OOPTask6Shop

using System;
using System.Collections.Generic;

namespace OOPTask6Shop
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Shop shop = new Shop();
            shop.Work();
        }
    }

    public class Shop
    {
        private Seller _seller;
        private Client _client;

        public Shop()
        {
            _seller = new Seller(0);
            _client = new Client(500);
        }

        public void Work()
        {
            const char CommandExit = 'q' ;

            bool isWorking = true;

            while (isWorking)
            {
                _client.ShowInfo();
                Console.WriteLine();
                _seller.ShowInfo();
                Console.WriteLine();

                if (_seller.IsEmpty)
                {
                    Console.WriteLine("У продавца больше нет товаров");
                }
                else
                {
                    Product productToBuy = _seller.GetProductToBuy();

                    if (_client.EnoughMoney(productToBuy))
                    {
                        _seller.SellProduct(productToBuy);
                        _client.BuyProduct(productToBuy);
                        Console.WriteLine("Поздравляем с покупкой");
                    }
                    else
                    {
                        Console.WriteLine("У клиента недостаточно денег");
                    }
                }

                Console.WriteLine($"Нажмите любую клавишу или \"{CommandExit}\" для выхода");

                if (Console.ReadKey().KeyChar == CommandExit)
                    isWorking = false;

                Console.Clear();
            }
        }
    }

    public class Product
    {
        private string _title;

        public Product(string title, int cost)
        {
            _title = title;
            Cost = cost;
        }

        public int Cost { get; private set; }

        public void ShowInfo()
        {
            Console.WriteLine($"товар \"{_title}\" стоимостью {Cost}");
        }
    }

    public class Person
    {
        private protected List<Product> Products = new List<Product>();
        private protected int Money;
        private protected string Title;

        public Person(int money)
        {
            Money = money;
        }

        virtual public void ShowInfo()
        {
            Console.WriteLine($"Я {Title} и у меня {Products.Count} товаров.");
            ShowAllProducts();
        }

        private protected void ShowAllProducts()
        {
            int number = 1;

            foreach (Product product in Products)
            {
                Console.Write($"{number++} - ");
                product.ShowInfo();
            }
        }
    }

    public class Seller : Person
    {
        public Seller(int money): base (money)
        {
            Title = "продавец";
            FillProducts();
        }

        public bool IsEmpty => Products.Count == 0;

        public void SellProduct(Product product)
        {
            Products.Remove(product);
            Money += product.Cost;
        }

        public Product GetProductToBuy()
        {
            int indexProduct = 0;
            bool correctIndexValue = false;

            Console.Write("Введите номер товара для покупки: ");

            while (correctIndexValue == false)
            {
                indexProduct = ReadInt() - 1;

                if (indexProduct >= 0 && indexProduct < Products.Count)
                {
                    correctIndexValue = true;
                }
                else
                {
                    Console.Write("Некорректный номер товара, попробуйте еще: ");
                }
            }

            return Products[indexProduct];
        }

        private int ReadInt()
        {
            int inputNumber;

            while (int.TryParse(Console.ReadLine(), out inputNumber) == false)
            {
                Console.Write("Это не число, попробуйте еще раз: ");
            }

            return inputNumber;
        }

        private void FillProducts()
        {
            Random random = new Random();
            Products.Add(new Product("будильник", random.Next(5, 100)));
            Products.Add(new Product("телефон", random.Next(5, 100)));
            Products.Add(new Product("лопатка", random.Next(5, 100)));
            Products.Add(new Product("совочек", random.Next(5, 100)));
            Products.Add(new Product("машинка", random.Next(5, 100)));
            Products.Add(new Product("кукла", random.Next(5, 100)));
            Products.Add(new Product("слюнявчик", random.Next(5, 100)));
            Products.Add(new Product("презерватив", random.Next(5, 100)));
        }
    }

    public class Client : Person
    {
        public Client(int money) : base(money)
        {
            Title = "покупатель";
        }

        public bool EnoughMoney(Product product)
        {
            return Money >= product.Cost;
        }

        public override void ShowInfo()
        {
            base.ShowInfo();
            Console.WriteLine($"У меня в кошельке {Money} рублей");
        }

        public void BuyProduct(Product product)
        {
            Products.Add(product);
            Money -= product.Cost;
        }
    }
}