using System;
namespace hwo.bitworks
{
	public class ADD : MultipleBitsSource
	{

		XOR	xor2,xor3;
		AND and12,andC;
		OR 	or;

		public ADD(LogicBase source1,LogicBase source2,LogicBase carry)
		{
			and12 = new AND(source1,source2);
			xor2 = new XOR(source1,source2);
			andC = new AND(carry,xor2);
			or = new OR(andC,and12);

			xor3 = new XOR(source1,source2,carry);
		}

		public override bool bitValue(int bit)
		{
			switch (bit){
				case 1:
					return or.value();
				case 0:
					return xor3.value();
				default:
					throw new IndexOutOfRangeException(String.Format("ADD supplies 2 bits, but bit #{0} requested",bit));
			}
		}

		public override identity.BitIdentity getBitIdentity(int bit)
		{
			switch (bit){
				case 1:
					return or.identity();
				case 0:
					return xor3.identity();
				default:
					throw new IndexOutOfRangeException(String.Format("ADD supplies 2 bits, but bit #{0} requested",bit));
			}
		}

	}
}