/*
Math.Iso.Differentiation.cs

24 November 2009 - Adapted from old Dave codebase to generic DTS utility, with 
                   appropriate name change.
 
$Log: Math.Iso.ChannelDifferentiation.cs,v $
Revision 1.3  2007/04/20 17:40:42  Paul Hrissikopoulos
Fixed bad range checking in sample rate property set accessor.

Revision 1.2  2007/02/05 17:17:08  Paul Hrissikopoulos
Finished installing generic channel math framework + basic calculus operations.

Revision 1.1  2007/02/02 22:34:09  Paul Hrissikopoulos
Added framework for DAVE channel math operators.

Copyright © 2007
Diversified Technical Systems, Inc.
All Rights Reserved
*/

using System;
using System.Collections.Generic;
using System.Text;
using DTS.Common.Utilities;
using DTS.Common.Utilities.DotNetProgrammingConstructs;

namespace DTS.Common.Utilities.Math.Iso
{
    ////////////////////////////////////////////////////////////////////////////////
    /// <summary>
    /// Representation of the ISO-based differentiation
    /// System.Collections.Generic.IList of <see cref="double"/>
    /// -based operation.
    /// </summary>
    public class Differentiation : DoubleListOperation
    {
        ////////////////////////////////////////////////////////////////////////////////
        /// <summary>
        /// Get/set the <see cref="double"/> time resolution of this differentiation.
        /// Should probably be the length of one "sample" of digital data seeing as
        /// we're trying to approximate a continuous domain.
        /// </summary>
        public double SampleRate
        {
            get => _SampleRate.Value;
            set => _SampleRate.Value = value;
        }
        private Property<double> _SampleRate
            = new Property<double>(
                typeof(Differentiation).FullName + ".SampleRate",
                0.0,
                false
            );
        ////////////////////////////////////////////////////////////////////////////////

        ////////////////////////////////////////////////////////////////////////////////
        /// <summary>
        /// Initialize an instance of the Differentiation class.
        /// </summary>
        /// 
        /// <param name="domain">
        /// The System.Collection.Generic.IList of <see cref="double"/>s
        /// domain for this operation.
        /// </param>
        /// 
        public Differentiation(IList<double> domain)
            : base(domain)
        {
        }
        ////////////////////////////////////////////////////////////////////////////////

        ////////////////////////////////////////////////////////////////////////////////
        /// <summary>
        /// Initialize an instance of the Iso.ChannelDifferentiation class.
        /// </summary>
        ///
        /// <param name="domain">
        /// The System.Collections.Generic.IList of <see cref="double"/>s
        /// domain for this operation.
        /// </param>
        /// 
        /// <param name="sampleRate">
        /// The <see cref="double"/> sample rate of the data to be differentiated.
        /// </param>
        /// 
        public Differentiation(IList<double> domain, double sampleRate)
            : this(domain)
        {
            try { SampleRate = sampleRate; }
            catch (System.Exception ex)
            {
                throw new Exception("encountered problem constructing " + GetType().FullName, ex);
            }
        }
        ////////////////////////////////////////////////////////////////////////////////

        ////////////////////////////////////////////////////////////////////////////////
        /// <summary>
        /// Get the result of the operation on the
        /// System.Collections.Generic.IList of <see cref="double"/>s
        /// domain representation.
        /// </summary>
        public override IList<double> Range
        {
            get
            {
                try
                {
                    if (null == Domain)
                        throw new ArgumentNullException("attempted to differentiate null domain reference");

                    else if (0 >= SampleRate)
                        throw new ArgumentOutOfRangeException("attempted to differentiate with sample rate <= zero");

                    else if (!(Domain is ICloneable))
                        throw new InvalidCastException("the domain type for " + typeof(Differentiation).FullName + " must be ICloneable");

                    else
                    {
                        var IndexOfLastDomainValue = Domain.Count - 1;
                        var range = ((ICloneable)Domain).Clone() as double[];
                        var deltaT = SampleRate / 12.0;

                        for (var t = 2; t <= IndexOfLastDomainValue - 2; t++)
                            range[t] = ((Domain[t + 1] - Domain[t - 1]) * 8
                                                        - Domain[t + 2] + Domain[t - 2]) * deltaT;
                        Domain[IndexOfLastDomainValue - 1] = 0;
                        Domain[IndexOfLastDomainValue] = 0;
                        Domain[0] = 0;
                        Domain[1] = 0;

                        return range;
                    }
                }

                catch (System.Exception ex)
                {
                    throw new Exception("encountered problem doing " + GetType().FullName + " operation", ex);
                }
            }
        }
        ////////////////////////////////////////////////////////////////////////////////
    }
    ////////////////////////////////////////////////////////////////////////////////
}