/**

 * Invoice.cs

 * 

 */

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using static Sales.Payment;

namespace Sales

{

    delegate double InvoiceDelegate();

    class Invoice

    {

        private double value = 0;

        private PaymentType till;

        public Invoice(double value, PaymentType till)

        {

            this.value = value;

            this.till = till;

            InvoiceDelegate invoiceDelegateReference = this.Rabatt;

            invoiceDelegateReference += this.AddTax;

            invoiceDelegateReference += this.Skonto;

            invoiceDelegateReference();

        }

        public double getFinalResult()

        {            

            return value;

        }

        // Rabatt auf den Netto Preis

        private double Rabatt()

        {

            if (value > 1000.0)

            {

                value *= 0.75;

            }

            else if (value > 500.0)

            {

                value *= 0.85;

            }

            return value;

        }

        // Steuern auf den rabattierten Nettopreis

        private double AddTax()

        {

            value *= 1.19;

            return value;

        }

        // Skonto immer zum Schluss

        private double Skonto()

        {

            switch (till)

            {

                case PaymentType.NOW:

                    value *= 0.97;

                    break;

                case PaymentType.WEEK:

                    value *= 0.98;

                    break;

                case PaymentType.MONTH:

                    value *= 0.99;

                    break;

            }

            return value;

        }

    }

}