rating, review: req.body.review },
      { new: true, runValidators: true },
    );

    // Trigger recalculation manually (because findByIdAndUpdate doesn’t trigger post('save'))
    await Review.calcAverageRatings(review.product);

    res.status(200).json({
      status: 'success',
      data: updated,
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

// Delete a review
exports.deleteReview = async (req, res) => {
  try {
    const review = await Review.findById(req.params.id);

    if (!review) {
      return res.status(404).json({ message: 'Review not found' });
    }

    // Only review owner or admin can delete
    if (review.user.toString() !== req.user._id.toString()) {
      return res.status(403).json({ message: 'Not authorized' });
    }

    await Review.findByIdAndDelete(req.params.id);
    await Review.calcAverageRatings(review.product);

    res.status(204).json({ status: 'success', data: null });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};