Store application (buyer, trader, product)

iJunior_C#_Lesson_56

using System;
using System.Collections.Generic;

namespace iJuniorPractice
{
    class Program
    {
        static void Main(string[] args)
        {
            AppController appController = new AppController();
            appController.Play();
        }
    }

    static class Utils
    {
        public static int ReadInt(string message = "")
        {
            int number;
            string input;

            Console.WriteLine(message);
            input = Console.ReadLine();
            
            while (int.TryParse(input, out number) == false)
            {
                Console.WriteLine("Incorrect input. Try again.");
                input = Console.ReadLine();
            }

            return number;
        }

        public static string ReadString(string message = "")
        {
            string input;

            Console.WriteLine(message);
            input = Console.ReadLine();
            
            while (input == "")
            {
                Console.WriteLine("Incorrect input, line is empty. Try again.");
                input = Console.ReadLine();
            }

            return input;
        }
    }

    class AppController
    {
        private const int CommandShowStoreInfo = 1;
        private const int CommandBuyProduct = 2;
        private const int CommandShowBuyerInventory = 3;
        private const int CommandExit = 0;

        public void Play()
        {
            Dictionary<int, Product> productsInStore = new Dictionary<int, Product>
            {
                { 1, new Product(1, 20, "Apple", 5) },
                { 2, new Product(2, 100, "Coconut", 1) },
                { 3, new Product(3, 10, "Cucumber", 10) },
                { 4, new Product(4, 40, "Pineapple", 2) }
            };
            Trader trader = new Trader(100, productsInStore);
            Buyer buyer = new Buyer(1000, new Dictionary<int, Product>());
            bool isWork = true;

            while (isWork)
            {
                ShowMenu();
                int input = Utils.ReadInt("Please enter command: ");

                switch (input)
                {
                    case CommandShowStoreInfo:
                        trader.ShowProducts();
                        break;

                    case CommandBuyProduct:
                        HandleBuyProduct(buyer, trader);
                        break;

                    case CommandShowBuyerInventory:
                        buyer.ShowInfo();
                        break;

                    case CommandExit:
                        isWork = false;
                        break;

                    default:
                        Console.WriteLine("Incorrect input.");
                        break;
                }

                Console.WriteLine("Press any key to continue...");
                Console.ReadKey();
                Console.Clear();
            }

            Console.WriteLine("Exiting...");
        }

        private void ShowMenu()
        {
            Console.WriteLine($"Main Menu:");
            Console.WriteLine($"{CommandShowStoreInfo} - See the products in the shop");
            Console.WriteLine($"{CommandBuyProduct} - Buy a product");
            Console.WriteLine($"{CommandShowBuyerInventory} - Show Inventory");
            Console.WriteLine($"{CommandExit} - Exit");
        }

        private void HandleBuyProduct(Buyer buyer, Trader trader)
        {
            trader.ShowProducts();
            if (buyer.TryToBuyProduct(out int amount, out int productId))
            {
                Product product = trader.GetProductById(productId);
                
                if (product != null && trader.TryToSell(product, amount, buyer))
                {
                    buyer.Buy(amount, product);
                    Console.WriteLine("Purchase successful!");
                }
            }
        }
    }

    class Trade
    {
        protected Trade(int moneyAmount, Dictionary<int, Product> products)
        {
            MoneyAmount = moneyAmount;
            Products = products;
        }
        
        public int MoneyAmount { get; protected set; }
        public Dictionary<int, Product> Products { get; protected set; }
    }

    class Buyer : Trade
    {
        public Buyer(int moneyAmount, Dictionary<int, Product> products) : base(moneyAmount, products)
        {
        }

        public bool TryToBuyProduct(out int amount, out int productId)
        {
            productId = Utils.ReadInt("Please enter product ID: ");
            amount = Utils.ReadInt("Please enter the amount you want to buy: ");

            if (amount <= 0)
            {
                Console.WriteLine("Amount must be greater than zero.");
                return false;
            }
            
            return true;
        }

        public void Buy(int amount, Product product)
        {
            if (MoneyAmount >= product.Price * amount)
            {
                MoneyAmount -= product.Price * amount;
                if (Products.ContainsKey(product.Id))
                {
                    Products[product.Id].IncreaseAmountBy(amount);
                }
                else
                {
                    Products.Add(product.Id, new Product(product.Id, product.Price, product.Name, amount));
                }
            }
            else
            {
                Console.WriteLine("Not enough money.");
            }
        }

        public void ShowInfo()
        {
            Console.WriteLine($"Balance: {MoneyAmount}, Product list:");
            
            if (Products.Count == 0)
            {
                Console.WriteLine("Inventory is empty.");
            }
            else
            {
                foreach (var product in Products.Values)
                {
                    product.GetInfo();
                }
            }
        }
    }

    class Trader : Trade
    {
        public Trader(int moneyAmount, Dictionary<int, Product> products) : base(moneyAmount, products)
        {
        }

        public Product GetProductById(int productId)
        {
            if (Products.TryGetValue(productId, out Product product))
            {
                return product;
            }
            
            Console.WriteLine("Incorrect product id. Try again.");
            return null;
        }

        public bool TryToSell(Product product, int amount, Buyer buyer)
        {
            if (product == null)
            {
                return false;
            }

            if (amount > product.Count)
            {
                Console.WriteLine("Not enough products in stock.");
                return false;
            }

            if (buyer.MoneyAmount < product.Price * amount)
            {
                Console.WriteLine("Buyer does not have enough money.");
                return false;
            }

            product.DecreaseAmountBy(amount);
            MoneyAmount += product.Price * amount;

            if (product.Count == 0)
            {
                Products.Remove(product.Id);
            }

            return true;
        }

        public void ShowProducts()
        {
            if (Products.Count == 0)
            {
                Console.WriteLine("Store is empty.");
            }
            else
            {
                foreach (var product in Products)
                {
                    Console.Write($"{product.Key}. ");
                    product.Value.GetInfo();
                }
            }
        }
    }

    class Product
    {
        public Product(int id, int price, string name, int count)
        {
            Id = id;
            Price = price;
            Name = name;
            Count = count;
        }

        public int Id { get; private set; }
        public int Price { get; private set; }
        public string Name { get; private set; }
        public int Count { get; private set; }

        public void GetInfo()
        {
            Console.WriteLine($"{Name}, Price: {Price}, Count: {Count}");
        }

        public void IncreaseAmountBy(int amount)
        {
            Count += amount;
        }

        public void DecreaseAmountBy(int amount)
        {
            Count -= amount;
        }
    }
}