dsf/org.eclipse.cdt.examples.dsf/src/org/eclipse/cdt/examples/dsf/timers/TriggersVMNode.java

/*******************************************************************************
 * Copyright (c) 2006, 2015 Wind River Systems and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Wind River Systems - initial API and implementation
 *******************************************************************************/
package org.eclipse.cdt.examples.dsf.timers;

import java.util.concurrent.RejectedExecutionException;

import org.eclipse.cdt.dsf.concurrent.ConfinedToDsfExecutor;
import org.eclipse.cdt.dsf.concurrent.DsfRunnable;
import org.eclipse.cdt.dsf.concurrent.RequestMonitor;
import org.eclipse.cdt.dsf.service.DsfSession;
import org.eclipse.cdt.dsf.ui.viewmodel.VMDelta;
import org.eclipse.cdt.dsf.ui.viewmodel.datamodel.AbstractDMVMNode;
import org.eclipse.cdt.dsf.ui.viewmodel.datamodel.AbstractDMVMProvider;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.IElementPropertiesProvider;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.IPropertiesUpdate;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.LabelAttribute;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.LabelColumnInfo;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.LabelForeground;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.LabelImage;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.LabelText;
import org.eclipse.cdt.dsf.ui.viewmodel.properties.PropertiesBasedLabelProvider;
import org.eclipse.cdt.examples.dsf.DsfExamplesPlugin;
import org.eclipse.cdt.examples.dsf.timers.AlarmService.TriggerDMContext;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IChildrenUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IElementEditor;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IElementLabelProvider;
import org.eclipse.debug.internal.ui.viewers.model.provisional.ILabelUpdate;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IModelDelta;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IPresentationContext;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IViewerUpdate;
import org.eclipse.jface.viewers.CellEditor;
import org.eclipse.jface.viewers.ICellModifier;
import org.eclipse.jface.viewers.TextCellEditor;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.widgets.Composite;

/**
 * View model node that defines how alarm DMContexts are displayed in the view.  Alarm
 * nodes are fairly static, once they are created their label doesn't change.
 * @see TriggerDMContext
 */
@SuppressWarnings("restriction")
class TriggersVMNode extends AbstractDMVMNode
		implements IElementEditor, IElementPropertiesProvider, IElementLabelProvider {
	private static final String PROP_TRIGGER_NUMBER = "alarmNumber";
	private static final String PROP_TRIGGER_VALUE = "alarmTriggerValue";

	// Create and configure the label provider.
	private static final PropertiesBasedLabelProvider fgLabelProvider;
	static {
		fgLabelProvider = new PropertiesBasedLabelProvider();

		LabelColumnInfo idCol = new LabelColumnInfo(
				new LabelAttribute[] { new LabelText("Trigger #{0}", new String[] { PROP_TRIGGER_NUMBER }),
						new LabelForeground(new RGB(255, 0, 0)), new LabelImage(DsfExamplesPlugin.getDefault()
								.getImageRegistry().getDescriptor(DsfExamplesPlugin.IMG_ALARM)) });
		fgLabelProvider.setColumnInfo(TimersViewColumnPresentation.COL_ID, idCol);

		LabelColumnInfo valueCol = new LabelColumnInfo(
				new LabelAttribute[] { new LabelText("{0}", new String[] { PROP_TRIGGER_VALUE }) });
		fgLabelProvider.setColumnInfo(TimersViewColumnPresentation.COL_VALUE, valueCol);
	}

	private TriggerCellModifier fAlarmCellModifier;

	public TriggersVMNode(AbstractDMVMProvider provider, DsfSession session) {
		super(provider, session, TriggerDMContext.class);
	}

	@Override
	public String toString() {
		return "TriggersVMNode(" + getSession().getId() + ")";
	}

	@Override
	protected void updateElementsInSessionThread(final IChildrenUpdate update) {
		AlarmService alarmService = getServicesTracker().getService(AlarmService.class, null);
		if (alarmService == null) {
			handleFailedUpdate(update);
			return;
		}

		TriggerDMContext[] triggers = alarmService.getTriggers();
		fillUpdateWithVMCs(update, triggers);
		update.done();
	}

	@Override
	public void update(ILabelUpdate[] updates) {
		fgLabelProvider.update(updates);
	}

	@Override
	public void update(final IPropertiesUpdate[] updates) {
		// Switch to the session thread before processing the updates.
		try {
			getSession().getExecutor().execute(new DsfRunnable() {
				@Override
				public void run() {
					for (IPropertiesUpdate update : updates) {
						updatePropertiesInSessionThread(update);
					}
				}
			});
		} catch (RejectedExecutionException e) {
			for (IViewerUpdate update : updates) {
				handleFailedUpdate(update);
			}
		}
	}

	@ConfinedToDsfExecutor("getSession#getExecutor")
	private void updatePropertiesInSessionThread(final IPropertiesUpdate update) {
		// Find the trigger context in the element being updated
		TriggerDMContext triggerCtx = findDmcInPath(update.getViewerInput(), update.getElementPath(),
				TriggerDMContext.class);
		AlarmService alarmService = getServicesTracker().getService(AlarmService.class, null);

		// If either update or service are not valid, fail the update and return.
		if (triggerCtx == null || alarmService == null) {
			handleFailedUpdate(update);
			return;
		}

		// Calculate and set the update properties.
		int value = alarmService.getTriggerValue(triggerCtx);

		if (value == -1) {
			handleFailedUpdate(update);
			return;
		}

		update.setProperty(PROP_TRIGGER_NUMBER, triggerCtx.getTriggerNumber());
		update.setProperty(PROP_TRIGGER_VALUE, value);
		update.done();
	}

	@Override
	public CellEditor getCellEditor(IPresentationContext context, String columnId, Object element, Composite parent) {
		// Create a cell editor to modify the trigger value.
		if (TimersViewColumnPresentation.COL_VALUE.equals(columnId)) {
			return new TextCellEditor(parent);
		}
		return null;
	}

	// Note: this method is synchronized because IElementEditor.getCellModifier can be called
	// on any thread, even though in practice it should be only called on the UI thread.
	@Override
	public ICellModifier getCellModifier(IPresentationContext context, Object element) {
		// Create the cell modifier if needed.
		if (fAlarmCellModifier == null) {
			fAlarmCellModifier = new TriggerCellModifier(getSession());
		}
		return fAlarmCellModifier;
	}

	@Override
	public int getDeltaFlags(Object e) {
		// Since the label for triggers doesn't change, this node will generate
		// delta info only if the list of alarms is changed.
		if (e instanceof AlarmService.TriggersChangedEvent) {
			return IModelDelta.CONTENT;
		}
		return IModelDelta.NO_CHANGE;
	}

	@Override
	public void buildDelta(Object event, VMDelta parentDelta, int nodeOffset, RequestMonitor requestMonitor) {
		if (event instanceof AlarmService.TriggersChangedEvent) {
			// The list of alarms has changed, which means that the parent
			// node needs to refresh its contents, which in turn will re-fetch the
			// elements from this node.
			parentDelta.setFlags(parentDelta.getFlags() | IModelDelta.CONTENT);
		}
		requestMonitor.done();
	}

	@Override
	public void dispose() {
		if (fAlarmCellModifier != null) {
			fAlarmCellModifier.dispose();
		}
		super.dispose();
	}
}