/*******************************************************************************
 * Copyright (c) 2006 Sybase, Inc. 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:
 *     Sybase, Inc. - initial API and implementation
 *******************************************************************************/
package org.eclipse.jst.jsf.common.ui.internal.utils;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.InputStream;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IWorkspaceRunnable;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.Path;
import org.eclipse.jst.jsf.common.ui.IFileFolderConstants;
import org.eclipse.jst.jsf.common.ui.JSFUICommonPlugin;
import org.eclipse.jst.jsf.common.ui.internal.logging.Logger;

/**
 * TODO: This class should be abstract to common utility.
 * 
 * This class implements management of resource in a workspace.
 */
public final class WorkspaceUtil {
	/** log instance */
	private static final Logger log = JSFUICommonPlugin
			.getLogger(WorkspaceUtil.class);

	private WorkspaceUtil() {
	    // no external instantiation
	}

	/**
	 * Create the given file in the workspace resource info tree.
	 * @param resource 
	 * @param contents 
	 */
	public static void ensureExistsInWorkspace(final IFile resource,
			final InputStream contents) {
		if (resource == null) {
			return;
		}
		IWorkspaceRunnable body = new IWorkspaceRunnable() {
			public void run(IProgressMonitor monitor) throws CoreException {
				if (resource.exists()) {
					resource.setContents(contents, true, false, null);
				} else {
					ensureExistsInWorkspace(resource.getParent(), true);
					resource.create(contents, true, null);
				}
			}
		};
		try {
			ResourcesPlugin.getWorkspace().run(body, null);
		} catch (CoreException e) {
			// Test.EclipseWorkspaceTest.Error.FileCreationInWorkspace = Fail in
			// creating file:{0} in the workspace resource info tree.
			log
					.error(
							"Test.EclipseWorkspaceTest.Error.FileCreationInWorkspace", resource.getName(), e);//$NON-NLS-1$
		}
	}

	/**
	 * Create the given file in the workspace resource info tree.
	 * @param resource 
	 * @param contents 
	 */
	public static void ensureExistsInWorkspace(IFile resource, String contents) {
		// FIXME: We'll need some way for handing file encoding.
		ensureExistsInWorkspace(resource, new ByteArrayInputStream(contents
				.getBytes()));
	}

	/**
	 * Create the given resource in the workspace resource info tree.
	 * @param resource 
	 * @param local 
	 */
	public static void ensureExistsInWorkspace(final IResource resource,
			final boolean local) {
		IWorkspaceRunnable body = new IWorkspaceRunnable() {
			public void run(IProgressMonitor monitor) throws CoreException {
				create(resource, local);
			}
		};
		try {
			ResourcesPlugin.getWorkspace().run(body, null);
		} catch (CoreException e) {
			// Test.EclipseWorkspaceTest.Error.ResourceCreationInWorkspace =
			// Fail in creating resource:{0} in the workspace resource info
			// tree.
			log
					.error(
							"Test.EclipseWorkspaceTest.Error.ResourceCreationInWorkspace", resource.getName(), e);//$NON-NLS-1$
		}
	}

	/**
	 * crate the resource if the resource is not existed, create a new one.
	 * 
	 * @param resource -
	 *            resource instance
	 * @param local -
	 *            a flag controlling whether or not the folder will be local
	 *            after the creation
	 * @throws CoreException
	 */
	protected static void create(final IResource resource, boolean local)
			throws CoreException {
		if (resource == null || resource.exists()) {
			return;
		}
		if (!resource.getParent().exists()) {
			create(resource.getParent(), local);
		}
		switch (resource.getType()) {
		case IResource.FILE:
			((IFile) resource).create(local ? new ByteArrayInputStream(
					new byte[0]) : null, true, getMonitor());
			break;
		case IResource.FOLDER:
			((IFolder) resource).create(true, local, getMonitor());
			break;
		case IResource.PROJECT:
			((IProject) resource).create(getMonitor());
			((IProject) resource).open(getMonitor());
			break;
		}
	}

	/**
	 * create and return a NullProgressMonitor
	 * 
	 * @return - NullProgressMonitor
	 */
	public static IProgressMonitor getMonitor() {
		return new NullProgressMonitor();
	}

	/**
	 * Get the project reference for a given path
	 * 
	 * @param path -
	 *            the path
	 * @return IProject - the project reference
	 */
	public static IProject getProjectFor(IPath path) {
		String[] segs = path.segments();
		String projectPath = new String();
		IProject[] projects = ResourcesPlugin.getWorkspace().getRoot()
				.getProjects();
		IProject project = null;
		for (int p = 0; p < projects.length; p++) {
			if (projects[p].isOpen()) {
				for (int s = 0; s < segs.length; s++) {
					if (segs[s].equalsIgnoreCase(projects[p].getName())) {
						// Once we have a match on the project name, then
						// the remainder of the segments equals the project path
						for (int s2 = s + 1; s2 < segs.length; s2++) {
							projectPath = projectPath
									+ IFileFolderConstants.PATH_SEPARATOR
									+ segs[s2];
						}
						project = projects[p];
						break;
					}
				}
			}
		}
		if (project == null) {
			return null;
		}

		// TODO: still don't understand why this refreshLocal is necessary
		// for now, going to only allow it if this method is called 
		// when the tree isn't locked.  This shouldn't cause a regression, since
		// when the call fails currently things keep on going due to the catch
		if (!project.getWorkspace().isTreeLocked())
		{
    		try {
    			project.refreshLocal(IResource.DEPTH_INFINITE, null);
    		} catch (CoreException e) {
                // TODO C.B.:pushing this down to a warning because it creates really
                // spurious output.  Don't know why we are calling refreshLocal at all.
                JSFUICommonPlugin.getLogger(WorkspaceUtil.class).info("Error.RefreshingLocal", e); //$NON-NLS-1$
    		}
		}
		
		IResource res = project.findMember(new Path(projectPath));
		if ((res != null) && (res.exists())) {
			return project;
		}
		return null;
	}

	/**
	 * Get the project reference for a given file
	 * 
	 * @param file -
	 *            the IFile file reference
	 * @return IProject - the project reference
	 */
	public static IProject getProjectFor(IFile file) {
		IPath testPath = new Path(file.getFullPath().toOSString());
		return getProjectFor(testPath);
	}

	/**
	 * Get the project reference for a given file
	 * 
	 * @param file -
	 *            the File file reference
	 * @return IProject - the project reference
	 */
	public static IProject getProjectFor(File file) {
		IPath testPath = new Path(file.getAbsolutePath());
		return getProjectFor(testPath);
	}

	/**
	 * Get the project-relative resource reference for a given path
	 * 
	 * @param path -
	 *            the path
	 * @return IResource - the project-relative resource
	 */
	public static IResource getProjectRelativeResource(IPath path) {
		String[] segs = path.segments();
		String projectPath = new String();
		IProject[] projects = ResourcesPlugin.getWorkspace().getRoot()
				.getProjects();
		IProject project = null;
		for (int p = 0; p < projects.length; p++) {
			if (projects[p].isOpen()) {
				for (int s = 0; s < segs.length; s++) {
					if (segs[s].equalsIgnoreCase(projects[p].getName())) {
						// Once we have a match on the project name, then
						// the remainder of the segments equals the project path
						for (int s2 = s + 1; s2 < segs.length; s2++) {
							projectPath = projectPath
									+ IFileFolderConstants.PATH_SEPARATOR
									+ segs[s2];
						}
						project = projects[p];
						break;
					}
				}
			}
		}
		if (project == null) {
			return null;
		}

		return project.getFile(projectPath);
	}

	/**
	 * Get the project-relative resource reference for a given file
	 * 
	 * @param file -
	 *            the File file reference
	 * @return IResource - the project-relative resource
	 */
	public static IResource getProjectRelativeResource(File file) {
		IPath testPath = new Path(file.getAbsolutePath());
		return getProjectRelativeResource(testPath);
	}
}