/* 
 * Copyright (c) 2008 Stiftung Deutsches Elektronen-Synchrotron, 
 * Member of the Helmholtz Association, (DESY), HAMBURG, GERMANY.
 *
 * THIS SOFTWARE IS PROVIDED UNDER THIS LICENSE ON AN "../AS IS" BASIS. 
 * WITHOUT WARRANTY OF ANY KIND, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED 
 * TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE AND 
 * NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE 
 * FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR 
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. SHOULD THE SOFTWARE PROVE DEFECTIVE 
 * IN ANY RESPECT, THE USER ASSUMES THE COST OF ANY NECESSARY SERVICING, REPAIR OR 
 * CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE. 
 * NO USE OF ANY SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER THIS DISCLAIMER.
 * DESY HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, 
 * OR MODIFICATIONS.
 * THE FULL LICENSE SPECIFYING FOR THE SOFTWARE THE REDISTRIBUTION, MODIFICATION, 
 * USAGE AND OTHER RIGHTS AND OBLIGATIONS IS INCLUDED WITH THE DISTRIBUTION OF THIS 
 * PROJECT IN THE FILE LICENSE.HTML. IF THE LICENSE IS NOT INCLUDED YOU MAY FIND A COPY 
 * AT HTTP://WWW.DESY.DE/LEGAL/LICENSE.HTM
 */
 package org.csstudio.sds.ui.internal.editor;

import org.csstudio.sds.internal.preferences.PreferenceConstants;
import org.csstudio.sds.ui.SdsUiPlugin;
import org.eclipse.jface.action.ContributionItem;
import org.eclipse.jface.action.ControlContribution;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Spinner;

/**
 * A {@link ControlContribution} to set the spacing of the grid from the {@link DisplayEditor}.
 * @author Kai Meyer
 *
 */
public final class GridSpacingContributionItem extends ControlContribution 
	implements SelectionListener, ModifyListener, IPropertyChangeListener {
	
	/**
	 * The {@link Spinner}.
	 */
	private Spinner _spacingSpinner;
	
	/**
	 * Constructor.
	 */
	public GridSpacingContributionItem() {
		super("GRID_SPACING");
		SdsUiPlugin.getCorePreferenceStore().addPropertyChangeListener(this);
	}
	
	/**
	 * Creates the control for this {@link ContributionItem}.
	 * @param parent The parent composite
	 * @return The Control
	 */
	@Override
	protected Control createControl(final Composite parent) {
		Composite comp = new Composite(parent, SWT.NONE);
		GridLayout layout = new GridLayout(2,false);
		layout.marginBottom = 0;
		layout.marginHeight = 0;
		layout.verticalSpacing = 0;
		layout.marginTop = 0;
		comp.setLayout(layout);
		Label label = new Label(comp, SWT.NONE);
		label.setText("Grid Space:");
		label.setLayoutData(new GridData(SWT.FILL,SWT.CENTER,false,false));
		int spacing = SdsUiPlugin.getCorePreferenceStore().getInt(
				PreferenceConstants.PROP_GRID_SPACING);
		_spacingSpinner = new Spinner(comp, SWT.NONE);
		_spacingSpinner.setMinimum(2);
		_spacingSpinner.setMaximum(500);
		_spacingSpinner.setToolTipText("The width of the grid in the editor");
		_spacingSpinner.setSelection(spacing);
		_spacingSpinner.addSelectionListener(this);
		_spacingSpinner.addModifyListener(this);
		_spacingSpinner.setLayoutData(new GridData(SWT.FILL,SWT.CENTER,false,false));
		comp.setBounds(comp.getBounds().x, comp.getBounds().y, computeWidth(_spacingSpinner)+computeWidth(label), comp.getBounds().height);
		return comp;
	}
	
	/**
	 * Computes the width required by control.
	 * @param control The control to compute width
	 * @return int The width required
	 */
	@Override
	protected int computeWidth(final Control control) {
		return control.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x;
	}
	
	/**
	 * Sets the preference value.
	 */
	private void setPreferenceValue() {
		String value = String.valueOf(_spacingSpinner.getSelection());
		SdsUiPlugin.getCorePreferenceStore().setValue(PreferenceConstants.PROP_GRID_SPACING, value);
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void widgetDefaultSelected(final SelectionEvent e) {
		this.setPreferenceValue();
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void widgetSelected(final SelectionEvent e) {
		this.setPreferenceValue();
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void modifyText(final ModifyEvent e) {
		this.setPreferenceValue();
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void propertyChange(final PropertyChangeEvent event) {
		if (event.getProperty().equals(PreferenceConstants.PROP_GRID_SPACING)) {
			Integer spacing;
			if (event.getNewValue() instanceof String) {
				spacing = new Integer((String) event.getNewValue());
			} else {
				spacing = (Integer) event.getNewValue();
			}
			if (spacing!=null && _spacingSpinner!=null && !_spacingSpinner.isDisposed()) {
				_spacingSpinner.setSelection(spacing);
			}
		}
	}
}