source: branches/PersistenceOverhaul/HeuristicLab.Persistence/4.0/Transformers/DictionaryTransformer.cs @ 16612

#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2012 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;
using System.Collections.Generic;
using HeuristicLab.Persistence.Data;

namespace HeuristicLab.Persistence {
  internal abstract class GenericDictionaryTransformer : TransformerBase {
    public override bool CanTransformType(Type type) {
      return type.IsGenericType && (type.GetGenericTypeDefinition() == typeof(Dictionary<,>));
    }
    public override PersistenceData ToData(object o, PersistenceMapper mapper) {
      var type = o.GetType();
      var data = new DictionaryData(Id);
      mapper.Cache(o, data);
      data.TypeId = mapper.GetTypeId(type);

      var dict = (IDictionary)o;
      data.KeyIds = new uint[dict.Count];
      data.ValueIds = new uint[dict.Count];
      int i = 0;
      foreach (DictionaryEntry element in dict) {
        data.KeyIds[i] = GetTargetKey(element.Key, mapper);
        data.ValueIds[i] = GetTargetValue(element.Value, mapper);
        i++;
      }
      data.ComparerId = mapper.GetDataId(type.GetProperty("Comparer").GetValue(o, null));
      return data;
    }

    public override object ToObject(PersistenceData data, PersistenceMapper mapper) {
      var composite = (DictionaryData)data;
      var type = mapper.GetType(composite.TypeId);
      var o = (IDictionary)Activator.CreateInstance(type, mapper.GetObject(composite.ComparerId));
      mapper.Cache(data, o);
      for (int i = 0; i < composite.KeyIds.Length; i++) {
        o.Add(GetSourceKey(composite.KeyIds[i], mapper), GetSourceValue(composite.ValueIds[i], mapper));
      }
      return o;
    }

    protected abstract uint GetTargetKey(object sourceKey, PersistenceMapper mapper);
    protected abstract uint GetTargetValue(object sourceValue, PersistenceMapper mapper);
    protected abstract object GetSourceKey(uint targetKey, PersistenceMapper mapper);
    protected abstract object GetSourceValue(uint targetValue, PersistenceMapper mapper);
  }

  [Transformer("AC7F11D4-3390-4DE2-B6FC-1705DAB627F6", 403)]
  internal sealed class StringDictionaryTransformer : GenericDictionaryTransformer {
    public override bool CanTransformType(Type type) {
      return base.CanTransformType(type) && (type.GetGenericArguments()[0] == typeof(string));
    }
    protected override uint GetTargetKey(object sourceKey, PersistenceMapper mapper) {
      return mapper.GetStringId((string)sourceKey);
    }
    protected override uint GetTargetValue(object sourceValue, PersistenceMapper mapper) {
      return mapper.GetDataId(sourceValue);
    }
    protected override object GetSourceKey(uint targetKey, PersistenceMapper mapper) {
      return mapper.GetString(targetKey);
    }
    protected override object GetSourceValue(uint targetValue, PersistenceMapper mapper) {
      return mapper.GetObject(targetValue);
    }
  }

  [Transformer("D1EF55D6-843A-42AF-8EBB-49566981C943", 404)]
  internal sealed class DictionaryTransformer : GenericDictionaryTransformer {
    protected override uint GetTargetKey(object sourceKey, PersistenceMapper mapper) {
      return mapper.GetDataId(sourceKey);
    }
    protected override uint GetTargetValue(object sourceValue, PersistenceMapper mapper) {
      return mapper.GetDataId(sourceValue);
    }
    protected override object GetSourceKey(uint targetKey, PersistenceMapper mapper) {
      return mapper.GetObject(targetKey);
    }
    protected override object GetSourceValue(uint targetValue, PersistenceMapper mapper) {
      return mapper.GetObject(targetValue);
    }
  }
}