Step 47

Instruções

Por causa do modo como os computadores armazenam e trabalham com números, cálculos envolvendo números decimais podem resultar em algum comportamento estranho. Por exemplo, 0.1 + 0.2 não é igual a 0.3. Isso ocorre porque os computadores armazenam números decimais como frações binárias. Algumas frações binárias não podem ser representadas exatamente como frações decimais. Queremos limpar o resultado numérico do cálculo. Envolva o cálculo entre parênteses (não inclua a instrução return!) e chame o método .toFixed() nele. Passe o número 2 para o método .toFixed() como um argumento. Isso arredondará o número para duas casas decimais e retornará uma string.

O que fazer:

Testes:

Você deve envolver o cálculo de entre parênteses.
Você deve chamar o método `.toFixed()` no cálculo.
Você deve passar o número `2` para o método `.toFixed()` como um argumento.

<!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;
  }


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


  calculateTotal() {
    const subTotal = this.items.reduce((total, item) => total + item.price, 0);
  }
};

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();
    })
  }
);

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

Preview