#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2014 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

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

namespace HeuristicLab.Problems.ProgramSynthesis {
  [StorableClass]
  [Item("GenealogyGraph", "A class representing a genealogy graph")]
  public class GenealogyGraph : DirectedGraph, IGenealogyGraph {
    private Dictionary<object, IGenealogyGraphNode> contentMap;
    private Dictionary<string, IGenealogyGraphNode> idMap;

    private readonly Comparison<IArc<IDeepCloneable>> compareArcs = (a, b) => {
      var da = a.Data;
      var db = b.Data;

      if ((da == null && db == null) || (da != null && db != null))
        return 0;

      if (da == null)
        return -1;

      return 1;
    };

    protected Dictionary<double, List<IGenealogyGraphNode>> ranks;
    public IEnumerable<KeyValuePair<double, IEnumerable<IGenealogyGraphNode>>> Ranks {
      get { return ranks.Select(x => new KeyValuePair<double, IEnumerable<IGenealogyGraphNode>>(x.Key, x.Value)); }
    }
    public IEnumerable<IGenealogyGraphNode> GetByRank(double rank) {
      return ranks.ContainsKey(rank) ? ranks[rank] : Enumerable.Empty<IGenealogyGraphNode>();
    }
    protected GenealogyGraph(GenealogyGraph original, Cloner cloner)
      : base(original, cloner) {
      RebuildDictionaries();
      // sort arcs so that in the case of crossover (child vertex with two parents)
      // the arc which holds the fragment information is always last
      foreach (var arcList in base.Vertices.Select(v => (List<IArc>)v.InArcs)) {
        arcList.Sort((a, b) => compareArcs((IGenealogyGraphArc)a, (IGenealogyGraphArc)b));
      }
    }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new GenealogyGraph(this, cloner);
    }

    [StorableConstructor]
    protected GenealogyGraph(bool deserializing)
      : base(deserializing) {
    }
    [StorableHook(HookType.AfterDeserialization)]
    private void AfterDeserialization() {
      RebuildDictionaries();
      foreach (var arcList in base.Vertices.Select(v => (List<IArc>)v.InArcs)) {
        arcList.Sort((a, b) => compareArcs((IGenealogyGraphArc)a, (IGenealogyGraphArc)b));
      }
    }
    public GenealogyGraph() {
      ranks = new Dictionary<double, List<IGenealogyGraphNode>>();
      contentMap = new Dictionary<object, IGenealogyGraphNode>();
      idMap = new Dictionary<string, IGenealogyGraphNode>();
    }
    new public IEnumerable<IGenealogyGraphNode> Vertices {
      get { return base.Vertices.Select(x => (IGenealogyGraphNode)x); }
    }
    new public IEnumerable<IGenealogyGraphArc> Arcs {
      get { return base.Arcs.Select(x => (IGenealogyGraphArc)x); }
    }
    public override IArc AddArc(IVertex source, IVertex target) {
      var arc = new GenealogyGraphArc((IGenealogyGraphNode)source, (IGenealogyGraphNode)target);
      base.AddArc(arc);
      return arc;
    }
    public override void AddVertex(IVertex vertex) {
      base.AddVertex(vertex);
      var genealogyGraphNode = (IGenealogyGraphNode)vertex;

      if (contentMap.ContainsKey(genealogyGraphNode.Data))
        throw new InvalidOperationException("Duplicate content is not allowed in the genealogy graph.");
      contentMap[genealogyGraphNode.Data] = genealogyGraphNode;

      if (idMap.ContainsKey(genealogyGraphNode.Id))
        throw new InvalidOperationException("Duplicate ids are not allowed in the genealogy graph.");
      idMap[genealogyGraphNode.Id] = genealogyGraphNode;

      if (!ranks.ContainsKey(genealogyGraphNode.Rank))
        ranks[genealogyGraphNode.Rank] = new List<IGenealogyGraphNode>();
      ranks[genealogyGraphNode.Rank].Add(genealogyGraphNode);
    }
    public override void RemoveVertex(IVertex vertex) {
      var node = (IGenealogyGraphNode)vertex;
      contentMap.Remove(node.Data);
      idMap.Remove(node.Id);
      if (ranks.ContainsKey(node.Rank)) {
        ranks[node.Rank].Remove(node); // this call will be slow, use with caution
        if (!ranks[node.Rank].Any())
          ranks.Remove(node.Rank);
      }
      base.RemoveVertex(vertex);
    }

    public override void RemoveVertices(IEnumerable<IVertex> vertices) {
      foreach (var v in vertices)
        this.RemoveVertex(v);
    }

    public IGenealogyGraphNode GetByContent(object content) {
      IGenealogyGraphNode result;
      contentMap.TryGetValue(content, out result);
      return result;
    }
    public IGenealogyGraphNode GetById(string id) {
      IGenealogyGraphNode result;
      idMap.TryGetValue(id, out result);
      return result;
    }
    public bool Contains(object content) {
      return contentMap.ContainsKey(content);
    }
    public event EventHandler GraphUpdated;
    private void OnGraphUpdated(object sender, EventArgs args) {
      var updated = GraphUpdated;
      if (updated != null) updated(sender, args);
    }
    public override void Clear() {
      base.Clear();
      ranks.Clear();
      contentMap.Clear();
      idMap.Clear();
    }
    private void RebuildDictionaries() {
      contentMap = new Dictionary<object, IGenealogyGraphNode>();
      idMap = new Dictionary<string, IGenealogyGraphNode>();
      ranks = new Dictionary<double, List<IGenealogyGraphNode>>();

      foreach (var v in Vertices) {
        contentMap[v.Data] = v;
        idMap[v.Id] = v;
        if (ranks.ContainsKey(v.Rank)) {
          ranks[v.Rank].Add(v);
        } else {
          ranks[v.Rank] = new List<IGenealogyGraphNode> { v };
        }
      }
    }
    public void ExportDot(string path) {
      var sb = new StringBuilder();
      sb.AppendLine("graph fragmentgraph {");
      foreach (var v in Vertices) {
        double width = Math.Max(0.5, v.Degree);
        sb.AppendLine("\"" + v.Id + "\"[shape=circle, style = filled, width = " + width + ", label = " + v.Rank + "\n" + String.Format("{0:00}", v.Quality) + ", fillcolor = \"" + ColorTranslator.ToHtml(GetColor(v)) + "\"]");
      }
      foreach (var a in Arcs) {
        sb.AppendLine("\"" + a.Source.Id + "\" -- \"" + a.Target.Id + "\"");
      }

      sb.AppendLine("}");
      File.WriteAllText(path, sb.ToString());
    }
    private Color GetColor(IGenealogyGraphNode node) {
      var colorIndex = (int)Math.Round(node.Quality * ColorGradient.Colors.Count);
      if (colorIndex >= ColorGradient.Colors.Count) return ColorGradient.Colors.Last();
      return ColorGradient.Colors[colorIndex];
    }
  }

  [Item("GenealogyGraph", "A genealogy graph in which the vertex data is of type T")]
  [StorableClass]
  public class GenealogyGraph<T> : GenealogyGraph, IGenealogyGraph<T> where T : class, IItem {
    public GenealogyGraph() { }
    private GenealogyGraph(GenealogyGraph original, Cloner cloner)
      : base(original, cloner) {
    }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new GenealogyGraph<T>(this, cloner);
    }
    new public IEnumerable<IGenealogyGraphNode<T>> Vertices {
      get { return base.Vertices.Select(x => (IGenealogyGraphNode<T>)x); }
    }
    new public IGenealogyGraphNode<T> GetByContent(object content) {
      return (IGenealogyGraphNode<T>)base.GetByContent(content);
    }
    new public IGenealogyGraphNode<T> GetById(string id) {
      return (IGenealogyGraphNode<T>)base.GetById(id);
    }
    new public IEnumerable<IGenealogyGraphNode<T>> GetByRank(double rank) {
      return base.GetByRank(rank).Select(x => (IGenealogyGraphNode<T>)x);
    }
    public new IEnumerable<KeyValuePair<double, IEnumerable<IGenealogyGraphNode<T>>>> Ranks {
      get { return base.Ranks.Select(x => new KeyValuePair<double, IEnumerable<IGenealogyGraphNode<T>>>(x.Key, x.Value.Select(n => (IGenealogyGraphNode<T>)n))); }
    }
  }
}