using System;
using System.Windows.Forms;

namespace Science.Mathematics.Calculus
{
    /// <summary>
    /// Adaptive multidimensional Monte Carlo integration.
    /// </summary>
    public class IntegrationMultiD
    {
        private Science.Mathematics.Function.DoubleAToDouble del;
        public IntegrationMultiD()
        {
        }
        public Science.Mathematics.Function.DoubleAToDouble Function
        {
            set { del = value; }
        }

        public IntegrationMultiD(Science.Mathematics.Function.DoubleAToDouble f)
        {
            del = f;
        }

        public void Compute()
        {
            Science.Mathematics.NumericalRecipes.RandomNumbers.Vegas obj
            = new Science.Mathematics.NumericalRecipes.RandomNumbers.Vegas();

            if (Science.Net.Check())
            {
                obj.Dummy = idum;
                obj.vegas(input, input.Length / 2, del, 0, nc, 5, 0);

                tgral = obj.BestEstimation;
                sd = obj.StandardDeviation;
                chi2a = obj.ChiSquare;
                result = obj.Result;
            }
            else
            {
                try { throw new Exception(); }
                catch (Exception)
                {
                    MessageBox.Show("Please support our authors.",
                        "Invalid user", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }

        private double[] input, from, to;
        private bool boolfrom = false, boolto = false;
        public double[] From
        {
            set { from = value; boolfrom = true; if (boolfrom & boolto) Set(); }
        }
        public double[] To
        {
            set { to = value; boolto = true; if (boolfrom & boolto) Set(); }
        }
        private void Set()
        {
            input = new double[2 * to.Length];
            for (int k = 0; k < to.Length; k++)
            {
                input[k] = from[k];
                input[to.Length + k] = to[k];
            }
        }

        private ulong nc = 100000;
        public ulong NumberOfCall
        {
            get { return nc; }
            set { nc = value; }
        }

        private long idum = -11;
        public long Seed
        {
            set { idum = value; }
        }

        private double tgral, sd, chi2a;
        private string result;
        public double BestEstimation
        {
            get { return tgral; }
        }
        public double StandardDeviation
        {
            get { return sd; }
        }
        public double ChiSQUARE
        {
            get { return chi2a; }
        }
        public string Result
        {
            get { return result; }
        }
    }
}