using System;
using System.Runtime.Serialization;

namespace Tanshu.Accounts.Contracts
{
    public class BillItemKey
    {
        //Old = 0, New = 1, Modifiers = 2+
        public BillItemKey(int ProductID, int KotID)
        {
            this.ProductID = ProductID;
            this.KotID = KotID;
        }

        public int ProductID { get; private set; }
        public int KotID { get; private set; }

        public override int GetHashCode()
        {
            return ProductID.GetHashCode() ^ KotID.GetHashCode();
        }
        public override bool Equals(object obj)
        {
            if (obj is BillItemKey)
                return (this == (BillItemKey)obj);
            else
                return false;
        }
        public override string ToString()
        {
            return string.Format("{0} - {1}", ProductID, KotID);
        }

        public static bool operator ==(BillItemKey a, BillItemKey b)
        {
            if (object.ReferenceEquals(null, a))
                return object.ReferenceEquals(null, b);

            if (!(a is BillItemKey))
                return false;
            if (!(b is BillItemKey))
                return false;

            return a.ProductID == b.ProductID && a.KotID == b.KotID;
        }
        public static bool operator !=(BillItemKey a, BillItemKey b)
        {
            return !(a == b);
        }
    }
}