using System.Collections.Generic;
using System.Linq;
using HeuristicLab.Collections;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HEAL.Attic;

namespace HeuristicLab.Problems.MetaOptimization {
  // todo: check that at least 1 elements needs to be selected
  // todo: control creatable item types
  [StorableType("D6F285A9-E8F7-4136-A685-B2EBEA53FEA0")]
  public class CheckedValueConfigurationList : CheckedItemList<IValueConfiguration>, ICheckedValueConfigurationList {
    [Storable]
    private int minItemCount = 1;
    public int MinItemCount {
      get { return minItemCount; }
    }

    [Storable]
    protected IItemSet<IItem> validValues;
    public IItemSet<IItem> ValidValues {
      get { return validValues; }
    }

    public CheckedValueConfigurationList(IItemSet<IItem> validValues) {
      this.validValues = validValues;
      RegisterEvents();
    }
    public CheckedValueConfigurationList(IEnumerable<IValueConfiguration> collection)
      : base(collection) {
      validValues = null;
      // event wiring not needed
    }
    public CheckedValueConfigurationList() {
      RegisterEvents();
    }
    [StorableConstructor]
    protected CheckedValueConfigurationList(StorableConstructorFlag _) : base(_) {
      RegisterEvents();
    }
    protected CheckedValueConfigurationList(CheckedValueConfigurationList original, Cloner cloner)
      : base(original, cloner) {
      this.minItemCount = original.MinItemCount;
      this.validValues = cloner.Clone(original.validValues);
      RegisterEvents();
    }

    public override IDeepCloneable Clone(Cloner cloner) {
      return new CheckedValueConfigurationList(this, cloner);
    }
    [StorableHook(HookType.AfterDeserialization)]
    private void AfterDeserialization() {
      RegisterEvents();
    }

    private void RegisterEvents() {
      this.ItemsAdded += new CollectionItemsChangedEventHandler<IndexedItem<IValueConfiguration>>(CheckedValueConfigurationList_ItemsAdded);
      this.ItemsRemoved += new CollectionItemsChangedEventHandler<IndexedItem<IValueConfiguration>>(CheckedValueConfigurationList_ItemsRemoved);
    }

    private void DeregisterEvents() {
      this.ItemsRemoved -= new CollectionItemsChangedEventHandler<IndexedItem<IValueConfiguration>>(CheckedValueConfigurationList_ItemsRemoved);
      this.ItemsAdded -= new CollectionItemsChangedEventHandler<IndexedItem<IValueConfiguration>>(CheckedValueConfigurationList_ItemsAdded);
    }

    private void CheckedValueConfigurationList_ItemsAdded(object sender, CollectionItemsChangedEventArgs<IndexedItem<IValueConfiguration>> e) {
      foreach (var item in e.Items) {
        var matchingItems = this.Where(x => x != item.Value && x.ActualValue.ValueDataType == item.Value.ActualValue.ValueDataType);
        if (matchingItems.Count() > 0) {
          int maxNumber = matchingItems.Select(x => x.Number).Max();
          item.Value.Number = maxNumber + 1;
        }
      }
    }

    private void CheckedValueConfigurationList_ItemsRemoved(object sender, CollectionItemsChangedEventArgs<IndexedItem<IValueConfiguration>> e) {
      // auch collectionreset gehört berücksichtigt
      // funktioniert so nicht ganz, weil die view das hinzufügen nicht mitkriegt
      //if (this.Count < minItemCount) {
      //  foreach (var item in e.Items) {
      //    if (this.Count >= minItemCount)
      //      break;
      //    this.Add(item);
      //  }
      //}
    }

  }
}