script.js

var shoppingCart = (function() {
  cart = [];

  function Item(name, price, count) {
      this.name = name;
      this.price = price;
      this.count = count;
  }

  function saveCart() {
      sessionStorage.setItem('shoppingCart', JSON.stringify(cart));
  }

  function loadCart() {
      cart = JSON.parse(sessionStorage.getItem('shoppingCart'));
  }
  if (sessionStorage.getItem("shoppingCart") != null) {
      loadCart();
  }
  //post the cart into PHP
  function postCart() {
      var data = {};
      var noMeja = {};
      // for (var len = sessionStorage.length, i = 0; i < len; i++) {
      //     var key = sessionStorage.key(i);
      //     data[key] = sessionStorage.getItem(key);
      // }
      data = sessionStorage.getItem("shoppingCart");
      noMeja = document.getElementsByName("nomor")[0].value;

      console.log(data);

      //From this point you can post the `data` to your server side
      $.post("./isipesanan.php", {
              data1: data,
              noMeja1: noMeja,

          },
          function(response, status) {
              alert("respons server" + response);
              alert("status server" + status);
          }
      );
  }

  //trigger order now
  $("#order-now").click(postCart);

  var obj = {};
  obj.addItemToCart = function(name, price, count) {
      for (var item in cart) {
          if (cart[item].name === name) {
              cart[item].count++;
              saveCart();
              return;
          }
      }
      var item = new Item(name, price, count);
      cart.push(item);
      saveCart();
  }
  obj.setCountForItem = function(name, count) {
      for (var i in cart) {
          if (cart[i].name === name) {
              cart[i].count = count;
              break;
          }
      }
  };
  obj.removeItemFromCart = function(name) {
      for (var item in cart) {
          if (cart[item].name === name) {
              cart[item].count--;
              if (cart[item].count === 0) {
                  cart.splice(item, 1);
              }
              break;
          }
      }
      saveCart();
  }
  obj.removeItemFromCartAll = function(name) {
      for (var item in cart) {
          if (cart[item].name === name) {
              cart.splice(item, 1);
              break;
          }
      }
      saveCart();
  }
  obj.clearCart = function() {
      cart = [];
      saveCart();
  }
  obj.totalCount = function() {
      var totalCount = 0;
      for (var item in cart) {
          totalCount += cart[item].count;
      }
      return totalCount;
  }
  obj.totalCart = function() {
      var totalCart = 0;
      for (var item in cart) {
          totalCart += cart[item].price * cart[item].count;
      }
      return Number(totalCart.toFixed(2));
  }
  obj.listCart = function() {
      var cartCopy = [];
      for (i in cart) {
          item = cart[i];
          itemCopy = {};
          for (p in item) {
              itemCopy[p] = item[p];
          }
          itemCopy.total = Number(item.price * item.count).toFixed(2);
          cartCopy.push(itemCopy)
      }
      return cartCopy;
  }
  return obj;
})();

$('.add-to-cart').click(function(event) {
  event.preventDefault();
  var name = $(this).data('name');
  var price = Number($(this).data('price'));
  shoppingCart.addItemToCart(name, price, 1);
  displayCart();
});
$('.clear-cart').click(function() {
  shoppingCart.clearCart();
  displayCart();
});
$('.show-cart').on("click", ".delete-item", function(event) {
  var name = $(this).data('name')
  shoppingCart.removeItemFromCartAll(name);
  displayCart();
})
$('.show-cart').on("click", ".minus-item", function(event) {
  var name = $(this).data('name')
  shoppingCart.removeItemFromCart(name);
  displayCart();
})
$('.show-cart').on("click", ".plus-item", function(event) {
  var name = $(this).data('name')
  shoppingCart.addItemToCart(name);
  displayCart();
})
$('.show-cart').on("change", ".item-count", function(event) {
  var name = $(this).data('name');
  var count = Number($(this).val());
  shoppingCart.setCountForItem(name, count);
  displayCart();
});

function displayCart() {
  var cartArray = shoppingCart.listCart();
  var output = "";
  for (var i in cartArray) {
      output += "<tr>" +
          "<td>" + cartArray[i].name + "</td>" +
          "<td>(" + cartArray[i].price + ")</td>" +
          "<td><div class='input-group'><button class='minus-item input-group-addon btn btn-primary' data-name=" + cartArray[i].name + ">-</button>" +
          "<input type='number' class='item-count form-control' data-name='" + cartArray[i].name + "' value='" + cartArray[i].count + "'>" +
          "<button class='plus-item btn btn-primary input-group-addon' data-name=" + cartArray[i].name + ">+</button></div></td>" +
          "<td><button class='delete-item btn btn-danger' data-name=" + cartArray[i].name + ">X</button></td>" +
          " = " +
          "<td>" + cartArray[i].total + "</td>" +
          "</tr>";
  }
  $('.show-cart').html(output);
  $('.total-cart').html(shoppingCart.totalCart());
  $('.total-count').html(shoppingCart.totalCount());
}

displayCart();