using System;
using sharp.extensions;
namespace BigInt
{
	public class Integer: IntBase
	{
		public static readonly Integer ZERO = new Integer();
		public static readonly Integer ONE = new Integer(new UInt32[] { 1 });

		public Integer()
		{
			this.RawValue = new UInt32[1];
		}

		public Integer(UInt32[] value)
		{
			this.RawValue = BigIntMath.reduceSigned(value);
		}
		public Integer(byte[] ivalue)
		{
			UInt32[] v = new UInt32[(ivalue.Length + 3) >> 2];
			ivalue = ivalue.Extend(v.Length << 2);

			for (int n = 0; n < v.Length; n++)
			{
				v[n] = BitConverter.ToUInt32(ivalue, n << 2);
			}
			this.RawValue = BigIntMath.reduceSigned(v);
		}
		public Integer(UInt32[] value, IntField field)
		{
			this.RawValue = BigIntMath.reduceSigned(value);
		}
		public Integer(Integer src)
		{
			this.RawValue = src.RawValue;
		}

		public bool Sign(){
			return BigIntMath.sign(rawValue);
		}

		public int Log2(){
			return BigIntMath.log2(rawValue);
		}

		public Integer Pow(int n)
		{
			if (n == 0)
			{
				return ONE;
			}
			else if (n == 1)
			{
				return this;
			}
			else if (n > 1)
			{
				Integer result = this;
				n--;
				while ((n--) > 0)
				{
					result = (result * this);
				}
				return result;
			}
			throw new ArgumentException("Integer.Pow(n): not implemented for negative exponent");
		}

		public Integer Ones()
		{
			UInt32[] result = BigIntMath.ones(rawValue);
			return new Integer(result);
		}

		public Integer Twos()
		{
			UInt32[] result = BigIntMath.twos(rawValue);
			return new Integer(result);
		}


		public static Integer fromHexString(string hex)
		{
			return new Integer(HexString.toBytes(hex).Reverse());
		}

		public override string ToString()
		{
			return String.Format("[{0}: Sign: {2,5} / {1}]", this.GetType().Name, toHexString(), Sign() );
		}



		private Integer __op_add(Integer b)
		{
			int width = (rawValue.Length > b.RawValue.Length ? rawValue.Length : b.RawValue.Length) + 1;
			UInt32[] v = BigIntMath.extendSigned(rawValue, width);
			UInt32[] vb = BigIntMath.extendSigned(b.RawValue, width);
			return new Integer(BigIntMath.reduceSigned(BigIntMath.add(v,vb)));
		}
		private Integer __op_sub(Integer b)
		{
			int width = (rawValue.Length > b.RawValue.Length ? rawValue.Length : b.RawValue.Length) + 1;
			UInt32[] v = BigIntMath.extendSigned(rawValue, width);
			UInt32[] vb = BigIntMath.extendSigned(b.RawValue, width);
			return new Integer(BigIntMath.reduceSigned(BigIntMath.sub(v,vb)));
		}

		private int __op_cmp(Integer b)
		{
			return BigIntMath.cmp(rawValue, b.RawValue);
		}

		private Integer __op_div(Integer b)
		{
			UInt32[] result = BigIntMath.sdiv(rawValue, b.RawValue);
			return new Integer(result);
		}

		private Integer __op_mod(Integer b)
		{
			UInt32[] result = BigIntMath.smod(rawValue, b.RawValue);
			return new Integer(result);
		}

		private Integer __op_mul(Integer b)
		{
			UInt32[] value = BigIntMath.smul(rawValue, b.RawValue);
			return new Integer(value);
		}

		private Integer __op_new(uint[] value)
		{
			return new Integer(value);
		}

		private Integer __op_shl(int b)
		{
			UInt32[] value = BigIntMath.extendSigned(rawValue, RawValue.Length + ((b + 31) >> 5));
			BigIntMath.shl(value,b);
			return new Integer(value);
		}

		private Integer __op_shr(int b)
		{
			UInt32[] value = rawValue.Segment(0);
			BigIntMath.shr(value, b);
			return new Integer(value);
		}

		public static implicit operator Integer(UInteger ui)
		{
			return new Integer( BigIntMath.signedFromUnsigned( ui.RawValue ));
		}
		public static implicit operator Integer(int i)
		{
			return new Integer(new UInt32[]{(UInt32)i});
		}



		public static Integer operator +(Integer a, Integer b)
		{
			return a.__op_add(b);
		}
		public static Integer operator -(Integer a, Integer b)
		{
			return a.__op_sub(b);
		}
		public static Integer operator *(Integer a, Integer b)
		{
			return a.__op_mul(b);
		}

		public static Integer operator /(Integer a, Integer b)
		{
			return a.__op_div(b);
		}
		public static Integer operator %(Integer a, Integer b)
		{
			return a.__op_mod(b);
		}

		public static bool operator <(Integer a, Integer b)
		{
			return a.__op_cmp(b) < 0;
		}
		public static bool operator >(Integer a, Integer b)
		{
			return a.__op_cmp(b) > 0;
		}
		public static bool operator ==(Integer a, Integer b)
		{
			if ((object)a == (object)b)
			{
				return true;
			}
			if (((object)a == null) || ((object)b == null))
			{
				return false;
			}
			return a.__op_cmp(b) == 0;
		}
		public static bool operator !=(Integer a, Integer b)
		{
			return a.__op_cmp(b) != 0;
		}

		public static Integer operator <<(Integer a, int b)
		{
			return a.__op_shl(b);
		}
		public static Integer operator >>(Integer a, int b)
		{
			return a.__op_shr(b);
		}



	}
}