package org.eclipse.stem.util.loggers;

/*******************************************************************************
 * Copyright (c) 2006, 2007, 2008 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
 *******************************************************************************/

import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.ui.plugin.AbstractUIPlugin;
import org.osgi.framework.BundleContext;

/**
 * The activator class controls the plug-in life cycle
 */
public class Activator extends AbstractUIPlugin {

	/**
	 * The plug-in ID
	 */
	public static final String PLUGIN_ID = "org.eclipse.stem.util.loggers"; //$NON-NLS-1$

	// The shared instance
	private static Activator plugin;

	/**
	 * The constructor
	 */
	public Activator() {
		plugin = this;
	}

	/**
	 * @see org.eclipse.ui.plugin.AbstractUIPlugin#start(org.osgi.framework.BundleContext)
	 */
	public void start(BundleContext context) throws Exception {
		super.start(context);
	}

	/**
	 * @see org.eclipse.ui.plugin.AbstractUIPlugin#stop(org.osgi.framework.BundleContext)
	 */
	public void stop(BundleContext context) throws Exception {
		plugin = null;
		super.stop(context);
	}

	/**
	 * Returns the shared instance
	 * 
	 * @return the shared instance
	 */
	public static Activator getDefault() {
		return plugin;
	}

	/**
	 * Returns an image descriptor for the image file at the given plug-in
	 * relative path
	 * 
	 * @param path
	 *            the path
	 * @return the image descriptor
	 */
	public static ImageDescriptor getImageDescriptor(String path) {
		return imageDescriptorFromPlugin(PLUGIN_ID, path);
	}

	/**
	 * Log an error to the ILog for this plugin
	 * 
	 * @param message
	 *            the localized error message text
	 * @param exception
	 *            the associated exception, or null
	 */
	public static void logError(String message, Throwable exception) {
		// Do we have a plugin?
		if (plugin != null) {
			// Yes
			plugin.getLog().log(
					new Status(IStatus.ERROR, plugin.getBundle()
							.getSymbolicName(), 0, message, exception));
		} else {
			// No
			System.out.println(message);
			// Exception?
			if (exception != null) {
				// Yes
				System.out.println(exception.getMessage());
			} // if
		}
	} // logError

	/**
	 * Log information to the ILog for this plugin
	 * 
	 * @param message
	 *            the localized information message text
	 * @param exception
	 *            the associated exception, or null
	 */
	public static void logInformation(String message, Throwable exception) {
		// Do we have a plugin?
		if (plugin != null) {
			// Yes
			plugin.getLog().log(
					new Status(IStatus.INFO, plugin.getBundle()
							.getSymbolicName(), 0, message, exception));
		} else {
			// No
			System.out.println(message);
			// Exception?
			if (exception != null) {
				// Yes
				System.out.println(exception.getMessage());
			} // if
		}
	} // logInformation
	
	/**
	 * Log information to the ILog for this plugin
	 * The method is overloaded to allow for logInformation without an error 
	 * method sets the error to null. This should be used instead of System.out.println
	 * throughout the code.
	 * @param message
	 *            the localized information message text
	 *
	 */
	public static void logInformation(String message) {
		if(plugin != null) 
			plugin.getLog().log(
				new Status(IStatus.INFO, plugin.getBundle().getSymbolicName(),
						0, message, null));
			else 
				// No
				System.out.println(message);
	} // logInformation
	
} // Activator