/*******************************************************************************
 * Copyright (c) 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 - Initial API and implementation
 *******************************************************************************/
package org.eclipse.ptp.internal.rdt.ui;

import java.net.MalformedURLException;
import java.net.URL;

import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.resource.ImageRegistry;
import org.eclipse.ptp.rdt.ui.UIPlugin;
import org.eclipse.swt.graphics.Image;
import org.osgi.framework.Bundle;

/**
 * @author crecoskie
 *
 */
public class RDTPluginImages {
	public static final IPath ICONS_PATH= new Path("$nl$/icons"); //$NON-NLS-1$

	// The plugin registry
	private static ImageRegistry imageRegistry = new ImageRegistry(UIPlugin.getStandardDisplay());

	// Subdirectory (under the package containing this class) where 16 color images are
	private static URL fgIconBaseURL;

	static {
		try {
			fgIconBaseURL= new URL(UIPlugin.getDefault().getBundle().getEntry("/"), "icons/" ); //$NON-NLS-1$ //$NON-NLS-2$
		} catch (MalformedURLException e) {
			UIPlugin.log(e);
		}
	}	
	private static final String NAME_PREFIX= UIPlugin.PLUGIN_ID + '.';
	private static final int NAME_PREFIX_LENGTH= NAME_PREFIX.length();

	public static final String T_OBJ= "obj16/"; //$NON-NLS-1$
	public static final String T_WIZBAN= "wizban/"; //$NON-NLS-1$
	public static final String T_LCL=  "lcl16/"; //$NON-NLS-1$
	public static final String T_DLCL=  "dlcl16/"; //$NON-NLS-1$
	public static final String T_ELCL=  "elcl16/"; //$NON-NLS-1$
	public static final String T_TOOL= "tool16/"; //$NON-NLS-1$
	public static final String T_VIEW= "view16/"; //$NON-NLS-1$
	public static final String T_OVR= "ovr16/"; //$NON-NLS-1$
	
	public static final ImageDescriptor DESC_WIZBAN_NEW_REMOTE_C_PROJ = create(T_WIZBAN, "newremote_proj_wiz.gif"); //$NON-NLS-1$
	public static final ImageDescriptor DESC_WIZBAN_EXPORT_C_SETTINGS = create(T_WIZBAN, "exportc_settings_wiz.gif"); //$NON-NLS-1$
	public static final ImageDescriptor DESC_WIZBAN_IMPORT_C_SETTINGS = create(T_WIZBAN, "importc_settings_wiz.gif"); //$NON-NLS-1$
	
	private static ImageDescriptor createManaged(String prefix, String name) {
		return createManaged(imageRegistry, prefix, name);
	}
	
	private static ImageDescriptor createManaged(ImageRegistry registry, String prefix, String name) {
		ImageDescriptor result= ImageDescriptor.createFromURL(makeIconFileURL(prefix, name.substring(NAME_PREFIX_LENGTH)));
		registry.put(name, result);
		return result;
	}
	
	public static Image get(String key) {
		return imageRegistry.get(key);
	}
	
	private static ImageDescriptor create(String prefix, String name) {
		return ImageDescriptor.createFromURL(makeIconFileURL(prefix, name));
	}
	
	/*
	 * Creates an image descriptor for the given prefix and name in the JDT UI bundle. The path can
	 * contain variables like $NL$.
	 * If no image could be found, <code>useMissingImageDescriptor</code> decides if either
	 * the 'missing image descriptor' is returned or <code>null</code>.
	 * or <code>null</code>.
	 */
	private static ImageDescriptor create(String prefix, String name, boolean useMissingImageDescriptor) {
		IPath path= ICONS_PATH.append(prefix).append(name);
		return createImageDescriptor(UIPlugin.getDefault().getBundle(), path, useMissingImageDescriptor);
	}
	
	/*
	 * Creates an image descriptor for the given prefix and name in the JDT UI bundle. The path can
	 * contain variables like $NL$.
	 * If no image could be found, the 'missing image descriptor' is returned.
	 */
	private static ImageDescriptor createUnManaged(String prefix, String name) {
		return create(prefix, name, true);
	}
	
	private static URL makeIconFileURL(String prefix, String name) {
		StringBuffer buffer= new StringBuffer(prefix);
		buffer.append(name);
		try {
			return new URL(fgIconBaseURL, buffer.toString());
		} catch (MalformedURLException e) {
			UIPlugin.log(e);
			return null;
		}
	}
	
	/*
	 * Creates an image descriptor for the given path in a bundle. The path can contain variables
	 * like $NL$.
	 * If no image could be found, <code>useMissingImageDescriptor</code> decides if either
	 * the 'missing image descriptor' is returned or <code>null</code>.
	 * Added for 3.1.1.
	 */
	public static ImageDescriptor createImageDescriptor(Bundle bundle, IPath path, boolean useMissingImageDescriptor) {
		URL url= FileLocator.find(bundle, path, null);
		if (url != null) {
			return ImageDescriptor.createFromURL(url);
		}
		if (useMissingImageDescriptor) {
			return ImageDescriptor.getMissingImageDescriptor();
		}
		return null;
	}

	/**
	 * Sets the three image descriptors for enabled, disabled, and hovered to an action. The actions
	 * are retrieved from the *tool16 folders.
	 * 
	 * @param action	the action
	 * @param iconName	the icon name
	 */
	public static void setToolImageDescriptors(IAction action, String iconName) {
		setImageDescriptors(action, T_TOOL, iconName);
	}
	
	/**
	 * Sets the three image descriptors for enabled, disabled, and hovered to an action. The actions
	 * are retrieved from the *lcl16 folders.
	 * 
	 * @param action	the action
	 * @param iconName	the icon name
	 */
	public static void setLocalImageDescriptors(IAction action, String iconName) {
		setImageDescriptors(action, T_LCL, iconName);
	}

	/**
	 * Sets all available image descriptors for the given action.
	 */	
	public static void setImageDescriptors(IAction action, String type, String relPath) {
	    if (relPath.startsWith(NAME_PREFIX))
	        relPath= relPath.substring(NAME_PREFIX_LENGTH);
		action.setDisabledImageDescriptor(create("d" + type, relPath)); //$NON-NLS-1$
//		action.setHoverImageDescriptor(create("c" + type, relPath)); //$NON-NLS-1$
		action.setImageDescriptor(create("e" + type, relPath)); //$NON-NLS-1$

		// We are still not sure about this, let see TF results first.
		//		Use the managed version so that we ensure that there is no resource handle leaks
		//		Let the widget itself manage the disabled/hover attribution.  This was a huge leak
		//ImageDescriptor desc = getImageRegistry().getDescriptor(relPath);
		//if(desc == null) {
		//	desc = createManaged(T + "c" + type, relPath);
		//}	
		//action.setImageDescriptor(desc);
	}
	
	/**
	 * Helper method to access the image registry from the CUIPlugin class.
	 */
	static ImageRegistry getImageRegistry() {
		return imageRegistry;
	}
}