TreeConfiguration - configuration made as simple as it gets (or sets)

// <copyright file="ConfigurationPath.cs" company="MetaPropeller" author="Vladimir Klisic">
//
// Copyright 2005 Vladimir Klisic
// mailto:vladimir.klisic@free.fr
//
// This software is provided 'as-is', without any express or implied
// warranty.  In no event will the authors be held liable for any 
// damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose, 
// including commercial applications, and to alter it and redistribute 
// it freely, subject to the following restrictions: 
//
//  1. The origin of this software must not be misrepresented; you must 
//     not claim that you wrote the original software. If you use this 
//     software in a product, an acknowledgment in the product documentation 
//     would be appreciated but is not required. 
//  2. Altered source versions must be plainly marked as such, and must 
//     not be misrepresented as being the original software. 
//  3. This notice may not be removed or altered from any source distribution. 
//
// </copyright>
//
// <history>
//  <change who=�Vladimir Klisic� date=�2005.02.16�>Initial version</change>
// <history>

using System;
using System.Text;

namespace MetaPropeller.Configuration
{
  /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="T:ConfigurationPath"]/*'/>
  public class ConfigurationPath
  {
    #region Class members
    private string[] _path = null;
    private int _currentSegmentIdx = -1;
    private char[] _separators = { '/', '.', '\\' };
    #endregion

    #region Constructors
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:ConfigurationPath"]/*'/>
    internal ConfigurationPath(string path)
    {
      SetPath(path);
    }
    #endregion

    #region Properties
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="P:Separators"]/*'/>
    public char[] Separators
    {
      get { return _separators; }
      set { _separators = value; }
    }

    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="P:FirstSegment"]/*'/>
    public string FirstSegment
    {
      get 
      { 
        if (_path.Length > 0) 
          return _path[0]; 
        else 
          throw new InvalidOperationException("No path set"); 
      }
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="P:CurrentSegment"]/*'/>
    public string CurrentSegment
    {
      get
      {
        if (_currentSegmentIdx != -1 && _currentSegmentIdx < _path.Length)
          return _path[_currentSegmentIdx];
        else 
          throw new InvalidOperationException("No path set"); 
      }
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="P:LastSegment"]/*'/>
    public string LastSegment
    {
      get
      {
        if (_path.Length > 0)
          return _path[_path.Length-1];
        else 
          throw new InvalidOperationException("No path set"); 
      }
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="P:Length"]/*'/>
    public uint Length
    {
      get  { return _path != null? ((uint) _path.Length) : 0; }
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="P:EndOfPath"]/*'/>
    public bool EndOfPath
    {
      get { return _currentSegmentIdx == -1 || _path == null || _currentSegmentIdx >= _path.Length; }
    }
    #endregion

    #region Methods
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:SetPath"]/*'/>
    public void SetPath(string path)
    {
      string s = path.TrimStart(_separators);
      string[] segments = s.Split(_separators);
      if (segments.Length > 0)
      {
        _path = segments;
        _currentSegmentIdx = _path.Length > 0? 0 : - 1;
      }
      else
        _currentSegmentIdx = -1;
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:MoveToFirstSegment"]/*'/>
    public void MoveToFirstSegment() 
    { 
      if (_path.Length > 0)
        _currentSegmentIdx = 0; 
      else 
        throw new InvalidOperationException("No path set"); 
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:MoveToPrevSegment"]/*'/>
    public void MoveToPrevSegment() 
    { 
      if (_currentSegmentIdx > 0) 
        _currentSegmentIdx--; 
      else 
        throw new InvalidOperationException("No path set"); 
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:MoveToNextSegment"]/*'/>
    public void MoveToNextSegment() 
    { 
      if (_currentSegmentIdx < _path.Length) 
        _currentSegmentIdx++; 
      else 
        throw new InvalidOperationException("No path set"); 
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:MoveToLastSegment"]/*'/>
    public void MoveToLastSegment() 
    { 
      if (_path != null && _path.Length > 0)
        _currentSegmentIdx = _path.Length - 1; 
      else 
        throw new InvalidOperationException("No path set"); 
    }
    /// <include file='docs/ConfigurationPathDoc.xml' path='doc/members/member[@name="M:GetCurrentSegmentParentPath"]/*'/>
    public string GetCurrentSegmentParentPath()
    {
      if (_path == null || _path.Length == 0 || _currentSegmentIdx == -1)
        return String.Empty;
      // All parent nodes that lead to this one: "/root/parent1/parent2"
      string separator = _separators.Length > 0? _separators[0].ToString() : "/";
      StringBuilder sb = new StringBuilder(separator);

      for (int i = 0; i < _currentSegmentIdx; i++)
      {
        sb.Append(_path[i]);
        if (_currentSegmentIdx > i + 1)
          sb.Append(separator);
      }
      return sb.ToString();
    }
    #endregion
  }
}