using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using HEAL.Attic;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Optimization;

namespace HeuristicLab.Problems.Modifiers {
  [StorableType("19E56ADE-9700-42A1-A5BD-5553CB841E93")]
  public sealed class ModifiedBasicProblemEvaluationExecutionAlgorithm : BasicAlgorithm {
    public override bool SupportsPause => false;

    [Storable]
    public ProblemModifier NextModifier { get; private set; } //private setters are needed for HEAL.Attic
    [Storable]
    public IScope IndividualScope { get; private set; } //private setters are needed for HEAL.Attic
    [Storable]
    public IRandom Random { get; private set; } //private setters are needed for HEAL.Attic
    [Storable]
    public double[] Qualities { get; private set; } //private setters are needed for HEAL.Attic

    #region Constructors & Cloning
    [StorableConstructor]
    private ModifiedBasicProblemEvaluationExecutionAlgorithm(StorableConstructorFlag _) : base(_) { }
    private ModifiedBasicProblemEvaluationExecutionAlgorithm(ModifiedBasicProblemEvaluationExecutionAlgorithm original, Cloner cloner) : base(original, cloner) {
      IndividualScope = cloner.Clone(original.IndividualScope);
      Random = cloner.Clone(original.Random);
      Qualities = original.Qualities.ToArray();
      NextModifier = cloner.Clone(original.NextModifier);

    }
    public ModifiedBasicProblemEvaluationExecutionAlgorithm(ProblemModifier nextModifier, IScope individualScope, IRandom random) {
      NextModifier = nextModifier;
      IndividualScope = individualScope;
      Random = random;
      Qualities = new[] { double.NaN };
    }

    public override IDeepCloneable Clone(Cloner cloner) {
      return new ModifiedBasicProblemEvaluationExecutionAlgorithm(this, cloner);
    }
    #endregion

    protected override void Run(CancellationToken cancellationToken) {
      var encoding = NextModifier.Encoding;
      var individual = encoding is MultiEncoding multiEncoding
        ? (Individual)new MultiEncodingIndividual(multiEncoding, IndividualScope)
        : (Individual)new SingleEncodingIndividual(encoding, IndividualScope);

      var evaluationTask = Task.Run(() => NextModifier.ModifiedEvaluate(individual, Random), cancellationToken);
      evaluationTask.Wait(cancellationToken);
      Qualities = evaluationTask.Result;
    }
  }
}