#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2010 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.Text;
using HeuristicLab.Core;
using HeuristicLab.Common;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Symbols;
using HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols;

namespace HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Formatters {

  [Item("SymbolicExpressionTreeSmalltalkStringFormatter", "String formatter for string representations of symbolic expression trees in Smalltalk syntax.")]
  [StorableClass]
  public class SymbolicExpressionTreeSmalltalkStringFormatter : NamedItem, ISymbolicExpressionTreeStringFormatter {

    [StorableConstructor]
    protected SymbolicExpressionTreeSmalltalkStringFormatter(bool deserializing) : base(deserializing) { }
    protected SymbolicExpressionTreeSmalltalkStringFormatter(SymbolicExpressionTreeSmalltalkStringFormatter original, Cloner cloner) : base(original, cloner) { }
    public SymbolicExpressionTreeSmalltalkStringFormatter()
        : base() {
      Name = "Smalltalk String Formatter";
    }

    public string Format(SymbolicExpressionTree symbolicExpressionTree) {
      return FormatRecursively(symbolicExpressionTree.Root);
    }

    private string FormatRecursively(SymbolicExpressionTreeNode node) {
      StringBuilder stringBuilder = new StringBuilder();

      Symbol symbol = node.Symbol;
      if (symbol is Addition) {
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("+");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
      } else if (symbol is And) {
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("&");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
      } else if (symbol is Average) {
        stringBuilder.Append("(1/");
        stringBuilder.Append(node.SubTrees.Count);
        stringBuilder.Append(")*(");
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("+");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
        stringBuilder.Append(")");
      } else if (symbol is Constant) {
        ConstantTreeNode constantTreeNode = node as ConstantTreeNode;
        stringBuilder.Append(constantTreeNode.Value);
      } else if (symbol is Cosine) {
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append("cos");
      } else if (symbol is Division) {
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("/");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
      } else if (symbol is Exponential) {
        stringBuilder.Append("not yet implemented");
      } else if (symbol is GreaterThan) {
        stringBuilder.Append("(");
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append(">");
        stringBuilder.Append(FormatRecursively(node.SubTrees[1]));
        stringBuilder.Append(")");
      } else if (symbol is IfThenElse) {
        stringBuilder.Append("(");
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append(" ifTrue: [");
        stringBuilder.Append(FormatRecursively(node.SubTrees[1]));
        stringBuilder.Append("] ifFalse: [");
        stringBuilder.Append(FormatRecursively(node.SubTrees[2]));
        stringBuilder.Append("] )");
      } else if (symbol is LaggedVariable) {
        stringBuilder.Append("not implemented");
      } else if (symbol is LessThan) {
        stringBuilder.Append("(");
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append("<");
        stringBuilder.Append(FormatRecursively(node.SubTrees[1]));
        stringBuilder.Append(")");
      } else if (symbol is Logarithm) {
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append("log");
      } else if (symbol is Multiplication) {
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("*");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
      } else if (symbol is Not) {
        stringBuilder.Append("!");
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
      } else if (symbol is Or) {
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("|");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
      } else if (symbol is Sine) {
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append("sin");
      } else if (symbol is Subtraction) {
        for (int i = 0; i < node.SubTrees.Count; i++) {
          if (i > 0) stringBuilder.Append("-");
          stringBuilder.Append("(");
          stringBuilder.Append(FormatRecursively(node.SubTrees[i]));
          stringBuilder.Append(")");
        }
      } else if (symbol is Tangent) {
        stringBuilder.Append(FormatRecursively(node.SubTrees[0]));
        stringBuilder.Append("tan");
      } else if (symbol is HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols.Variable) {
        stringBuilder.Append("not yet implemented");
      }

      else {
        stringBuilder.Append("ERROR");
      }

      return stringBuilder.ToString();
    }

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

  }

}