/*******************************************************************************
 * Copyright (c) 2003, 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
 *******************************************************************************/
/*
 * Created on Feb 2, 2004
 *
 * To change the template for this generated file go to
 * Window - Preferences - Java - Code Generation - Code and Comments
 */
package org.eclipse.jst.j2ee.internal.plugin;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.edit.provider.ItemProvider;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jem.util.emf.workbench.ProjectUtilities;
import org.eclipse.jface.viewers.IStructuredSelection;

/**
 * Utility class for retrieving the project from the specified selection
 */
public class UIProjectUtilities {

	/**
	 * @param selection
	 *            The current selection
	 * @return The first project (regardless of nature) in the selection
	 */
	public static IProject getSelectedProject(IStructuredSelection selection) {
		return getSelectedProject(selection, (String[]) null);
	}

	/**
	 * @param selection
	 *            The current selection
	 * @param expectedNatureId
	 *            The required Nature ID
	 * @return The first project, only if the first project has the given nature
	 */
	public static IProject getSelectedProject(IStructuredSelection selection, String expectedNatureId) {
		return getSelectedProject(selection, new String[] {expectedNatureId});
	}

	/**
	 * 
	 * @param selection
	 *            The current selection
	 * @param possibleNatureIds
	 *            A list of possible nature ids
	 * @return The first project selected, only if it has AT LEAST ONE of the possible nature ids
	 */
	public static IProject getSelectedProject(IStructuredSelection selection, String[] possibleNatureIds) {
		IProject[] projects = getAllSelectedProjects(selection, possibleNatureIds);
		if (projects == null || projects.length==0)
			return null;
		return projects[0];
	}

	/**
	 * 
	 * @param selection
	 *            The current selection
	 * @return All selected Projects, regardless of nature
	 */
	public static IProject[] getAllSelectedProjects(IStructuredSelection selection) {
		return getAllSelectedProjects(selection, (String[]) null);
	}

	/**
	 * 
	 * @param selection
	 *            The current selection
	 * @param expectedNatureId
	 *            The expected nature id
	 * @return All selected Projects which have the expected nature id
	 */
	public static IProject[] getAllSelectedProjects(IStructuredSelection selection, String expectedNatureId) {
		return getAllSelectedProjects(selection, new String[] {expectedNatureId});
	}

	/**
	 * 
	 * @param selection
	 *            The current selection
	 * @param possibleNatureIds
	 *            a list of possible nature ids
	 * @return All selected Projects which have AT LEAST ONE of the given nature ids
	 */
	public static IProject[] getAllSelectedProjects(IStructuredSelection selection, String[] possibleNatureIds) {
		if (selection != null && !selection.isEmpty()) {
			Object obj = null;
			List projects = new ArrayList();
			Iterator selectionIterator = selection.iterator();
			while (selectionIterator.hasNext()) {
				obj = selectionIterator.next();
				IProject project = null;
				if (obj instanceof IProject)
					project = (IProject) obj;
				else if (obj instanceof IAdaptable) {
					project = (IProject) ((IAdaptable) obj).getAdapter(IProject.class);
					if (project == null) {
						//Check for IJavaElements.
						IJavaElement javaElement = (IJavaElement) ((IAdaptable) obj).getAdapter(IJavaElement.class);
						if (javaElement != null) {
							project = javaElement.getJavaProject().getProject();
						}
					}
				}
				// Selection may not be adaptable to a project so continue trying to get selected project
				if (project == null && obj instanceof EObject)
					project = ProjectUtilities.getProject((EObject) obj);
				else if (project == null && obj instanceof ItemProvider) {
					Object temp = ((ItemProvider) obj).getParent(EObject.class);
					if (temp != null && temp instanceof EObject)
						project = ProjectUtilities.getProject((EObject) temp);
				}
				else if (project == null && obj instanceof IFile) 
					project = ProjectUtilities.getProject(obj);

				if (project != null && possibleNatureIds != null && possibleNatureIds.length > 0) {
					try {
						for (int i = 0; i < possibleNatureIds.length; i++)
							if (project.hasNature(possibleNatureIds[i]))
								projects.add(project);
					} catch (CoreException e) {
						//Ignore
					}
				} 
				
				else
					projects.add(project);
			}
			IProject[] finalProjects = new IProject[projects.size()];
			projects.toArray(finalProjects);
			return finalProjects;
		}
		return new IProject[0];
	}

}