/******************************************************************/
/* KPresenter - (c) by Reginald Stadlbauer 1997-1998              */
/* Version: 0.1.0                                                 */
/* Author: Reginald Stadlbauer                                    */
/* E-Mail: reggie@kde.org                                         */
/* Homepage: http://boch35.kfunigraz.ac.at/~rs                    */
/* needs c++ library Qt (http://www.troll.no)                     */
/* needs mico (http://diamant.vsb.cs.uni-frankfurt.de/~mico/)     */
/* needs OpenParts and Kom (weis@kde.org)                         */
/* written for KDE (http://www.kde.org)                           */
/* License: GNU GPL                                               */
/******************************************************************/
/* Module: Command History                                        */
/******************************************************************/

#include "commandhistory.h"
#include "commandhistory.moc"

/******************************************************************/
/* Class: CommandHistory                                          */
/******************************************************************/

/*====================== constructor =============================*/
CommandHistory::CommandHistory()
{
  commands.setAutoDelete(true);
  present = 0;
}

/*======================= destructor =============================*/
CommandHistory::~CommandHistory()
{
  commands.clear();
}

/*====================== add command =============================*/
void CommandHistory::addCommand(Command *_command)
{
  if (present < static_cast<int>(commands.count()))
    {
      QList<Command> _commands;
      _commands.setAutoDelete(false);
  
      for (int i = 0;i < present;i++)
	{    
	  _commands.insert(i,commands.at(0));
	  commands.take(0);
	}
      
      _commands.append(_command);
      commands.clear();
      commands = _commands;
      commands.setAutoDelete(true);
    }
  else
    commands.append(_command);

  if (commands.count() > MAX_UNDO_REDO)
    commands.removeFirst();
  else
    present++;

  emit undoRedoChanged(getUndoName(),getRedoName());
}

/*======================= undo ===================================*/
void CommandHistory::undo()
{
  if (present > 0)
    {
      commands.at(present - 1)->unexecute();
      present--;
      emit undoRedoChanged(getUndoName(),getRedoName());
    }
}

/*======================= redo ===================================*/
void CommandHistory::redo()
{
  if (present < static_cast<int>(commands.count()))
    {
      commands.at(present)->execute();
      present++;
      emit undoRedoChanged(getUndoName(),getRedoName());
    }
}

/*======================== get undo name ========================*/
QString CommandHistory::getUndoName()
{
  if (present > 0)
    return commands.at(present - 1)->getName();
  else
    return QString();
}

/*======================== get redo name ========================*/
QString CommandHistory::getRedoName()
{
  if (present < static_cast<int>(commands.count()))
    return commands.at(present)->getName();
  else
    return QString();
}