ltk/org.eclipse.statet.ltk.ui/src/org/eclipse/statet/ltk/ui/sourceediting/actions/SourceEditorOperationHandler.java

/*=============================================================================#
 # Copyright (c) 2013, 2019 Stephan Wahlbrink and others.
 # 
 # This program and the accompanying materials are made available under the
 # terms of the Eclipse Public License 2.0 which is available at
 # https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
 # which is available at https://www.apache.org/licenses/LICENSE-2.0.
 # 
 # SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
 # 
 # Contributors:
 #     Stephan Wahlbrink <sw@wahlbrink.eu> - initial API and implementation
 #=============================================================================*/

package org.eclipse.statet.ltk.ui.sourceediting.actions;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.ui.IWorkbenchPart;

import org.eclipse.statet.ecommons.ui.util.UIAccess;
import org.eclipse.statet.ecommons.ui.workbench.WorkbenchUIUtils;

import org.eclipse.statet.ltk.ui.sourceediting.ISourceEditor;


public class SourceEditorOperationHandler extends AbstractHandler {
	
	
	private final int viewerOperation;
	
	
	public SourceEditorOperationHandler(final int viewerOperation) {
		this.viewerOperation= viewerOperation;
	}
	
	
	protected ISourceEditor getSourceEditor(final Object context) {
		final IWorkbenchPart part= WorkbenchUIUtils.getActivePart(context);
		if (part == null) {
			return null;
		}
		return part.getAdapter(ISourceEditor.class);
	}
	
	@Override
	public void setEnabled(final Object evaluationContext) {
		final ISourceEditor editor= getSourceEditor(evaluationContext);
		if (editor == null) {
			setBaseEnabled(false);
			return;
		}
		final SourceViewer viewer= editor.getViewer();
		setBaseEnabled(UIAccess.isOkToUse(viewer)
				&& viewer.canDoOperation(this.viewerOperation) );
	}
	
	@Override
	public Object execute(final ExecutionEvent event) throws ExecutionException {
		final ISourceEditor editor= getSourceEditor(event.getApplicationContext());
		if (editor == null) {
			return null;
		}
		final SourceViewer viewer= editor.getViewer();
		if (UIAccess.isOkToUse(viewer)) {
			viewer.doOperation(this.viewerOperation);
		}
		return null;
	}
	
}