/*******************************************************************************
 * Copyright (c) 2000, 2006 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.jdt.internal.ui.actions;

import org.eclipse.core.runtime.CoreException;

import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IProjectNature;
import org.eclipse.core.resources.IResource;

import org.eclipse.swt.widgets.Shell;

import org.eclipse.jface.dialogs.MessageDialog;

import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.IPackageFragment;
import org.eclipse.jdt.core.IPackageFragmentRoot;
import org.eclipse.jdt.core.JavaCore;

import org.eclipse.jdt.internal.corext.refactoring.util.ResourceUtil;
import org.eclipse.jdt.internal.corext.util.Messages;

import org.eclipse.jdt.internal.ui.javaeditor.JavaEditor;

/*
 * http://dev.eclipse.org/bugs/show_bug.cgi?id=19104
 */
public class ActionUtil {
	
	private ActionUtil(){
	}

	//bug 31998	we will have to disable renaming of linked packages (and cus)
	public static boolean mustDisableJavaModelAction(Shell shell, Object element) {
		if (!(element instanceof IPackageFragment) && !(element instanceof IPackageFragmentRoot))
			return false;
		
		IResource resource= ResourceUtil.getResource(element);
		if ((resource == null) || (! (resource instanceof IFolder)) || (! resource.isLinked()))
			return false;
			
		MessageDialog.openInformation(shell, ActionMessages.ActionUtil_not_possible, ActionMessages.ActionUtil_no_linked); 
		return true;
	}
	
	public static boolean isProcessable(Shell shell, JavaEditor editor) {
		if (editor == null)
			return true;
		IJavaElement input= SelectionConverter.getInput(editor);
		// if a Java editor doesn't have an input of type Java element
		// then it is for sure not on the build path
		if (input == null) {
			MessageDialog.openInformation(shell, 
				ActionMessages.ActionUtil_notOnBuildPath_title,  
				ActionMessages.ActionUtil_notOnBuildPath_message); 
			return false;
		}
		return isProcessable(shell, input);
	}
	
	public static boolean isProcessable(Shell shell, Object element) {
		if (!(element instanceof IJavaElement))
			return true;
			
		if (isOnBuildPath((IJavaElement)element))
			return true;
		MessageDialog.openInformation(shell, 
			ActionMessages.ActionUtil_notOnBuildPath_title,  
			ActionMessages.ActionUtil_notOnBuildPath_message); 
		return false;
	}

	public static boolean isOnBuildPath(IJavaElement element) {	
        //fix for bug http://dev.eclipse.org/bugs/show_bug.cgi?id=20051
        if (element.getElementType() == IJavaElement.JAVA_PROJECT)
            return true;
		IJavaProject project= element.getJavaProject();
		try {
			if (!project.isOnClasspath(element))
				return false;
			IProject resourceProject= project.getProject();
			if (resourceProject == null)
				return false;
			IProjectNature nature= resourceProject.getNature(JavaCore.NATURE_ID);
			// We have a Java project
			if (nature != null)
				return true;
		} catch (CoreException e) {
		}
		return false;
	}

	public static boolean areProcessable(Shell shell, IJavaElement[] elements) {
		for (int i= 0; i < elements.length; i++) {
			if (! isOnBuildPath(elements[i])) {
				MessageDialog.openInformation(shell, 
						ActionMessages.ActionUtil_notOnBuildPath_title,  
						Messages.format(ActionMessages.ActionUtil_notOnBuildPath_resource_message, new Object[] {elements[i].getPath()}));
				return false;
			}
		}
		return true;
	}
}