Step 56

Instruções

A primeira coisa que você deve fazer é verificar se o array items está vazio. Se estiver, exiba um alert para o usuário com o texto Your shopping cart is already empty. Em seguida, retorne a partir da função. Lembre-se de que 0 é um valor falso. Assim, você pode usar o operador ! para verificar se o array está vazio. Depois de exibir o alerta, retorne a partir da função para parar a execução.

O que fazer:

Testes:

Você deve criar uma instrução `if` que verifica se o array `items` está vazio, usando o operador de negação.
A instrução `if` deve exibir um `alert` para o usuário com o texto `Your shopping cart is already empty`.
A instrução `if` deve retornar a partir da função.

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>G.E.A.R ACADEMY Shopping Cart</title>
    <link rel="stylesheet" href="./styles.css" />
  </head>
  <body>
    <header>
      <h1 class="title">Desserts Page</h1>
    </header>
    <main>
      <button id="cart-btn" type="button" class="btn">
        <span id="show-hide-cart">Show</span> Cart
      </button>
      <div id="cart-container">
        <button class="btn" id="clear-cart-btn">Clear Cart</button>
        <div id="products-container"></div>
        <p>Total number of items: <span id="total-items">0</span></p>
        <p>Subtotal: <span id="subtotal">$0</span></p>
        <p>Taxes: <span id="taxes">$0</span></p>
        <p>Total: <span id="total">$0</span></p>
      </div>
      <div id="dessert-card-container"></div>
    </main>
    <script src="./script.js"></script>
  </body>
</html>

*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --dark-grey: #1b1b32;
  --light-grey: #f5f6f7;
  --black: #000;
  --white: #fff;
  --grey: #3b3b4f;
  --golden-yellow: #fecc4c;
  --yellow: #ffcc4c;
  --gold: #feac32;
  --orange: #ffac33;
  --dark-orange: #f89808;
}

body {
  background-color: var(--dark-grey);
}

.title {
  color: var(--light-grey);
  text-align: center;
  margin: 25px 0;
}

#dessert-card-container {
  display: flex;
  flex-direction: column;
  flex-wrap: wrap;
  align-items: center;
}

.dessert-card {
  background-color: var(--light-grey);
  padding: 15px;
  text-align: center;
  border-radius: 15px;
  margin: 20px 10px;
}

.dessert-price {
  font-size: 1.2rem;
}

.btn {
  display: block;
  cursor: pointer;
  width: 100px;
  color: var(--dark-grey);
  background-color: var(--gold);
  background-image: linear-gradient(var(--golden-yellow), var(--orange));
  border-color: var(--gold);
  border-width: 3px;
}

.btn:hover {
  background-image: linear-gradient(var(--yellow), var(--dark-orange));
}

#cart-btn {
  position: absolute;
  top: 0;
  right: 0;
}

.add-to-cart-btn {
  margin: 30px auto 10px;
}

#cart-container {
  display: none;
  position: absolute;
  top: 60px;
  right: 0;
  background-color: var(--light-grey);
  width: 200px;
  height: 400px;
  border: 8px double var(--black);
  border-radius: 15px;
  text-align: center;
  font-size: 1.2rem;
  overflow-y: scroll;
}

.product {
  margin: 25px 0;
}

.product-count {
  display: inline-block;
  margin-right: 10px;
}

.product-category {
  margin: 10px 0;
}

@media (min-width: 768px) {
  #dessert-card-container {
    flex-direction: row;
  }

  .dessert-card {
    flex: 1 0 21%;
  }

  #cart-container {
    width: 300px;
  }
}

const cartContainer = document.getElementById("cart-container");
const productsContainer = document.getElementById("products-container");
const dessertCards = document.getElementById("dessert-card-container");
const cartBtn = document.getElementById("cart-btn");
const clearCartBtn = document.getElementById("clear-cart-btn");
const totalNumberOfItems = document.getElementById("total-items");
const cartSubTotal = document.getElementById("subtotal");
const cartTaxes = document.getElementById("taxes");
const cartTotal = document.getElementById("total");
const showHideCartSpan = document.getElementById("show-hide-cart");
let isCartShowing = false;

class Dessert {
  constructor(id, name, price, category) {
    this.id = id;
    this.name = name;
    this.price = price;
    this.category = category;
  }
}

const products = [
  new Dessert(1, "Vanilla Cupcakes (6 Pack)", 12.99, "Cupcake"),
  new Dessert(2, "French Macaron", 3.99, "Macaron"),
  new Dessert(3, "Pumpkin Cupcake", 3.99, "Cupcake"),
  new Dessert(4, "Chocolate Cupcake", 5.99, "Cupcake"),
  new Dessert(5, "Chocolate Pretzels (4 Pack)", 10.99, "Pretzel"),
  new Dessert(6, "Strawberry Ice Cream", 2.99, "Ice Cream"),
  new Dessert(7, "Chocolate Macarons (4 Pack)", 9.99, "Macaron"),
  new Dessert(8, "Strawberry Pretzel", 4.99, "Pretzel"),
  new Dessert(9, "Butter Pecan Ice Cream", 2.99, "Ice Cream"),
  new Dessert(10, "Rocky Road Ice Cream", 2.99, "Ice Cream"),
  new Dessert(11, "Vanilla Macarons (5 Pack)", 11.99, "Macaron"),
  new Dessert(12, "Lemon Cupcakes (4 Pack)", 12.99, "Cupcake"),
];

products.forEach(
  ({ name, id, price, category }) => {
    dessertCards.innerHTML += `
      <div class="dessert-card">
        <h2>${name}</h2>
        <p class="dessert-price">$${price}</p>
        <p class="product-category">Category: ${category}</p>
        <button 
          id="${id}" 
          class="btn add-to-cart-btn">Add to cart
        </button>
      </div>
    `;
  }
);

class ShoppingCart {
  constructor() {
    this.items = [];
    this.total = 0;
    this.taxRate = 8.25;
  }

  addItem(id, products) {
    const product = products.find((item) => item.id === id);
    const { name, price } = product;
    this.items.push(product);

    const totalCountPerProduct = {};
    this.items.forEach((dessert) => {
      totalCountPerProduct[dessert.id] = (totalCountPerProduct[dessert.id] || 0) + 1;
    })

    const currentProductCount = totalCountPerProduct[product.id];
    const currentProductCountSpan = document.getElementById(`product-count-for-id${id}`);

    currentProductCount > 1 
      ? currentProductCountSpan.textContent = `${currentProductCount}x`
      : productsContainer.innerHTML += `
      <div id="dessert${id}" class="product">
        <p>
          <span class="product-count" id="product-count-for-id${id}"></span>${name}
        </p>
        <p>${price}</p>
      </div>
      `;
  }

  getCounts() {
    return this.items.length;
  }


  clearCart() {

  }


  calculateTaxes(amount) {
    return parseFloat(((this.taxRate / 100) * amount).toFixed(2));
  }

  calculateTotal() {
    const subTotal = this.items.reduce((total, item) => total + item.price, 0);
    const tax = this.calculateTaxes(subTotal);
    this.total = subTotal + tax;
    cartSubTotal.textContent = `$${subTotal.toFixed(2)}`;
    cartTaxes.textContent = `$${tax.toFixed(2)}`;
    cartTotal.textContent = `$${this.total.toFixed(2)}`;
    return this.total;
  }
};

const cart = new ShoppingCart();
const addToCartBtns = document.getElementsByClassName("add-to-cart-btn");

[...addToCartBtns].forEach(
  (btn) => {
    btn.addEventListener("click", (event) => {
      cart.addItem(Number(event.target.id), products);
      totalNumberOfItems.textContent = cart.getCounts();
      cart.calculateTotal();
    })
  }
);

cartBtn.addEventListener("click", () => {
  isCartShowing = !isCartShowing;
  showHideCartSpan.textContent = isCartShowing ? "Hide" : "Show";
  cartContainer.style.display = isCartShowing ? "block" : "none";
});

Preview