/*
* DirtyState.java
*
* Copyright (C) 2009-12 by RStudio, Inc.
*
* Unless you have received this program directly from RStudio pursuant
* to the terms of a commercial license agreement with RStudio, then
* this program is licensed to you under the terms of version 3 of the
* GNU Affero General Public License. This program is distributed WITHOUT
* ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING THOSE OF NON-INFRINGEMENT,
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Please refer to the
* AGPL (http://www.gnu.org/licenses/agpl-3.0.txt) for more details.
*
*/
package org.rstudio.studio.client.workbench.views.source.model;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.event.logical.shared.HasValueChangeHandlers;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.GwtEvent;
import com.google.gwt.event.shared.HandlerManager;
import com.google.gwt.event.shared.HandlerRegistration;
import org.rstudio.studio.client.common.ReadOnlyValue;
import org.rstudio.studio.client.workbench.views.source.editors.text.DocDisplay;
import org.rstudio.studio.client.workbench.views.source.editors.text.events.UndoRedoEvent;
import org.rstudio.studio.client.workbench.views.source.editors.text.events.UndoRedoHandler;
public class DirtyState implements ReadOnlyValue<Boolean>
{
public DirtyState(DocDisplay editor, boolean initialState)
{
editor_ = editor;
if (initialState)
markDirty(false);
else
markClean();
editor_.addUndoRedoHandler(new UndoRedoHandler()
{
public void onUndoRedo(UndoRedoEvent event)
{
if (editor_.checkCleanStateToken(cleanUndoStateToken_))
markClean();
else
markDirty(true);
}
});
}
public void markDirty(boolean allowUndoBackToClean)
{
if (!allowUndoBackToClean)
cleanUndoStateToken_ = JavaScriptObject.createObject();
if (!value_)
{
value_ = true;
fire(value_);
}
}
public void markClean()
{
cleanUndoStateToken_ = editor_.getCleanStateToken();
if (value_)
{
value_ = false;
fire(value_);
}
}
public Boolean getValue()
{
return value_;
}
public HandlerRegistration addValueChangeHandler(ValueChangeHandler<Boolean> handler)
{
return handlers_.addHandler(ValueChangeEvent.getType(), handler);
}
public void fireEvent(GwtEvent<?> event)
{
handlers_.fireEvent(event);
}
private void fire(boolean value)
{
ValueChangeEvent.fire(
new HasValueChangeHandlers<Boolean>()
{
public HandlerRegistration addValueChangeHandler(
ValueChangeHandler<Boolean> handler)
{
throw new UnsupportedOperationException();
}
public void fireEvent(GwtEvent<?> event)
{
DirtyState.this.fireEvent(event);
}
}, value);
}
private final HandlerManager handlers_ = new HandlerManager(this);
private JavaScriptObject cleanUndoStateToken_;
private boolean value_;
private final DocDisplay editor_;
}