using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Problems.MetaOptimization {
  [StorableClass]
  public class ParameterizedValueConfiguration : ValueConfiguration {
    [Storable]
    protected IItemCollection<IParameterConfiguration> parameterConfigurations = new ItemCollection<IParameterConfiguration>();
    public virtual IItemCollection<IParameterConfiguration> ParameterConfigurations {
      get { return new ReadOnlyItemCollection<IParameterConfiguration>(this.parameterConfigurations); }
      protected set { this.parameterConfigurations = value; }
    }

    public override bool Optimize {
      get { return base.Optimize; }
      set {
        if (this.optimize != value) {
          base.Optimize = value;
          if (optimize) {
            ClearParameterConfigurations();
            PopulateParameterConfigurations(this.actualValue.Value, this.discoverValidValues);
          } else {
            ClearParameterConfigurations();
          }
        }
      }
    }

    public override ConstrainedValue ActualValue {
      get { return base.ActualValue; }
      set {
        ClearParameterConfigurations();
        base.ActualValue = value;
        if (this.Optimize && this.actualValue.Value != null) PopulateParameterConfigurations(this.actualValue.Value, this.discoverValidValues);
      }
    }

    [Storable]
    protected bool discoverValidValues;
    public bool DiscoverValidValues {
      get { return discoverValidValues; }
      set { discoverValidValues = value; }
    }

    public override bool ValuesReadOnly {
      set {
        if (value != this.valuesReadOnly) {
          this.valuesReadOnly = value;
          foreach (var pc in this.parameterConfigurations) {
            pc.ValuesReadOnly = value;
          }
        }
      }
    }

    #region Constructors and Cloning
    [StorableConstructor]
    protected ParameterizedValueConfiguration(bool deserializing) : base(deserializing) { }
    protected ParameterizedValueConfiguration()
      : base() {
      this.ParameterConfigurations = new ItemList<IParameterConfiguration>();
    }
    public ParameterizedValueConfiguration(IItem value, Type valueDataType, bool discoverValidValues)
      : base(value, valueDataType) {
      this.discoverValidValues = discoverValidValues;
    }
    protected ParameterizedValueConfiguration(ParameterizedValueConfiguration original, Cloner cloner)
      : base(original, cloner) {
      this.discoverValidValues = original.discoverValidValues;
      this.ParameterConfigurations = cloner.Clone(original.parameterConfigurations);
    }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new ParameterizedValueConfiguration(this, cloner);
    }
    #endregion

    protected virtual void PopulateParameterConfigurations(IItem item, bool discoverValidValues) {
      var parameterizedItem = item as IParameterizedItem;
      if (parameterizedItem != null) {
        foreach (var childParameter in parameterizedItem.Parameters) {
          IValueParameter valueParameter = childParameter as IValueParameter;
          if (valueParameter != null) {
            var pc = new ParameterConfiguration(valueParameter.Name, valueParameter, discoverValidValues);
            this.parameterConfigurations.Add(pc);
          }
        }
      }
    }

    protected virtual void ClearParameterConfigurations() {
      parameterConfigurations.Clear();
    }

    public override string ParameterInfoString {
      get {
        StringBuilder sb = new StringBuilder();
        if ((this.Optimize) && this.ParameterConfigurations.Count > 0) {
          var parameterInfos = new List<string>();
          foreach (var pc in this.ParameterConfigurations) {
            if (pc.Optimize) parameterInfos.Add(pc.ParameterInfoString);
          }
          sb.Append(string.Join(", ", parameterInfos.ToArray()));
        }
        return sb.ToString();
      }
    }

    public override string ToString() {
      if (ActualValue != null && ActualValue.Value != null) {
        if (Optimize) {
          return string.Format("{0} (Optimize)", NumberedName);
        } else {
          return string.Format("{0}", NumberedName);
        }
      } else {
        return base.ToString();
      }
    }

    public override List<IOptimizable> GetAllOptimizables() {
      var list = new List<IOptimizable>();
      foreach (var pc in ParameterConfigurations) {
        if (pc.Optimize) {
          if (pc.ValueConfigurations.CheckedItems.Count() > 1) list.Add(pc); // only add if there are more than 1 choices. otherwise it makes no sense to optimize which VC is selected
          list.AddRange(pc.GetAllOptimizables());
        }
      }
      return list;
    }

    public override void CollectOptimizedParameterNames(List<string> parameterNames, string prefix) {
      foreach (var pc in ParameterConfigurations) {
        if (pc.Optimize) {
          parameterNames.Add(prefix + pc.ParameterName);
          pc.CollectOptimizedParameterNames(parameterNames, prefix + pc.ParameterName + ".");
        }
      }
    }

    public virtual IEnumerable<string> GetOptimizedParameterNames() {
      var list = new List<string>();
      this.CollectOptimizedParameterNames(list, string.Empty);
      return list;
    }

    public virtual void Parameterize(IParameterizedItem item) {
      foreach (IParameterConfiguration pc in this.ParameterConfigurations) {
        pc.Parameterize((IValueParameter)item.Parameters[pc.ParameterName]);
      }
    }

    public override void Randomize(IRandom random) {
      foreach (IParameterConfiguration pc in this.ParameterConfigurations) {
        pc.Randomize(random);
      }
    }

    public override void Mutate(IRandom random, MutateDelegate mutate, IIntValueManipulator intValueManipulator, IDoubleValueManipulator doubleValueManipulator) {
      foreach (IParameterConfiguration pc in this.ParameterConfigurations) {
        pc.Mutate(random, mutate, intValueManipulator, doubleValueManipulator);
      }
    }

    public override void Cross(IRandom random, IOptimizable other, CrossDelegate cross, IIntValueCrossover intValueCrossover, IDoubleValueCrossover doubleValueCrossover) {
      var otherVc = (ParameterizedValueConfiguration)other;
      for (int i = 0; i < this.ParameterConfigurations.Count; i++) {
        this.ParameterConfigurations.ElementAt(i).Cross(random, otherVc.ParameterConfigurations.ElementAt(i), cross, intValueCrossover, doubleValueCrossover);
      }
    }

    public override double CalculateSimilarity(IOptimizable optimizable) {
      var other = (ParameterizedValueConfiguration)optimizable;
      double sum = 0;
      int count = 0;
      for (int i = 0; i < ParameterConfigurations.Count; i++) {
        if (this.ParameterConfigurations.ElementAt(i).Optimize) {
          sum += this.ParameterConfigurations.ElementAt(i).CalculateSimilarity(other.ParameterConfigurations.ElementAt(i));
          count++;
        }
      }
      return count == 0 ? 1.0 : sum / (double)count;
    }
  }
}