#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2016 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.Linq;
using System.Text;
using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;

namespace HeuristicLab.Problems.DataAnalysis.Symbolic {
  public static class SchemaUtil {
    private static readonly Dictionary<string, string> ShortNames = new Dictionary<string, string> {
      { "Addition", "+" },
      { "Subtraction", "-" },
      { "Multiplication", "*" },
      { "Division", "/" },
      { "Logarithm", "Log" },
      { "Exponential", "Exp" }
    };

    public static void ReplaceSubtree(ISymbolicExpressionTreeNode original, ISymbolicExpressionTreeNode replacement, bool preserveChildren = true) {
      var parent = original.Parent;
      if (parent == null)
        throw new ArgumentException("Parent cannot be null for node " + original);
      var index = parent.IndexOfSubtree(original);
      parent.RemoveSubtree(index);
      parent.InsertSubtree(index, replacement);

      if (preserveChildren) {
        var subtrees = original.Subtrees.ToList();

        for (int i = subtrees.Count - 1; i >= 0; --i)
          original.RemoveSubtree(i);

        for (int i = 0; i < subtrees.Count; ++i) {
          replacement.AddSubtree(subtrees[i]);
        }
      }
    }

    public static string FormatToString(this ISymbolicExpressionTreeNode node, bool strict = false) {
      StringBuilder strBuilder = new StringBuilder();
      // internal nodes or leaf nodes?
      if (node is AnySubtree)
        return "# ";

      if (node.SubtreeCount > 0) {
        strBuilder.Append("(");
        // symbol on same line as '('
        string label = string.Empty;
        if (node is AnyNode)
          label = "=";
        else {
          string shortName;
          ShortNames.TryGetValue(node.Symbol.Name, out shortName);
          label = string.IsNullOrEmpty(shortName) ? node.Symbol.Name : shortName;
        }
        strBuilder.Append(label + " ");
        // each subtree expression on a new line
        // and closing ')' also on new line
        foreach (var subtree in node.Subtrees) {
          strBuilder.Append(subtree.FormatToString(strict));
        }
        strBuilder.Append(") ");
      } else {
        // symbol in the same line with as '(' and ')'
        var v = node as VariableTreeNode;
        var c = node as ConstantTreeNode;
        var w = node as AnyNode; // wildcard
        string label = string.Empty;
        if (w != null)
          label = "=";
        else if (v != null)
          label = strict ? string.Format("{0:0.00}_{1}", v.Weight, v.VariableName) : string.Format("{0}", v.VariableName);
        else if (c != null)
          label = strict ? string.Format("{0:0.00}", c.Value) : "C";
        strBuilder.Append(label);
        if (node.Parent != null && node != node.Parent.Subtrees.Last())
          strBuilder.Append(" ");
        //strBuilder.Append(")");
      }
      return strBuilder.ToString();
    }
  }
}