Resposta - Exercício 5

Classe Item:

public class Item
{
    private int _stock;
    private double _price;
    public string Name { get; set; }
    public int Stock
    {
        get => _stock;
        set
        {
            if (value < 0)
                throw new ArgumentOutOfRangeException(nameof(Stock), "The stock cannot be negative.");
            _stock = value;
        }
    }
    public double Price
    {
        get => _price;
        set
        {
            if (value < 0)
                throw new ArgumentOutOfRangeException(nameof(Price), "The price cannot be negative.");
            _price = value;
        }
    }
    public bool IsAvailable => Stock > 0;
    public string DetailedDescription => $"Item: {this.Name} - Price: {this.Price:F2} - Stock: {this.Stock}";

    public Item(string name, int stock, double price)
    {
        Name = name;
        Stock = stock;
        Price = price;
    }
}

Classe Menu:

public class Menu
{
    private readonly List<Item> _items = new List<Item>();

    public void AddItem(Item item)
    {
        _items.Add(item);
    }

    public void ShowItems()
    {
        Console.WriteLine("Menu items:");
        foreach (Item item in _items)
        {
            Console.WriteLine(item.DetailedDescription);
        }
        Console.WriteLine();
    }
}

Classe Table:

public class Table
{
    public int Number { get; set; }
    public bool Reserved { get; set; } = false;

    public Table(int number)
    {
        Number = number;
    }

    public void ReserveTable()
    {
        Reserved = true;
        Console.WriteLine($"Table {Number} successfully reserved!\n");
    }
}

Classe Restaurant:

public class Restaurant
{
    public string Name { get; set; }
    public Menu Menu;
    public List<Table> Tables = new List<Table>();

    public Restaurant(string name, Menu menu, List<Table> tables)
    {
        Name = name;
        Menu = menu;
        Tables = tables;
    }

    public void ShowAvailableTables()
    {
        foreach (Table table in Tables)
        {
            if (!table.Reserved)
            {
                Console.WriteLine($"Table {table.Number} is available.");
            }
        }
        Console.WriteLine();
    }
}

Classe Order:

public class Order
{
    public int OrderNumber { get; set; }
    public double Price { get; }
    public Item Item { get; set; }
    public Table Table { get; set; }
    public string DetailedDescription => $"Order: {this.OrderNumber} - Item {this.Item.Name} - Table {this.Table.Number}";

    public Order(int orderNumber, Item item, Table table)
    {
        if (!item.IsAvailable)
            throw new InvalidOperationException($"Item '{item.Name}' is out of stock.");

        OrderNumber = orderNumber;
        Item = item;
        Table = table;
        Price = item.Price;

        Item.Stock--;
    }
}

Instâncias:

Item burger = new Item("Cheese Burger", 12, 15.90);
Item soda = new Item("Coca-Cola", 25, 6.50);
Item fries = new Item("French Fries", 8, 9.00);

Menu menu = new Menu();
menu.AddItem(burger);
menu.AddItem(soda);
menu.AddItem(fries);
menu.ShowItems();

Table table1 = new Table(1);
Table table2 = new Table(2);
Table table3 = new Table(3);
table1.ReserveTable();
table3.ReserveTable();

Restaurant restaurant = new Restaurant("Burger House", menu, new List<Table> { table1, table2, table3 });
restaurant.ShowAvailableTables();

Order order = new Order(1, burger, table1);
Console.WriteLine(order.DetailedDescription);