#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.Linq;
using HeuristicLab.Persistence.Data;

namespace HeuristicLab.Persistence {
  internal abstract class GenericArrayTransformer<TSource, TTarget> : TransformerBase {
    public override bool CanTransformType(Type type) {
      return type.IsArray && (type.GetElementType() == typeof(TSource));
    }

    public override PersistenceData ToData(object o, PersistenceMapper mapper) {
      var arr = (Array)o;
      var data = new ArrayData<TTarget>(Id);
      mapper.Cache(o, data);
      var elementType = arr.GetType().GetElementType();
      data.ElementTypeId = mapper.GetTypeId(elementType);

      if (arr.Rank == 1) {
        data.Values = GetTargets((TSource[])o, mapper);
        //data.Values = GetTargets(Array.ConvertAll(arr, x => (object)x), mapper);
        //data.Values = GetTargets(arr.Cast<TSource>().ToArray(), mapper);
        return data;
      } else {
        data.Lengths = new int[arr.Rank];
        int[] positions = new int[arr.Rank];
        for (int i = 0; i < arr.Rank; i++) {
          data.Lengths[i] = arr.GetLength(i);
          positions[i] = 0;
        }

        data.Values = new TTarget[arr.Length];
        for (int i = 0; i < data.Values.Length; i++) {
          data.Values[i] = GetTarget((TSource)arr.GetValue(positions), mapper);
          positions[0] += 1;
          for (int j = 0; j < arr.Rank - 1; j++) {
            if (positions[j] >= data.Lengths[j]) {
              positions[j] = 0;
              positions[j + 1] += 1;
            } else {
              break;
            }
          }
        }
        return data;
      }
    }

    public override object ToObject(PersistenceData data, PersistenceMapper mapper) {
      var arrayData = (ArrayData<TTarget>)data;
      var elementType = mapper.GetType(arrayData.ElementTypeId);
      if (arrayData.Lengths.Length <= 1) {  // single dimensional
        var o = GetSources(arrayData.Values, mapper);
        mapper.Cache(data, o);
        return o;
      } else {
        var o = Array.CreateInstance(elementType, arrayData.Lengths);
        mapper.Cache(data, o);

        int[] positions = new int[arrayData.Lengths.Length];
        positions.Initialize();
        for (int i = 0; i < arrayData.Values.Length; i++) {
          o.SetValue(GetSource(arrayData.Values[i], mapper), positions);
          positions[0] += 1;
          for (int j = 0; j < o.Rank - 1; j++) {
            if (positions[j] >= arrayData.Lengths[j]) {
              positions[j] = 0;
              positions[j + 1] += 1;
            } else {
              break;
            }
          }
        }
        return o;
      }
    }

    protected abstract TTarget[] GetTargets(TSource[] sources, PersistenceMapper mapper);
    protected abstract TSource[] GetSources(TTarget[] targets, PersistenceMapper mapper);
    protected abstract TTarget GetTarget(TSource source, PersistenceMapper mapper);
    protected abstract TSource GetSource(TTarget target, PersistenceMapper mapper);
  }

  internal abstract class PrimitiveArrayTransformer<T> : GenericArrayTransformer<T, T> {
    protected override T[] GetTargets(T[] sources, PersistenceMapper mapper) {
      return sources;
    }
    protected override T[] GetSources(T[] targets, PersistenceMapper mapper) {
      return targets;
    }
    protected override T GetTarget(T source, PersistenceMapper mapper) {
      return source;
    }
    protected override T GetSource(T target, PersistenceMapper mapper) {
      return target;
    }
  }

  [Transformer("F25A73B2-6B67-4493-BD59-B836AF4455D1", 300)]
  internal sealed class BoolArrayTransformer : PrimitiveArrayTransformer<bool> { }

  [Transformer("FF89F6D1-CDE3-498E-9166-F70AC6EB01F1", 301)]
  internal sealed class ByteArrayTransformer : PrimitiveArrayTransformer<byte> { }

  [Transformer("B49B3F2D-2E97-4BAB-8705-8D29DA707C6A", 302)]
  internal sealed class SByteArrayTransformer : PrimitiveArrayTransformer<sbyte> { }

  [Transformer("2811FDD4-6800-4CBA-86D7-9071ED5775ED", 303)]
  internal sealed class ShortArrayTransformer : PrimitiveArrayTransformer<short> { }

  [Transformer("1AAC2625-356C-40BC-8CB4-15CB3D047EB8", 304)]
  internal sealed class UShortArrayTransformer : PrimitiveArrayTransformer<ushort> { }

  [Transformer("12F19098-5D49-4C23-8897-69087F1C146D", 305)]
  internal sealed class CharArrayTransformer : PrimitiveArrayTransformer<char> { }

  [Transformer("5F6DC3BC-4433-4AE9-A636-4BD126F7DACD", 306)]
  internal sealed class IntArrayTransformer : PrimitiveArrayTransformer<int> { }

  [Transformer("3F10274F-D350-4C82-89EA-A5EB36D4EFCC", 307)]
  internal sealed class UIntArrayTransformer : PrimitiveArrayTransformer<uint> { }

  [Transformer("E9D550E2-57F7-47F3-803D-37A619DA1A5C", 308)]
  internal sealed class LongArrayTransformer : PrimitiveArrayTransformer<long> { }

  [Transformer("C02A205B-2176-4282-AC2B-ADEF96DDBE24", 309)]
  internal sealed class ULongArrayTransformer : PrimitiveArrayTransformer<ulong> { }

  [Transformer("3C4590D9-C76E-4AFB-98FD-E50D3D051648", 310)]
  internal sealed class FloatArrayTransformer : PrimitiveArrayTransformer<float> { }

  [Transformer("FB98C399-9323-4470-9A85-9186C2B2D5D4", 311)]
  internal sealed class DoubleArrayTransformer : PrimitiveArrayTransformer<double> { }

  [Transformer("9E68A52B-2EC8-447E-B45B-D382A16283D4", 312)]
  internal sealed class DecimalArrayTransformer : PrimitiveArrayTransformer<decimal> { }

  [Transformer("68332513-9CF1-47FA-A093-6DDB663186EC", 313)]
  internal sealed class StringArrayTransformer : PrimitiveArrayTransformer<string> { }

  [Transformer("C83F0B5A-68D8-4271-81F9-FF259FC6F126", 400)]
  internal sealed class ArrayTransformer : GenericArrayTransformer<object, uint> {
    public override bool CanTransformType(Type type) {
      return type.IsArray;
    }

    protected override uint[] GetTargets(object[] sources, PersistenceMapper mapper) {
      return sources.Select(x => mapper.GetDataId(x)).ToArray();
    }
    protected override object[] GetSources(uint[] targets, PersistenceMapper mapper) {
      return targets.Select(x => mapper.GetObject(x)).ToArray();
    }
    protected override uint GetTarget(object source, PersistenceMapper mapper) {
      return mapper.GetDataId(source);
    }
    protected override object GetSource(uint target, PersistenceMapper mapper) {
      return mapper.GetObject(target);
    }
  }
}