/**
 * Copyright 2004-2016 Riccardo Solmi. All rights reserved.
 * This file is part of the Whole Platform.
 *
 * The Whole Platform is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * The Whole Platform is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with the Whole Platform. If not, see <http://www.gnu.org/licenses/>.
 */
package org.whole.lang.e4.ui.jobs;

import java.lang.reflect.InvocationTargetException;

import org.eclipse.e4.core.contexts.IEclipseContext;
import org.eclipse.e4.ui.di.UISynchronize;
import org.whole.lang.bindings.IBindingManager;
import org.whole.lang.e4.ui.util.E4Utils;
import org.whole.lang.model.IEntity;
import org.whole.lang.operations.IOperationProgressMonitor;
import org.whole.lang.operations.OperationCanceledException;
import org.whole.lang.ui.viewers.IEntityPartViewer;
import org.whole.lang.util.BehaviorUtils;

/**
 * @author Enrico Persiani
 */
public class DeriveModelRunnable extends AbstractRunnableWithProgress {
	protected String functionUri;
	protected boolean functionIsTransactional;
	protected ShowingPolicy resultShowingPolicy;

	public DeriveModelRunnable(IEclipseContext context, IBindingManager bm, String label,
			String functionUri, boolean functionIsTransactional, ShowingPolicy resultShowingPolicy) {
		super(context, bm, label);
		this.functionUri = functionUri;
		this.functionIsTransactional = functionIsTransactional;
		this.resultShowingPolicy = resultShowingPolicy;
	}

	@Override
	protected boolean isTransactional() {
		return this.functionIsTransactional;
	}

	@Override
	public void run(IOperationProgressMonitor pm) throws InvocationTargetException, InterruptedException {
		pm.beginTask("Deriving...", IOperationProgressMonitor.TOTAL_WORK);
		try {
			bm.wEnterScope();
			bm.wDefValue("debug#reportModeEnabled", false);
			final IEntity result = BehaviorUtils.apply(functionUri, bm.wGet("self"), bm);
			UISynchronize synchronize = context.get(UISynchronize.class);
			if (synchronize == null)
				return;

			synchronize.asyncExec(new Runnable() {
				public void run() {
					updateUI(result);
				}
			});
		} catch (OperationCanceledException e) {
			// gracefully terminate execution
		} finally {
			bm.wExitScope();
			pm.endTask();
		}
	}
	
	protected void updateUI(IEntity result) {
		IEntityPartViewer viewer = context.get(IEntityPartViewer.class);
		if (viewer == null)
			return;

		switch (resultShowingPolicy) {
		case MANDATORY:
			if (result != null)
				viewer.setContents(result);
			else
				viewer.setContents(null, E4Utils.createErrorStatusContents("missing mandatory results", "review derivation code"));
			break;

		case OPTIONAL:
			if (result != null)
				viewer.setContents(result);
			else
				viewer.setContents(null, E4Utils.createEmptyStatusContents());
			break;

		default:
		case IGNORABLE:
			viewer.setContents(null, E4Utils.createEmptyStatusContents());
			break;
		}
	}
}