Shopping Center With Dictionary

namespace ShoppingCenterWithDic
{
    using System;
    using System.Linq;
    using System.Text;
    using System.Collections.Generic;
    using Wintellect.PowerCollections;

    public class Product
    {
        public string Name { get; private set; }

        public string Producer { get; private set; }

        public decimal Price { get; private set; }

        public Product(string name, string producer, decimal price)
        {
            this.Name = name;
            this.Producer = producer;
            this.Price = price;
        }

        public override string ToString()
        {
            var result = "{" + this.Name + ";" + this.Producer + ";" + this.Price.ToString("0.00") + "}";
            return result;
        }
    }

    public class ShoppingCenter
    {
        private readonly MultiDictionary<string, Product> byName =
            new MultiDictionary<string, Product>(true);

        private readonly MultiDictionary<string, Product> byProducer =
            new MultiDictionary<string, Product>(true);

        private readonly MultiDictionary<Tuple<string, string>, Product> byNameAndProducer =
            new MultiDictionary<Tuple<string, string>, Product>(true);

        private readonly OrderedMultiDictionary<decimal, Product> byPrice =
            new OrderedMultiDictionary<decimal, Product>(true,
                (x, y) => x.CompareTo(y),
                (x, y) => 0);

        public void AddProduct(Product product)
        {
            this.byName[product.Name].Add(product);
            this.byProducer[product.Producer].Add(product);
            this.byNameAndProducer[Tuple.Create(product.Name, product.Producer)].Add(product);
            this.byPrice[product.Price].Add(product);
        }

        public IEnumerable<Product> FindProductsByName(string name)
        {
            var products = this.byName[name];
            return products;
        }

        public IEnumerable<Product> FindProductsByProducer(string producer)
        {
            var products = this.byProducer[producer];
            return products;
        }

        public IEnumerable<Product> FindProductsByPriceRange(decimal min, decimal max)
        {
            var products = this.byPrice.Range(min, true, max, true).Values;
            return products;
        }

        public int DeleteProducts(string producer)
        {
            var products = this.byProducer[producer];
            var count = products.Count;

            foreach (var product in products)
            {
                this.byName[product.Name].Remove(product);
                this.byNameAndProducer[Tuple.Create(product.Name, product.Producer)].Remove(product);
                this.byPrice[product.Price].Remove(product);
            }

            this.byProducer.Remove(producer);

            return count;
        }

        public int DeleteProducts(string name, string producer)
        {
            var nameAndProducer = Tuple.Create(name, producer);

            var products = this.byNameAndProducer[nameAndProducer];
            var count = products.Count;

            foreach (var product in products)
            {
                this.byName[product.Name].Remove(product);
                this.byProducer[product.Producer].Remove(product);
                this.byPrice[product.Price].Remove(product);
            }

            this.byNameAndProducer.Remove(nameAndProducer);

            return count;
        }
    }

    public static class Program
    {
        private static readonly StringBuilder Output = new StringBuilder();

        private static void PrintProducts(IEnumerable<Product> products)
        {
            if (!products.Any())
            {
                Output.AppendLine("No products found");
                return;
            }

            var sorted = products
                                 .OrderBy(x => x.Name)
                                 .ThenBy(x => x.Producer)
                                 .ThenBy(x => x.Price);

            foreach (var product in sorted)
            {
                Output.AppendLine(product.ToString());
            }
        }

        public static void Main()
        {
            var separator = new[] { ' ' };

            var shoppingCenter = new ShoppingCenter();

            foreach (int i in Enumerable.Range(0, int.Parse(Console.ReadLine())))
            {
                var line = Console.ReadLine();
                var splitted = line.Split(separator, 2);
                var name = splitted[0];
                var parameters = splitted[1].Split(';');

                switch (name)
                {
                    case "AddProduct":
                        {
                            var product = new Product(
                                name: parameters[0],
                                price: decimal.Parse(parameters[1]),
                                producer: parameters[2]);

                            shoppingCenter.AddProduct(product);

                            Output.AppendLine("Product added");
                            break;
                        }

                    case "FindProductsByName":
                        {
                            var products = shoppingCenter.FindProductsByName(parameters[0]);

                            PrintProducts(products);

                            break;
                        }

                    case "FindProductsByProducer":
                        {
                            var products = shoppingCenter.FindProductsByProducer(parameters[0]);

                            PrintProducts(products);

                            break;
                        }

                    case "FindProductsByPriceRange":
                        {
                            var products = shoppingCenter.FindProductsByPriceRange(
                                min: decimal.Parse(parameters[0]),
                                max: decimal.Parse(parameters[1]));

                            PrintProducts(products);

                            break;
                        }

                    case "DeleteProducts":
                        {
                            int deletedCount;

                            switch (parameters.Length)
                            {
                                case 1:
                                    deletedCount = shoppingCenter.DeleteProducts(
                                        producer: parameters[0]);

                                    break;
                                case 2:
                                    deletedCount = shoppingCenter.DeleteProducts(
                                        name: parameters[0],
                                        producer: parameters[1]);

                                    break;
                                default:
                                    throw new ArgumentException("DeleteProducts");
                            }

                            if (deletedCount == 0)
                            {
                                Output.AppendLine("No products found");
                                break;
                            }

                            Output.AppendLine(deletedCount + " products deleted");

                            break;
                        }

                    default:
                        throw new ArgumentException("Invalid command: " + name);
                }
            }

            Console.Write(Output);
        }
    }
}