using System;

public class Program

{

    public static void Main()

    {

        // Coca-Cola example, 10.6 g sugar per 100 ml

            decimal sugar = 10.6m;

            decimal volume = 0.5m; // 0.5 liter bottle

            decimal basePrice = 5.00m; // price per liter

​

            // California

            var californiaBottle = new Bottle(new CaliforniaTaxStrategy());

            var priceCA = californiaBottle.GetFinalPrice(basePrice, volume, sugar);

            Console.WriteLine($"California: {priceCA:F2} USD");

​

            // Oregon

            var oregonBottle = new Bottle(new OregonTaxStrategy());

            var priceOR = oregonBottle.GetFinalPrice(basePrice, volume, sugar);

            Console.WriteLine($"Oregon: {priceOR:F2} USD");

​

            // New York

            var newYorkBottle = new Bottle(new NewYorkTaxStrategy());

            var priceNY = newYorkBottle.GetFinalPrice(basePrice, volume, sugar);

            Console.WriteLine($"New York: {priceNY:F2} USD");

​

            // Poland

            var polandBottle = new Bottle(new PolandTaxStrategy());

            var pricePL = polandBottle.GetFinalPrice(basePrice, volume, sugar);

            Console.WriteLine($"Poland: {pricePL:F2} PLN");

​

            // Germany

            var germanyBottle = new Bottle(new GermanyTaxStrategy());

            var priceDE = germanyBottle.GetFinalPrice(basePrice, volume, sugar);

            Console.WriteLine($"Germany: {priceDE:F2} €");

    }

    // Strategy interface

    public interface ITaxStrategy

    {

        decimal CalculateFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml);

    }

​

    // California (soda tax + sales tax)

    public class CaliforniaTaxStrategy : ITaxStrategy

    {

        private const decimal SodaTaxPerLiter = 0.34m; // example soda tax per liter

        private const decimal SalesTaxRate = 0.075m;   // 7.5% sales tax

​

        public decimal CalculateFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml)

        {

            decimal price = basePricePerLiter * volumeLiters;

​

            // Apply soda tax if sugar > 0

            if (sugarGramsPer100ml > 0)

            {

                decimal sodaTax = SodaTaxPerLiter * volumeLiters;

                price += sodaTax;

            }

​

            // Apply sales tax

            price *= 1 + SalesTaxRate;

​

            return price;

        }

    }

​

    // Oregon (no soda tax, no sales tax)

    public class OregonTaxStrategy : ITaxStrategy

    {

        public decimal CalculateFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml)

        {

            decimal price = basePricePerLiter * volumeLiters;

            // No soda tax

            // No sales tax

            return price;

        }

    }

​

    // New York (sales tax, no soda tax)

    public class NewYorkTaxStrategy : ITaxStrategy

    {

        private const decimal SalesTaxRate = 0.08875m; // 8.875% sales tax (NYC example)

​

        public decimal CalculateFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml)

        {

            decimal price = basePricePerLiter * volumeLiters;

​

            // No soda tax

​

            // Apply sales tax

            price *= 1 + SalesTaxRate;

​

            return price;

        }

    }

​

    // Poland (sugar tax + VAT)

    public class PolandTaxStrategy : ITaxStrategy

    {

        public decimal CalculateFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml)

        {

            decimal price = basePricePerLiter * volumeLiters;

​

            // Sugar tax

            decimal sugarTaxPerLiter = 0.50m;

            if (sugarGramsPer100ml > 5)

            {

                var extraSugar = sugarGramsPer100ml - 5;

                sugarTaxPerLiter += extraSugar * 0.05m;

            }

            decimal sugarTax = sugarTaxPerLiter * volumeLiters;

            price += sugarTax;

​

            // VAT 23%

            price *= 1.23m;

​

            return price;

        }

    }

​

    // Germany (VAT only)

    public class GermanyTaxStrategy : ITaxStrategy

    {

        public decimal CalculateFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml)

        {

            decimal price = basePricePerLiter * volumeLiters;

​

            // VAT 19%

            price *= 1.19m;

​

            return price;

        }

    }

​

    // Context

    public class Bottle

    {

        private readonly ITaxStrategy _taxStrategy;

​

        public Bottle(ITaxStrategy taxStrategy)

        {

            _taxStrategy = taxStrategy;

        }

​

        public decimal GetFinalPrice(decimal basePricePerLiter, decimal volumeLiters, decimal sugarGramsPer100ml)

        {

            return _taxStrategy.CalculateFinalPrice(basePricePerLiter, volumeLiters, sugarGramsPer100ml);

        }

    }

}