package org.csstudio.sds.components.model.eventing;

import org.csstudio.sds.components.model.BargraphModel;
import org.csstudio.sds.eventhandling.AbstractWidgetPropertyPostProcessor;
import org.csstudio.sds.model.commands.HidePropertyCommand;
import org.csstudio.sds.model.commands.ShowPropertyCommand;
import org.eclipse.gef.commands.Command;
import org.eclipse.gef.commands.CompoundCommand;

/**
 * Post Processor that hides properties for
 * {@link BargraphModel#PROP_SCALE_SECTION_COUNT} and
 * {@link BargraphModel#PROP_SHOW_VALUES} depending on property
 * {@link BargraphModel#PROP_SHOW_SCALE}
 * 
 * @author Sven Wende
 * 
 */
public class BargraphShowScalePostProcessor extends AbstractWidgetPropertyPostProcessor<BargraphModel> {

	@Override
	protected Command doCreateCommand(BargraphModel widget) {
		assert widget != null : "widget != null";
		return new EnsureInvariantsCommand(widget, BargraphModel.PROP_SHOW_SCALE);
	}

	private static final class EnsureInvariantsCommand extends Command {
		private final BargraphModel widget;
		private final String propertyId;
		private CompoundCommand chain;

		private EnsureInvariantsCommand(BargraphModel widget, String propertyId) {
			this.widget = widget;
			this.propertyId = propertyId;
		}

		@Override
		public void execute() {
			if (chain == null) {
				chain = new CompoundCommand();

				int optionProperty = widget.getArrayOptionProperty(propertyId);

				String[] propertyIds = new String[] { BargraphModel.PROP_SCALE_SECTION_COUNT, BargraphModel.PROP_SHOW_VALUES };

				String selectedString = BargraphModel.SHOW_LABELS[optionProperty];
				if ("None".equals(selectedString)) {
					for (String propertyId : propertyIds) {
						chain.add(new HidePropertyCommand(widget, propertyId, this.propertyId));
					}
				} else {
					for (String propertyId : propertyIds) {
						chain.add(new ShowPropertyCommand(widget, propertyId, this.propertyId));
					}
				}
			}

			chain.execute();
		}

		@Override
		public void undo() {
			chain.undo();
		}
	}

}