using HeuristicLab.Operators;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using HeuristicLab.Common;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Parameters;
using HeuristicLab.Optimization;
using HeuristicLab.PluginInfrastructure;
using HeuristicLab.Analysis;

namespace HeuristicLab.Algorithms.SimulatedAnnealing
{
    [Item("AdaptiveReheatingOperator", "Next to the annealing schedule, a hotter schedule is generated. Whenever a solution is accepted, the temperature of the annealing schedule is used. Whenever a solution is rejected, the temperature of the heating schedule is chosen.")]
    [StorableClass]
    public class AdaptiveReheatingOperator : SingleSuccessorOperator, IReheatingOperator
    {
        #region Strings
        private const string AnnealingOperatorName = "AnnealingOperator";
        private const string LowerTemperatureName = "LowerTemperature";
        private const string IterationsName = "Iterations";
        private const string TemperatureStartIndexName = "TemperatureStartIndex";
        private const string StartTemperatureName = "StartTemperature";
        private const string EndTemperatureName = "EndTemperature";
        private const string TemperatureName = "Temperature";
        private const string MaximumIterationsName = "MaximumIterations";
        private const string InitialTemperatureName = "InitialTemperature";
        private const string IsAcceptedName = "IsAccepted";
        private const string LastAcceptedQualityName = "LastAcceptedQuality";
        private const string MoveQualityName = "MoveQuality";

        private const string ReheatingOperatorName = "ReheatingOperator";
        private const string OtherLowerTemperatureName = "OtherLowerTemperature";

        #endregion

        #region Parameters
        public ILookupParameter<DoubleValue> TemperatureParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[TemperatureName]; }
        }
        public ILookupParameter<DoubleValue> LowerTemperatureParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[LowerTemperatureName]; }
        }
        public ILookupParameter<DoubleValue> StartTemperatureParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[StartTemperatureName]; }
        }
        public ILookupParameter<DoubleValue> EndTemperatureParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[EndTemperatureName]; }
        }
        public ILookupParameter<IntValue> TemperatureStartIndexParameter
        {
            get { return (ILookupParameter<IntValue>)Parameters[TemperatureStartIndexName]; }
        }
        public ILookupParameter<IntValue> IterationsParameter
        {
            get { return (ILookupParameter<IntValue>)Parameters[IterationsName]; }
        }
        public ILookupParameter<IDiscreteDoubleValueModifier> AnnealingOperatorParameter
        {
            get { return (ILookupParameter<IDiscreteDoubleValueModifier>)Parameters[AnnealingOperatorName]; }
        }
        public ILookupParameter<IntValue> MaximumIterationsParameter
        {
            get { return (ILookupParameter<IntValue>)Parameters[MaximumIterationsName]; }
        }
        public ILookupParameter<BoolValue> IsAcceptedParameter
        {
            get { return (ILookupParameter<BoolValue>)Parameters[IsAcceptedName]; }
        }
        public ILookupParameter<DoubleValue> MoveQualityParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[MoveQualityName]; }
        }
        public ILookupParameter<DoubleValue> LastAcceptedQualityParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[LastAcceptedQualityName]; }
        }
        public ILookupParameter<DoubleValue> InitialTemperatureParameter
        {
            get { return (ILookupParameter<DoubleValue>)Parameters[InitialTemperatureName]; }
        }
        private IConstrainedValueParameter<IDiscreteDoubleValueModifier> ReheatingOperatorParameter
        {
            get { return (IConstrainedValueParameter<IDiscreteDoubleValueModifier>)Parameters[ReheatingOperatorName]; }
        }
        private ValueParameter<DoubleValue> OtherLowerTemperatureParameter
        {
            get { return (ValueParameter<DoubleValue>)Parameters[OtherLowerTemperatureName]; }
        }

        #endregion

        public AdaptiveReheatingOperator() : base()
        {
            #region Create parameters
            Parameters.Add(new LookupParameter<DoubleValue>(TemperatureName, "The current temperature."));
            Parameters.Add(new LookupParameter<DoubleValue>(LowerTemperatureName, "The lower bound of the temperature."));
            Parameters.Add(new LookupParameter<IntValue>(IterationsName, "The number of iterations."));
            Parameters.Add(new LookupParameter<IDiscreteDoubleValueModifier>(AnnealingOperatorName, "The operator that cools the temperature."));
            Parameters.Add(new LookupParameter<IntValue>(TemperatureStartIndexName, "The index where the annealing or heating was last changed."));
            Parameters.Add(new LookupParameter<DoubleValue>(StartTemperatureName, "The temperature from which cooling should occur."));
            Parameters.Add(new LookupParameter<DoubleValue>(EndTemperatureName, "The temperature to which should be cooled."));
            Parameters.Add(new LookupParameter<IntValue>(MaximumIterationsName, "The maximum number of iterations which should be processed."));
            Parameters.Add(new LookupParameter<BoolValue>(IsAcceptedName, "Whether the move was accepted or not."));
            Parameters.Add(new LookupParameter<DoubleValue>(LastAcceptedQualityName, "Quality of last accepted solution."));
            Parameters.Add(new LookupParameter<DoubleValue>(MoveQualityName, "The value which represents the quality of a move."));
            Parameters.Add(new LookupParameter<DoubleValue>(InitialTemperatureName, "The initial temperature."));
            Parameters.Add(new ConstrainedValueParameter<IDiscreteDoubleValueModifier>(ReheatingOperatorName, "The operator that reheats the temperature."));
            Parameters.Add(new ValueParameter<DoubleValue>(OtherLowerTemperatureName, "The upper bound of the temperature of the heating schedule.", new DoubleValue(10)));


            foreach (var op in ApplicationManager.Manager.GetInstances<IDiscreteDoubleValueModifier>().OrderBy(x => x.Name))
            {
                ReheatingOperatorParameter.ValidValues.Add((IDiscreteDoubleValueModifier)op);
            }

            #endregion

            Parameterize();
        }

        [StorableConstructor]
        protected AdaptiveReheatingOperator(bool deserializing) : base(deserializing) { }
        protected AdaptiveReheatingOperator(AdaptiveReheatingOperator original, Cloner cloner) : base(original, cloner) { }


        public override IDeepCloneable Clone(Cloner cloner)
        {
            return new AdaptiveReheatingOperator(this, cloner);
        }

        public void Parameterize()
        {
            foreach (var op in ReheatingOperatorParameter.ValidValues)
            {
                op.IndexParameter.ActualName = IterationsName;
                op.IndexParameter.Hidden = true;
                op.StartIndexParameter.Value = null;
                op.StartIndexParameter.ActualName = TemperatureStartIndexName;
                op.EndIndexParameter.ActualName = MaximumIterationsParameter.Name;
                op.ValueParameter.ActualName = TemperatureName;
                op.ValueParameter.Hidden = true;
                op.StartValueParameter.ActualName = StartTemperatureName;
                op.StartValueParameter.Hidden = true;
                op.EndValueParameter.Value = OtherLowerTemperatureParameter.Value;
                op.EndValueParameter.Hidden = true;
            }
        }

        public override IOperation Apply()
        {     
            if(!IsAcceptedParameter.ActualValue.Value || LastAcceptedQualityParameter.ActualValue.Value.Equals(MoveQualityParameter.ActualValue.Value))
            {
                return Heat();
            }else
            {
                return Cool();
            }
        }


        private IOperation Heat()
        {
            return new OperationCollection {
                    ExecutionContext.CreateOperation(ReheatingOperatorParameter.Value),
                    base.Apply()
                };
        }

        private IOperation Cool()
        {
            return new OperationCollection {
                    ExecutionContext.CreateOperation(AnnealingOperatorParameter.ActualValue),
                    base.Apply()
                };
        }
    }
}