/*******************************************************************************
 * Copyright (c) 2004, 2005 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.gef.examples.text.actions;

import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.util.Assert;

import org.eclipse.gef.internal.InternalImages;

/**
 * @since 3.1
 */
public class BooleanStyleAction 
	extends Action 
{

protected String property;
protected StyleService service;
private StyleListener styleListener = new StyleListener() {
	public void styleChanged(String styleID) {
		if (styleID == null || styleID.equals(getId()))
			refresh();
	}
};

public BooleanStyleAction(StyleService service, String styleID, String property) {
	setStyleService(service);
	setId(styleID);
	this.property = property;
	configureStyleAction(this);
}

protected boolean calculateEnabled() {
	return service.getStyleState(getId()) == StyleService.STATE_EDITABLE;
}

static void configureStyleAction(IAction a) {
	String styleID = a.getId();
	a.setActionDefinitionId(styleID);
	if (styleID.equals(TextActionConstants.STYLE_BOLD)) {
		a.setText("Bold");
		a.setImageDescriptor(InternalImages.DESC_BOLD);
	} else if (styleID.equals(TextActionConstants.STYLE_ITALIC)) {
		a.setText("Italics");
		a.setImageDescriptor(InternalImages.DESC_ITALIC);
	} else if (styleID.equals(TextActionConstants.STYLE_UNDERLINE)) {
		a.setText("Underline");
		a.setImageDescriptor(InternalImages.DESC_UNDERLINE);
	} else if (styleID.equals(TextActionConstants.BLOCK_ALIGN_CENTER)){
		a.setText("Center");
		a.setImageDescriptor(InternalImages.DESC_BLOCK_ALIGN_CENTER);
	} else if (styleID.equals(TextActionConstants.BLOCK_ALIGN_LEFT)){
		a.setText("Left");
		a.setImageDescriptor(InternalImages.DESC_BLOCK_ALIGN_LEFT);
	} else if (styleID.equals(TextActionConstants.BLOCK_ALIGN_RIGHT)){
		a.setText("Right");
		a.setImageDescriptor(InternalImages.DESC_BLOCK_ALIGN_RIGHT);
	} else if (styleID.equals(TextActionConstants.BLOCK_LTR)){
		a.setText("Left to Right");
		a.setImageDescriptor(InternalImages.DESC_BLOCK_LTR);
	} else if (styleID.equals(TextActionConstants.BLOCK_RTL)){
		a.setText("Right to Left");
		a.setImageDescriptor(InternalImages.DESC_BLOCK_RTL);
	} else {
		throw new RuntimeException("The given style ID was not recognized"); //$NON-NLS-1$
	}
}
	
public void run() {
	service.setStyle(property, isChecked() ? Boolean.TRUE : Boolean.FALSE);
}

// should only be called once
private void setStyleService(StyleService styleService) {
	Assert.isNotNull(styleService);
	service = styleService;
	// no need to remove this listener; it will be GCed when the editor's closed
	service.addStyleListener(styleListener);
}

public void refresh() {
	setChecked(service.getStyle(property).equals(Boolean.TRUE));
	setEnabled(service.getStyleState(property).equals(StyleService.STATE_EDITABLE));
}

}