/**
 * *******************************************************************************
 *  Copyright (c) 2017 Timing-Architects Embedded Systems GmbH and others.
 *  All rights reserved. This program and the accompanying materials
 *  are made available under the terms of the Eclipse Public License v1.0
 *  which accompanies this distribution, and is available at
 *  http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Timing-Architects Embedded Systems GmbH - initial API and implementation
 *
 * *******************************************************************************
 */
package org.eclipse.app4mc.amalthea.generator.ui;

import java.util.Arrays;

import org.eclipse.app4mc.amalthea.generator.configuration.DistributionType;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Spinner;

public abstract class DistributionGroup implements Listener {
	
	protected final Group group;
	protected final Spinner minSpinner;
	protected final Label minLabel;
	protected final Spinner avgSpinner;
	protected final Label avgLabel;
	protected final Spinner maxSpinner;
	protected final Label maxLabel;
	protected final Combo distributionCombo;
	
	public DistributionGroup(Composite parent, String name) {
		this.group = new Group(parent, SWT.NONE);
		this.group.setText(name);
	    GridLayout gridLayout = new GridLayout();
	    this.group.setLayout(gridLayout);
	    gridLayout.numColumns = 2;
	    GridData gridData = new GridData(GridData.FILL, GridData.CENTER, true, false);
		gridData.horizontalSpan = 2;
		this.group.setLayoutData(gridData);
		
		Label label = new Label(this.group, SWT.NONE);
	    label.setText("Distribution Type");
	    label.setLayoutData(new GridData(GridData.FILL, GridData.CENTER, true, false));
	    this.distributionCombo = new Combo(this.group, SWT.READ_ONLY);
	    this.distributionCombo.setItems(Arrays.stream(DistributionType.values()).map(Enum::name).toArray(String[]::new));
	    this.distributionCombo.select(0);
	    this.distributionCombo.addListener(SWT.Selection, this);
	    
		this.minLabel = new Label(this.group, SWT.NONE);
		this.minLabel.setText("Minimum");
		this.minLabel.setLayoutData(new GridData(GridData.FILL, GridData.CENTER, true, false));
	    this.minSpinner = new Spinner(this.group, SWT.NONE);
	    this.minSpinner.setMinimum(0);
	    this.minSpinner.setSelection(0);
	    
	    this.avgLabel = new Label(this.group, SWT.NONE);
	    this.avgLabel.setText("Average");
	    this.avgLabel.setLayoutData(new GridData(GridData.FILL, GridData.CENTER, true, false));
	    this.avgSpinner = new Spinner(this.group, SWT.NONE);
	    this.avgSpinner.setMinimum(0);
	    this.avgSpinner.setSelection(0);
	    
	    this.maxLabel = new Label(this.group, SWT.NONE);
	    this.maxLabel.setText("Maximum");
	    this.maxLabel.setLayoutData(new GridData(GridData.FILL, GridData.CENTER, true, false));
	    this.maxSpinner = new Spinner(this.group, SWT.NONE);
	    this.maxSpinner.setMinimum(0);
	    this.maxSpinner.setSelection(0);
	    
	    group.pack();
	}
	
	//TODO: guarantee that min <= avg <= max
	// fill ui elements with values of new distribution
	public void set(DistributionType type, int min, int avg, int max) {
		if(null != type) {
			this.distributionCombo.select(type.getValue());
			// enable/disable controls according distribution
			this.distributionCombo.notifyListeners(SWT.Selection, new Event());
			this.minSpinner.setSelection(min);
			this.avgSpinner.setSelection(avg);
			this.maxSpinner.setSelection(max);
		}
	}
	
	@Override
	public void handleEvent(Event event) {
		if(SWT.Selection == event.type) {
			if(this.distributionCombo == event.widget) {
				switch(this.distributionCombo.getSelectionIndex()) {
					case DistributionType.CONST_VALUE:
						this.minSpinner.setVisible(false);
						this.minLabel.setVisible(false);
						this.avgSpinner.setVisible(true);
						this.avgLabel.setVisible(true);
						this.maxSpinner.setVisible(false);
						this.maxLabel.setVisible(false);
						break;
					case DistributionType.UNIFORM_VALUE:
						this.minSpinner.setVisible(true);
						this.minLabel.setVisible(true);
						this.avgSpinner.setVisible(false);
						this.avgLabel.setVisible(false);
						this.maxSpinner.setVisible(true);
						this.maxLabel.setVisible(true);
						break;
					case DistributionType.WEIBULL_VALUE:
						this.minSpinner.setVisible(true);
						this.minLabel.setVisible(true);
						this.avgSpinner.setVisible(true);
						this.avgLabel.setVisible(true);
						this.maxSpinner.setVisible(true);
						this.maxLabel.setVisible(true);
						break;
					default:
						this.minSpinner.setVisible(false);
						this.minLabel.setVisible(false);
						this.avgSpinner.setVisible(false);
						this.avgLabel.setVisible(false);
						this.maxSpinner.setVisible(false);
						this.maxLabel.setVisible(false);
				}
			}
		}
	}
}