TK2-CodeReengineering-Refactor.java

// Author: Ari Supriatna
// Date: Sun, 26 March 2023 23:38

import java.util.ArrayList;

public class Product {
  private String name = "";
  private double price = 0.0;
  private double shippingCost = 0.0;
  private int quantity = 0;
  private static final int MAX_QUANTITY_FOR_DISCOUNT = 50;
  private static final int MAX_TOTAL_PRICE_FOR_DISCOUNT = 500;
  private static final int MIN_QUANTITY_FOR_DISCOUNT = 10;
  private static final int MIN_TOTAL_PRICE_FOR_DISCOUNT = 50;

  public String getName() {
    return name;
  }

  public double getPrice() {
    return price;
  }

  public double getShippingCost() {
    return shippingCost;
  }

  public int getQuantity() {
    return quantity;
  }

  public Product(String name, double price, double shippingCost, int quantity) {
    this.name = name;
    this.price = price;
    this.shippingCost = shippingCost;
    this.quantity = quantity;
  }

  public double getTotalCost() {
    double quantityDiscount = getQuantityDiscount();
    double discount = calculateDiscount(quantityDiscount);

    return calculateTotalCost(discount);
  }

  public String printCost() {
    String output = "";
    output += "Total cost for " + quantity + " " + name + "s is $" + getTotalCost() + "\n";
    output += "Cost per product " + getTotalCost() / quantity + "\n";
    output += "Savings per product " + ((price + shippingCost) - (getTotalCost() / quantity)) + "\n";
    return output;
  }

  private boolean isEligibleForDiscount(int quantity, double price, int maxQuantity, int maxPrice) {
    return (quantity > maxQuantity) || ((quantity * price) > maxPrice);
  }

  private double getQuantityDiscount() {
    double quantityDiscount = 0.0;

    if (isEligibleForDiscount(quantity, price, MAX_QUANTITY_FOR_DISCOUNT, MAX_TOTAL_PRICE_FOR_DISCOUNT)) {
      quantityDiscount = .10;
    } else if (isEligibleForDiscount(quantity, price, MAX_QUANTITY_FOR_DISCOUNT / 2,
        MAX_TOTAL_PRICE_FOR_DISCOUNT / 5)) {
      quantityDiscount = .07;
    } else if (isEligibleForDiscount(quantity, price, MIN_QUANTITY_FOR_DISCOUNT, MIN_TOTAL_PRICE_FOR_DISCOUNT)) {
      quantityDiscount = .05;
    }

    return quantityDiscount;
  }

  private double calculateDiscount(double quantityDiscount) {
    return ((quantity - 1) * quantityDiscount) * price;
  }

  private double calculateTotalCost(double discount) {
    return (quantity * price) + (quantity * shippingCost) - discount;
  }
}

public class Store {
  private ArrayList<Product> products = new ArrayList<Product>();

  public void addProduct(Product newProduct) {
    products.add(newProduct);
  }

  public void showProductDetails() {
    for (Product product : products) {
      System.out.println(product.printCost());
    }
  }

  public static void main(String[] args) {
    Store cornerStore = new Store();

    cornerStore.addProduct(new Product("Pizza", 10.00, 1.00, 52));
    cornerStore.addProduct(new Product("Pizza", 10.00, 1.00, 26));
    cornerStore.addProduct(new Product("Pizza", 10.00, 1.00, 10));

    cornerStore.showProductDetails();
  }
}