import org.eclipse.draw2d.Animation;
import org.eclipse.gmf.runtime.diagram.ui.actions.ActionIds;
import org.eclipse.gmf.runtime.diagram.ui.editparts.IGraphicalEditPart;
import org.eclipse.gmf.runtime.diagram.ui.requests.ArrangeRequest;
import org.eclipse.gmf.runtime.diagram.ui.services.layout.AbstractLayoutEditPartProvider;
import org.eclipse.sirius.diagram.DDiagram;
import org.eclipse.sirius.diagram.ui.edit.api.part.AbstractDDiagramEditPart;
import org.eclipse.sirius.diagram.ui.tools.api.layout.provider.CompoundLayoutProvider;
import org.eclipse.sirius.diagram.ui.tools.api.layout.provider.LayoutProvider;
import org.eclipse.sirius.diagram.ui.tools.api.layout.provider.LineLayoutProvider;

public class CustomLayoutProvider implements LayoutProvider {

	private static String UI_DIAGRAM_NAME = "ui_diagram";

	/** The GMF layout provider. */
	private CompoundLayoutProvider layoutProvider;
	
	private void arrangeLayout(IGraphicalEditPart container, String action){		
		
		// OK: only the first selection when view start 
		if(ActionIds.ACTION_ARRANGE_ALL.equals(action)){			
			ArrangeRequest layoutRequest = new ArrangeRequest(action);	
			Animation.markBegin();	
			container.performRequest(layoutRequest);
		    Animation.run(500);
		}
		
		// KO: I tried this, but i have exception (seems to be a loop causing the error)
		if(ActionIds.ACTION_ARRANGE_SELECTION.equals(action)){
			ArrangeRequest layoutRequest = new ArrangeRequest(action);						
			layoutRequest.setPartsToArrange(container.getChildren());
			Animation.markBegin();	
			container.performRequest(layoutRequest);
		    Animation.run(500);
		}
	    
	}
		
	public AbstractLayoutEditPartProvider getLayoutNodeProvider(IGraphicalEditPart container) {
		
		if (isUIDiagram(container)) {					
			
			if (this.layoutProvider == null) {
				System.out.println("Create Layout provider");
				this.layoutProvider = new CompoundLayoutProvider();
				LineLayoutProvider lineLayoutProvider = new LineLayoutProvider();
				lineLayoutProvider.getPadding().right = 10;
				lineLayoutProvider.setHorizontal(true);
				this.layoutProvider.addProvider(lineLayoutProvider);
				arrangeLayout(container, ActionIds.ACTION_ARRANGE_ALL);
								
			} else			
				arrangeLayout(container, ActionIds.ACTION_ARRANGE_SELECTION);
						
			return this.layoutProvider;
		} 
		return null;
	}

	public boolean provides(IGraphicalEditPart container) {
		return isUIDiagram(container);
	}

	private boolean isUIDiagram(IGraphicalEditPart container) {
		if (container instanceof AbstractDDiagramEditPart) {
			AbstractDDiagramEditPart editPart = (AbstractDDiagramEditPart) container;
			if (editPart.resolveSemanticElement() instanceof DDiagram) {
				DDiagram diagram = (DDiagram) editPart.resolveSemanticElement();
				return UI_DIAGRAM_NAME.equals(diagram.getDescription().getName());
			}
		} 
		return false;
	}

	@Override
	public boolean isDiagramLayoutProvider() {
		// TODO Auto-generated method stub
		return false;
	}
}