using System;

namespace Psychlops
{


	public abstract class Matrix
	{
		public abstract double this[int row, int col]
		{
			get;
			set;
		}

		/*
		public static Matrix operator +(Matrix m, double d)
		{
			return new Internal.MatrixExpression();
		}
		*/
	}


	namespace Internal
	{

		public class MatrixImplementation : Matrix
		{
			internal double[] elements;
			readonly int nrow, ncol;

			public MatrixImplementation(int dnrow, int dncol)
			{
				nrow = dnrow;
				ncol = dncol;
				elements = new double[nrow * ncol];
			}

			public override double this[int row, int col]
			{
				get
				{
					return elements[(row - 1) * ncol + (col - 1)];
				}
				set
				{
					elements[(row - 1) * ncol + (col - 1)] = value;
				}
			}
		}

		public class MatrixExpression : Matrix
		{
			MatrixImplementation imp;
			readonly int nrow, ncol;
			readonly int drow, dcol;
			
			public MatrixExpression(MatrixImplementation target, int ddrow, int ddcol, int dnrow, int dncol)
			{
				nrow = dnrow;
				ncol = dncol;
				drow = ddrow;
				dcol = ddcol;
				imp = target;
			}

			public override double this[int row, int col]
			{
				get
				{
					return imp.elements[(row - drow) * ncol + (col - dcol)];
				}
				set
				{
					imp.elements[(row - drow) * ncol + (col - dcol)] = value;
				}
			}
		}
	}

}