document.addEventListener('DOMContentLoaded', () => {
    if (window.bootstrap) {
        document.querySelectorAll('.toast').forEach((element) => {
            const toast = new bootstrap.Toast(element);
            toast.show();
        });
    }

    const catalogNode = document.getElementById('catalog-data');
    const customerSelect = document.getElementById('customer_id');
    const productSelect = document.getElementById('product_id');
    const qtyInput = document.getElementById('qty');
    const submitButton = document.getElementById('submit-order-btn');
    const hintBox = document.getElementById('sales-order-hint');

    if (!catalogNode || !customerSelect || !productSelect || !qtyInput) {
        return;
    }

    let catalog = {};
    try {
        catalog = JSON.parse(catalogNode.textContent || '{}');
    } catch (error) {
        console.error('Failed to parse catalog JSON', error);
    }

    const summaryCustomer = document.getElementById('summary-customer');
    const summaryBranch = document.getElementById('summary-branch');
    const summaryPrice = document.getElementById('summary-price');
    const summaryStock = document.getElementById('summary-stock');
    const summaryMargin = document.getElementById('summary-margin');
    const summaryTotal = document.getElementById('summary-total');

    const formatMoney = (value) => `${Number(value).toFixed(2)} ر.س`;

    const getSelectedCustomer = () => catalog[customerSelect.value] || null;
    const getSelectedProduct = () => {
        const current = getSelectedCustomer();
        if (!current) return null;
        return current.items.find((item) => String(item.product_id) === productSelect.value) || null;
    };

    const resetSummary = () => {
        summaryCustomer.textContent = '—';
        summaryBranch.textContent = '—';
        summaryPrice.textContent = '—';
        summaryStock.textContent = '—';
        summaryMargin.textContent = '—';
        summaryTotal.textContent = '—';
    };

    const updateProducts = () => {
        const current = getSelectedCustomer();
        productSelect.innerHTML = '';
        if (!current) {
            productSelect.disabled = true;
            productSelect.innerHTML = '<option value="">اختر العميل أولاً</option>';
            resetSummary();
            hintBox.textContent = 'اختر عميلاً لعرض الأصناف المسموح بها له. إذا كانت الكمية المطلوبة أكبر من المتاح سيظهر تنبيه ويتم تعطيل الإرسال.';
            submitButton.disabled = false;
            return;
        }

        summaryCustomer.textContent = current.customer_name;
        summaryBranch.textContent = current.branch_name;
        productSelect.disabled = false;
        productSelect.innerHTML = '<option value="">اختر الصنف</option>';
        current.items.forEach((item) => {
            const option = document.createElement('option');
            option.value = item.product_id;
            option.textContent = `${item.product_name} — ${item.sku}`;
            productSelect.appendChild(option);
        });
        resetCalculatedFields();
    };

    const resetCalculatedFields = () => {
        summaryPrice.textContent = '—';
        summaryStock.textContent = '—';
        summaryMargin.textContent = '—';
        summaryTotal.textContent = '—';
        submitButton.disabled = false;
    };

    const updateSummary = () => {
        const product = getSelectedProduct();
        const qty = Number(qtyInput.value || 0);
        if (!product) {
            resetCalculatedFields();
            return;
        }

        const price = Number(product.special_price || 0);
        const margin = price - Number(product.cost_price || 0);
        const total = qty > 0 ? qty * price : 0;
        summaryPrice.textContent = formatMoney(price);
        summaryStock.textContent = `${Number(product.stock_qty).toFixed(0)} ${product.unit}`;
        summaryMargin.textContent = formatMoney(margin);
        summaryTotal.textContent = formatMoney(total);

        if (qty > Number(product.stock_qty)) {
            hintBox.textContent = 'الكمية المطلوبة تتجاوز المخزون الحالي. خفّض الكمية أو حدّث المخزون أولاً.';
            hintBox.className = 'alert alert-warning border mt-4 mb-0 small';
            submitButton.disabled = true;
        } else {
            hintBox.textContent = 'السعر الخاص تم تطبيقه تلقائياً بناءً على العميل والصنف المحدد.';
            hintBox.className = 'alert alert-light border mt-4 mb-0 small';
            submitButton.disabled = false;
        }
    };

    customerSelect.addEventListener('change', updateProducts);
    productSelect.addEventListener('change', updateSummary);
    qtyInput.addEventListener('input', updateSummary);
    updateProducts();
});