#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.IO;
using System.Linq;
using System.Text;
using System.Xml;
using ICSharpCode.AvalonEdit.CodeCompletion;
using ICSharpCode.NRefactory.Completion;
using ICSharpCode.NRefactory.CSharp;
using ICSharpCode.NRefactory.TypeSystem;

namespace HeuristicLab.CodeEditor {
  internal class EntityCompletionData : CompletionData, IEntityCompletionData {
    private static readonly CSharpAmbience Ambience = new CSharpAmbience();

    #region IEntityCompletionData Members
    public IEntity Entity { get; private set; }
    #endregion

    public EntityCompletionData(IEntity entity)
      : base() {
      if (entity == null) throw new ArgumentException("entity");

      Entity = entity;
      Ambience.ConversionFlags = entity is ITypeDefinition ? ConversionFlags.ShowTypeParameterList : ConversionFlags.None;
      DisplayText = entity.Name;
      CompletionText = Ambience.ConvertSymbol(entity);
      Image = CompletionImage.GetImage(entity);
    }

    private string description;
    public override string Description {
      get {
        if (string.IsNullOrEmpty(description)) {
          description = GetText(Entity);
          if (HasOverloads)
            description += string.Format(" (+{0} overloads)", OverloadedData.Count());
          description += Environment.NewLine + XmlDocumentationToText(Entity.Documentation);
        }
        return description;
      }
      set { description = value; }
    }

    public static string XmlDocumentationToText(string xmlDoc) {
      System.Diagnostics.Debug.WriteLine(xmlDoc);
      var b = new StringBuilder();
      try {
        using (var reader = new XmlTextReader(new StringReader("<root>" + xmlDoc + "</root>"))) {
          reader.XmlResolver = null;
          while (reader.Read()) {
            switch (reader.NodeType) {
              case XmlNodeType.Text:
                b.Append(reader.Value);
                break;
              case XmlNodeType.Element:
                switch (reader.Name) {
                  case "filterpriority":
                    reader.Skip();
                    break;
                  case "returns":
                    b.AppendLine();
                    b.Append("Returns: ");
                    break;
                  case "param":
                    b.AppendLine();
                    b.Append(reader.GetAttribute("name") + ": ");
                    break;
                  case "remarks":
                    b.AppendLine();
                    b.Append("Remarks: ");
                    break;
                  case "see":
                    if (reader.IsEmptyElement) {
                      b.Append(reader.GetAttribute("cref"));
                    } else {
                      reader.MoveToContent();
                      if (reader.HasValue) {
                        b.Append(reader.Value);
                      } else {
                        b.Append(reader.GetAttribute("cref"));
                      }
                    }
                    break;
                }
                break;
            }
          }
        }
        return b.ToString();
      } catch (XmlException) {
        return xmlDoc;
      }
    }

    #region Helpers
    private static string GetText(IEntity entity) {
      Ambience.ConversionFlags = ConversionFlags.StandardConversionFlags;
      if (entity is ITypeDefinition) Ambience.ConversionFlags |= ConversionFlags.UseFullyQualifiedEntityNames;
      if (entity is IMethod) {
        var reducedForm = ((IMethod)entity).ReducedFrom;
        if (reducedForm != null) entity = reducedForm;
      }
      return Ambience.ConvertSymbol(entity);
    }
    #endregion
  }
}