1 files changed, 119 insertions, 0 deletions
diff --git a/kaddressbook/undo.cpp b/kaddressbook/undo.cpp
new file mode 100644
index 0000000..4442087
--- a/dev/null
+++ b/kaddressbook/undo.cpp
@@ -0,0 +1,119 @@
+/*
+    This file is part of KAddressBook.
+    Copyright (C) 1999 Don Sanders <sanders@kde.org>
+
+    This program 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 2 of the License, or
+    (at your option) any later version.
+
+    This program 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 this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+    As a special exception, permission is given to link this program
+    with any edition of Qt, and distribute the resulting executable,
+    without including the source code for Qt in the source distribution.
+*/
+
+#include "undo.h"
+
+///////////////////////////////
+// StackBase
+
+void StackBase::push(Command *c)
+{
+  mCommandStack.push(c);
+  emit changed();
+}
+
+bool StackBase::isEmpty()
+{
+  return mCommandStack.isEmpty();
+}
+
+Command *StackBase::top()
+{
+  return mCommandStack.top();
+}
+
+void StackBase::clear()
+{
+  mCommandStack.clear();
+  emit changed();
+}
+
+Command *StackBase::pop()
+{
+  Command *c = mCommandStack.pop();
+  if (c)
+    emit changed();
+    
+  return c;
+}
+
+///////////////////////////////
+// UndoStack
+
+UndoStack* UndoStack::instance_ = 0;
+
+UndoStack::UndoStack()
+  : StackBase()
+{
+  // setAutoDelete( true );
+}
+
+UndoStack* UndoStack::instance()
+{
+  if (!instance_)
+    instance_ = new UndoStack();
+  return instance_;
+}
+
+void UndoStack::undo()
+{
+  if (isEmpty())
+    return;
+    
+  Command *command = pop();
+  command->undo();
+  
+  RedoStack::instance()->push( command );
+}
+
+////////////////////
+// RedoStack
+
+RedoStack* RedoStack::instance_ = 0;
+
+RedoStack::RedoStack()
+{
+  mCommandStack.setAutoDelete( true );
+}
+
+RedoStack* RedoStack::instance()
+{
+  if (!instance_)
+    instance_ = new RedoStack();
+  return instance_;
+}
+
+void RedoStack::redo()
+{
+  Command *command;
+  if (isEmpty())
+    return;
+    
+  command = pop();
+  command->redo();
+  UndoStack::instance()->push( command );
+}
+
+#ifndef KAB_EMBEDDED
+#include "undo.moc"
+#endif //KAB_EMBEDDED