Validate quantity inputs

public/javascripts/expressCart.js

@@ -305,6 +305,14 @@ $(document).ready(function (){
         });
     });
 
+    $('#product_quantity').on('keyup', function(e){
+        checkMaxQuantity(e, $('#product_quantity'));
+    });
+
+    $('.cart-product-quantity').on('keyup', function(e){
+        checkMaxQuantity(e, $('.cart-product-quantity'));
+    });
+
     $('.cart-product-quantity').on('focusout', function(e){
         cartUpdate($(e.target));
     });
@@ -391,6 +399,20 @@ $(document).ready(function (){
     }
 });
 
+function checkMaxQuantity(e, element){
+    if($('#maxQuantity').length){
+        if(e.keyCode === 46 || e.keyCode === 8){
+            return;
+        }
+        if(parseInt($(e.target).val()) > parseInt($('#maxQuantity').val())){
+            const qty = element.val();
+            e.preventDefault();
+            element.val(qty.slice(0, -1));
+            showNotification(`Exceeds maximum quantity: ${$('#maxQuantity').val()}`, 'warning', false);
+        }
+    }
+}
+
 function deleteFromCart(element){
     $.ajax({
         method: 'POST',

views/layouts/layout.hbs

@@ -166,6 +166,7 @@
         <input type="hidden" id="cartCheckout" value="{{checkout}}">
         <input type="hidden" id="cartTheme" value="{{@root.config.theme}}">
         <input type="hidden" id="currencySymbol" value="{{@root.config.currencySymbol}}">
+        {{#if @root.config.maxQuantity}} <input type="hidden" id="maxQuantity" value="{{@root.config.maxQuantity}}">{{/if}}
 		<div id="notify_message"></div>
 		{{#if showFooter}}
             <footer class="footer">