document.addEventListener('DOMContentLoaded', () => {
    let cart = [];
    const cartItemsContainer = document.getElementById('cart-items');
    const cartTotalPrice = document.getElementById('cart-total-price');
    const checkoutBtn = document.getElementById('checkout-btn');
    const mobileCartBtn = document.getElementById('mobile-cart-btn');

    // Helper for currency formatting
    function formatCurrency(amount) {
        // Fallback if settings not defined
        const settings = (typeof COMPANY_SETTINGS !== 'undefined') ? COMPANY_SETTINGS : { currency_symbol: '$', currency_decimals: 2 };
        const symbol = settings.currency_symbol || '$';
        const decimals = parseInt(settings.currency_decimals || 2);
        return symbol + parseFloat(amount).toFixed(decimals);
    }

    // Add to cart
    document.querySelectorAll('.add-to-cart').forEach(button => {
        button.addEventListener('click', (e) => {
            const product = {
                id: e.target.dataset.id,
                name: e.target.dataset.name,
                price: parseFloat(e.target.dataset.price),
                quantity: 1
            };

            const existing = cart.find(item => item.id === product.id);
            if (existing) {
                existing.quantity++;
            } else {
                cart.push(product);
            }

            updateCart();
            showToast(`${product.name} added to cart!`);
        });
    });

    function updateCart() {
        if (cart.length === 0) {
            cartItemsContainer.innerHTML = '<p class="text-center text-muted mt-5">Your cart is empty.</p>';
            cartTotalPrice.innerText = formatCurrency(0);
            checkoutBtn.disabled = true;
            if (mobileCartBtn) mobileCartBtn.innerText = `View Cart (${formatCurrency(0)})`;
            return;
        }

        cartItemsContainer.innerHTML = '';
        let total = 0;
        cart.forEach(item => {
            const itemTotal = item.price * item.quantity;
            total += itemTotal;
            const div = document.createElement('div');
            div.className = 'cart-item';
            div.innerHTML = `
                <div>
                    <div class="cart-item-name">${item.name} x${item.quantity}</div>
                    <div class="text-muted small">${formatCurrency(item.price)} ea</div>
                </div>
                <div class="cart-item-price">${formatCurrency(itemTotal)}</div>
            `;
            cartItemsContainer.appendChild(div);
        });

        cartTotalPrice.innerText = formatCurrency(total);
        checkoutBtn.disabled = false;
        if (mobileCartBtn) mobileCartBtn.innerText = `View Cart (${formatCurrency(total)})`;
    }

    // Checkout
    checkoutBtn.addEventListener('click', () => {
        if (cart.length === 0) return;

        const table_id = new URLSearchParams(window.location.search).get('table') || '1';
        
        // Calculate total
        const totalAmount = cart.reduce((acc, item) => acc + (item.price * item.quantity), 0);

        const orderData = {
            table_number: table_id,
            total_amount: totalAmount,
            // Only send necessary fields
            items: cart.map(item => ({
                product_id: item.id,
                quantity: item.quantity,
                unit_price: item.price
            }))
        };
        
        // Use existing api/order.php
        fetch('api/order.php', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify(orderData)
        })
        .then(res => res.json())
        .then(data => {
            if (data.success) {
                cart = [];
                updateCart();
                showToast('Order placed successfully! Please wait for preparation.', 'success');
            } else {
                showToast('Error: ' + (data.error || 'Unknown error'), 'danger');
            }
        })
        .catch(err => {
            console.error(err);
            showToast('Failed to place order.', 'danger');
        });
    });

    function showToast(message, type = 'dark') {
        const toastContainer = document.getElementById('toast-container');
        if (!toastContainer) return;
        
        const toastId = 'toast-' + Date.now();
        const toastHtml = `
            <div id="${toastId}" class="toast align-items-center text-white bg-${type} border-0" role="alert" aria-live="assertive" aria-atomic="true">
                <div class="d-flex">
                    <div class="toast-body">${message}</div>
                    <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast" aria-label="Close"></button>
                </div>
            </div>
        `;
        toastContainer.insertAdjacentHTML('beforeend', toastHtml);
        const toastElement = document.getElementById(toastId);
        const toast = new bootstrap.Toast(toastElement);
        toast.show();
        toastElement.addEventListener('hidden.bs.toast', () => toastElement.remove());
    }
});