/*
* SplitCmd.java
*
* Copyright (c) 1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and
* redistribution of this file, and for a DISCLAIMER OF ALL
* WARRANTIES.
* 
* Included in SQLite3 port to C# for use in testharness only;  2008 Noah B Hart
*
* RCS @(#) $Id: SplitCmd.java,v 1.1.1.1 1998/10/14 21:09:19 cvsadmin Exp $
*
*/
using System;
namespace tcl.lang
{

  /// <summary> This class implements the built-in "split" command in Tcl.</summary>

  class SplitCmd : Command
  {
    /// <summary> Default characters for splitting up strings.</summary>

    private static char[] defSplitChars = new char[] { ' ', '\n', '\t', '\r' };

    /// <summary> This procedure is invoked to process the "split" Tcl
    /// command. See Tcl user documentation for details.
    /// 
    /// </summary>
    /// <param name="interp">the current interpreter.
    /// </param>
    /// <param name="argv">command arguments.
    /// </param>
    /// <exception cref=""> TclException If incorrect number of arguments.
    /// </exception>

    public TCL.CompletionCode cmdProc( Interp interp, TclObject[] argv )
    {
      char[] splitChars = null;
      string inString;

      if ( argv.Length == 2 )
      {
        splitChars = defSplitChars;
      }
      else if ( argv.Length == 3 )
      {

        splitChars = argv[2].ToString().ToCharArray();
      }
      else
      {
        throw new TclNumArgsException( interp, 1, argv, "string ?splitChars?" );
      }


      inString = argv[1].ToString();
      int len = inString.Length;
      int num = splitChars.Length;

      /*
      * Handle the special case of splitting on every character.
      */

      if ( num == 0 )
      {
        TclObject list = TclList.newInstance();

        list.preserve();
        try
        {
          for ( int i = 0; i < len; i++ )
          {
            TclList.append( interp, list, TclString.newInstance( inString[i] ) );
          }
          interp.setResult( list );
        }
        finally
        {
          list.release();
        }
        return TCL.CompletionCode.RETURN;
      }

      /*
      * Normal case: split on any of a given set of characters.
      * Discard instances of the split characters.
      */
      TclObject list2 = TclList.newInstance();
      int elemStart = 0;

      list2.preserve();
      try
      {
        int i, j;
        for ( i = 0; i < len; i++ )
        {
          char c = inString[i];
          for ( j = 0; j < num; j++ )
          {
            if ( c == splitChars[j] )
            {
              TclList.append( interp, list2, TclString.newInstance( inString.Substring( elemStart, ( i ) - ( elemStart ) ) ) );
              elemStart = i + 1;
              break;
            }
          }
        }
        if ( i != 0 )
        {
          TclList.append( interp, list2, TclString.newInstance( inString.Substring( elemStart ) ) );
        }
        interp.setResult( list2 );
      }
      finally
      {
        list2.release();
      }
      return TCL.CompletionCode.RETURN;
    }
  }
}