/*******************************************************************************
 * Copyright (c) 2000, 2017 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
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.corext.util;

import java.io.File;
import java.net.URI;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.core.filesystem.EFS;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceStatus;
import org.eclipse.core.resources.ResourceAttributes;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.MultiStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.dltk.core.IModelStatusConstants;
import org.eclipse.dltk.internal.ui.DLTKUIStatus;
import org.eclipse.dltk.ui.DLTKUIPlugin;

public class Resources {

	private Resources() {
	}

	/**
	 * Checks if the given resource is in sync with the underlying file system.
	 *
	 * @param resource
	 *            the resource to be checked
	 * @return IStatus status describing the check's result. If <code>status.
	 * isOK()</code> returns <code>true</code> then the resource is in sync
	 */
	public static IStatus checkInSync(IResource resource) {
		return checkInSync(new IResource[] { resource });
	}

	/**
	 * Checks if the given resources are in sync with the underlying file
	 * system.
	 *
	 * @param resources
	 *            the resources to be checked
	 * @return IStatus status describing the check's result. If <code>status.
	 *  isOK() </code> returns <code>true</code> then the resources are in sync
	 */
	public static IStatus checkInSync(IResource[] resources) {
		IStatus result = null;
		for (int i = 0; i < resources.length; i++) {
			IResource resource = resources[i];
			if (!resource.isSynchronized(IResource.DEPTH_INFINITE)) {
				result = addOutOfSync(result, resource);
			}
		}
		if (result != null)
			return result;
		return new Status(IStatus.OK, DLTKUIPlugin.PLUGIN_ID, IStatus.OK, "", //$NON-NLS-1$
				null);
	}

	/**
	 * Makes the given resource committable. Committable means that it is
	 * writeable and that its content hasn't changed by calling
	 * <code>validateEdit</code> for the given resource on <tt>IWorkspace</tt>.
	 *
	 * @param resource
	 *            the resource to be checked
	 * @param context
	 *            the context passed to <code>validateEdit</code>
	 * @return status describing the method's result. If
	 *         <code>status.isOK()</code> returns <code>true</code> then the
	 *         resources are committable.
	 *
	 * @see org.eclipse.core.resources.IWorkspace#validateEdit(org.eclipse.core.resources.IFile[],
	 *      java.lang.Object)
	 */
	public static IStatus makeCommittable(IResource resource, Object context) {
		return makeCommittable(new IResource[] { resource }, context);
	}

	/**
	 * Makes the given resources committable. Committable means that all
	 * resources are writeable and that the content of the resources hasn't
	 * changed by calling <code>validateEdit</code> for a given file on
	 * <tt>IWorkspace</tt>.
	 *
	 * @param resources
	 *            the resources to be checked
	 * @param context
	 *            the context passed to <code>validateEdit</code>
	 * @return IStatus status describing the method's result. If <code>status.
	 * isOK()</code> returns <code>true</code> then the add resources are
	 *         committable
	 *
	 * @see org.eclipse.core.resources.IWorkspace#validateEdit(org.eclipse.core.resources.IFile[],
	 *      java.lang.Object)
	 */
	public static IStatus makeCommittable(IResource[] resources,
			Object context) {
		List<IFile> readOnlyFiles = new ArrayList<>();
		for (int i = 0; i < resources.length; i++) {
			IResource resource = resources[i];
			if (resource.getType() == IResource.FILE && isReadOnly(resource))
				readOnlyFiles.add((IFile) resource);
		}
		if (readOnlyFiles.size() == 0)
			return new Status(IStatus.OK, DLTKUIPlugin.PLUGIN_ID, IStatus.OK,
					"", null); //$NON-NLS-1$

		Map oldTimeStamps = createModificationStampMap(readOnlyFiles);
		IStatus status = ResourcesPlugin.getWorkspace().validateEdit(
				readOnlyFiles.toArray(new IFile[readOnlyFiles.size()]),
				context);
		if (!status.isOK())
			return status;

		IStatus modified = null;
		Map newTimeStamps = createModificationStampMap(readOnlyFiles);
		for (Iterator iter = oldTimeStamps.keySet().iterator(); iter
				.hasNext();) {
			IFile file = (IFile) iter.next();
			if (!oldTimeStamps.get(file).equals(newTimeStamps.get(file)))
				modified = addModified(modified, file);
		}
		if (modified != null)
			return modified;
		return new Status(IStatus.OK, DLTKUIPlugin.PLUGIN_ID, IStatus.OK, "", //$NON-NLS-1$
				null);
	}

	private static Map createModificationStampMap(List files) {
		Map map = new HashMap();
		for (Iterator iter = files.iterator(); iter.hasNext();) {
			IFile file = (IFile) iter.next();
			map.put(file, Long.valueOf(file.getModificationStamp()));
		}
		return map;
	}

	private static IStatus addModified(IStatus status, IFile file) {
		IStatus entry = DLTKUIStatus.createError(
				IModelStatusConstants.VALIDATE_EDIT_CHANGED_CONTENT,
				Messages.format(CorextMessages.Resources_fileModified,
						file.getFullPath().toString()),
				null);
		if (status == null) {
			return entry;
		} else if (status.isMultiStatus()) {
			((MultiStatus) status).add(entry);
			return status;
		} else {
			MultiStatus result = new MultiStatus(DLTKUIPlugin.PLUGIN_ID,
					IModelStatusConstants.VALIDATE_EDIT_CHANGED_CONTENT,
					CorextMessages.Resources_modifiedResources, null);
			result.add(status);
			result.add(entry);
			return result;
		}
	}

	private static IStatus addOutOfSync(IStatus status, IResource resource) {
		IStatus entry = new Status(IStatus.ERROR, ResourcesPlugin.PI_RESOURCES,
				IResourceStatus.OUT_OF_SYNC_LOCAL,
				Messages.format(CorextMessages.Resources_outOfSync,
						resource.getFullPath().toString()),
				null);
		if (status == null) {
			return entry;
		} else if (status.isMultiStatus()) {
			((MultiStatus) status).add(entry);
			return status;
		} else {
			MultiStatus result = new MultiStatus(ResourcesPlugin.PI_RESOURCES,
					IResourceStatus.OUT_OF_SYNC_LOCAL,
					CorextMessages.Resources_outOfSyncResources, null);
			result.add(status);
			result.add(entry);
			return result;
		}
	}

	/**
	 * This method is used to generate a list of local locations to be used in
	 * DnD for file transfers.
	 *
	 * @param resources
	 *            the array of resources to get the local locations for
	 * @return the local locations
	 */
	public static String[] getLocationOSStrings(IResource[] resources) {
		List<String> result = new ArrayList<>(resources.length);
		for (int i = 0; i < resources.length; i++) {
			IPath location = resources[i].getLocation();
			if (location != null)
				result.add(location.toOSString());
		}
		return result.toArray(new String[result.size()]);
	}

	/**
	 * Returns the location of the given resource. For local resources this is
	 * the OS path in the local file system. For remote resource this is the
	 * URI.
	 *
	 * @param resource
	 *            the resource
	 * @return the location string or <code>null</code> if the location URI of
	 *         the resource is <code>null</code>
	 */
	public static String getLocationString(IResource resource) {
		URI uri = resource.getLocationURI();
		if (uri == null)
			return null;
		return EFS.SCHEME_FILE.equalsIgnoreCase(uri.getScheme())
				? new File(uri).getAbsolutePath()
				: uri.toString();
	}

	public static boolean isReadOnly(IResource resource) {
		ResourceAttributes resourceAttributes = resource
				.getResourceAttributes();
		if (resourceAttributes == null) // not supported on this platform for
										// this resource
			return false;
		return resourceAttributes.isReadOnly();
	}

	static void setReadOnly(IResource resource, boolean readOnly) {
		ResourceAttributes resourceAttributes = resource
				.getResourceAttributes();
		if (resourceAttributes == null) // not supported on this platform for
										// this resource
			return;

		resourceAttributes.setReadOnly(readOnly);
		try {
			resource.setResourceAttributes(resourceAttributes);
		} catch (CoreException e) {
			DLTKUIPlugin.log(e);
		}
	}
}