minishop смена цены товара в зависимости от кол-ва налету

<div id="msCart">
    {if !count($products)}
        {'ms2_cart_is_empty' | lexicon}
    {else}
        <div class="cart">
            <h2>Вы добавили товар в корзину</h2>
            <div class="cart-title py-4 row">
                <div class="cart-title-img col-md-3"></div>
                <div class="cart-title-name col-md-3">Наименование товара</div>
                <div class="cart-title-amount text-center col-md-2">Кол-во</div>
                <div class="cart-title-price col-md-3">Цена</div>
            </div>

                {foreach $products as $product}
                    <div id="{$product.key}" class="cart-item mb-3 row">
                        <div class="cart-item-img col-md-3">
                            {if $product.thumb?}
                                <img src="{$product.image}" alt="{$product.pagetitle}" title="{$product.pagetitle}"/>
                            {else}
                                <img src="{'assets_url' | option}components/minishop2/img/web/ms2_small.png"
                                     srcset="{'assets_url' | option}components/minishop2/img/web/ms2_small@2x.png 2x"
                                     alt="{$product.pagetitle}" title="{$product.pagetitle}"/>
                            {/if}
                        </div>
                        <div class="cart-item-name col-md-3">
                            {if $product.id?}
                                <a href="{$product.id | url}">{$product.pagetitle} </a>
                            {else}
                                {$product.name}
                            {/if}
                            {if $product.options?}
                                <div class="small">
                                    {$product.options | join : '; '}
                                </div>
                            {/if}
                        </div>
                        
                        
                        <div class="cart-item-amount col-md-2">
                            <form method="post" class="ms2_form form-inline" role="form">
                                <input type="hidden" name="key" value="{$product.key}"/>
                                <div class="form-group">
                                    <span class="minus">-</span>
                                        <input type="number" name="count" value="{$product.count}" class="number" step="{$product.count_add[0]=='' ? '1':$product.count_add[0]}" min="{$product.min_count[0]=='' ? '1':$product.min_count[0]}" />
                                    <span class="plus">+</span>
                                           
                                    <button class="btn btn-default" type="submit" name="ms2_action" value="cart/change">
                                        <i class="glyphicon glyphicon-refresh"></i>
                                    </button>
                                </div>
                            </form>
                        </div>
                        
                        <div class="cart-item-price col-md-3">
                           <span class="mssaleprice-cost"><span>{$product.price}</span> {'ms2_frontend_currency' | lexicon}</span>
                            {if $product.old_price?}
                            <span class="old_price">{$product.old_price}</span> {'ms2_frontend_currency' | lexicon}
                                {/if}
                        </div>
                        
                        <div class="cart-item-delete text-center col-md-1">
                            <form method="post" class="ms2_form">
                                <input type="hidden" name="key" value="{$product.key}">
                                <button class="fa-layers fa-fw" type="submit" name="ms2_action" value="cart/remove">
                                	<i class="fa-inverse fas fa-times" data-fa-transform="shrink-6"></i>
                                </button>
                            </form>
                        </div>
                        
                    </div>
                {/foreach}

                <!-- Start Cart Total  -->
                        	<div class="row">
                        		<div class="ml-auto col-12 col-md-5 col-xl-3">
                        			<div class="cart-total mb-3">
                        				<span>Итого:</span> 
                        				<span class="ms2_total_cost">{$total.cost} руб.</span>
                        			</div>
                        		</div>
                        	</div>
                <!-- End Cart Total -->
            <div class="cart-item-btns row d-flex flex-wrap mb-4">
                <div class="col-12 order-1 order-md-0 col-md-5 col-xl-3">
                    <div class="cart-back">
                        <a href="[[~2]]">Продолжить покупки</a>
                    </div>
                </div>
                        
                <div class="col-12 col-md-5 col-xl-3 ml-auto mb-3 mb-md-0">
                    <a href="[[~32]]" class="btn-submit">Оформить заказ</a>
                </div>
            </div>
            <!-- -->
        </div>
        <form method="post">
            <button class="btn btn-default" type="submit" name="ms2_action" value="cart/clean">
                <i class="glyphicon glyphicon-remove"></i> {'ms2_cart_clean' | lexicon}
            </button>
        </form>
    {/if}
</div>