using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Common;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Encodings.BinaryVectorEncoding;
using HeuristicLab.Parameters;
using HeuristicLab.PluginInfrastructure;

namespace HeuristicLab.Problems.NK {

  [Item("IncreasingBlockSizeInteractionsInitializer", "Randomly assignes interactions across all bits but makes sure that different numbers of ineractions are applied to different bits.")]
  [StorableClass]
  public class IncreasingBlockSizeInteractionsInitializer : ParameterizedNamedItem, IInteractionInitializer {    
    
    [StorableConstructor]
    protected IncreasingBlockSizeInteractionsInitializer(bool serializing) : base(serializing) { }
    protected IncreasingBlockSizeInteractionsInitializer(IncreasingBlockSizeInteractionsInitializer original, Cloner cloner) : base(original, cloner) { }
    public IncreasingBlockSizeInteractionsInitializer() {      
    }
    

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

    #region IInteractionInitializer Members
    public BoolMatrix InitializeInterations(int length, int nComponents, int nInteractions, IRandom random) {
      Dictionary<int, int> bitInteractionCounts = new Dictionary<int, int>();
      for (int i = 0; i<length; i++) {
        int count = nInteractions*2*i/length;
        if (count > 0)
          bitInteractionCounts[i] = count;
      }
      List<BinaryVector> components = new List<BinaryVector>();
      while (bitInteractionCounts.Count > 0) {
        BinaryVector component = new BinaryVector(length);
        for (int i = 0; i<nInteractions; i++) {          
          while (bitInteractionCounts.Count > 0) {
            int bit = bitInteractionCounts.ElementAt(random.Next(bitInteractionCounts.Count)).Key;
            if (bitInteractionCounts[bit]-- <= 0)
              bitInteractionCounts.Remove(bit);
            if (!component[bit]) {
              component[bit] = true;
              break;
            }
          }          
        }
        components.Add(component);
      }      
      BoolMatrix m = new BoolMatrix(length, components.Count);
      foreach (var c in components.Select((v, j) => new {v, j})) {
        for (int i = 0; i<c.v.Length; i++) {
          m[i, c.j] = c.v[i];
        }    
      }
      return m;
    }
    #endregion
  }
}