Copyright (c) 2013, 2016 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
    Chris McGee (IBM) - Bug 380325 - Release filesystem fragment providing Java 7 NIO2 support
    Sergey Prigogin (Google) - Bug 458006 - Fix tests that fail on Mac when filesystem.java7 is used
/*******************************************************************************
 * Copyright (c) 2013, 2016 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Chris McGee (IBM) - Bug 380325 - Release filesystem fragment providing Java 7 NIO2 support
 *     Sergey Prigogin (Google) - Bug 458006 - Fix tests that fail on Mac when filesystem.java7 is used
 *******************************************************************************/
package org.eclipse.core.internal.filesystem.local.nio;

import java.io.File;
import java.io.IOException;
import java.nio.file.*;
import org.eclipse.core.filesystem.EFS;
import org.eclipse.core.filesystem.IFileInfo;
import org.eclipse.core.filesystem.provider.FileInfo;
import org.eclipse.core.internal.filesystem.local.NativeHandler;

Default implementation of NativeHandler using only Java 7 API's. It can be
used in cases where neither a DOS/Windows nor POSIX file system could be
detected.
/**
 * Default implementation of NativeHandler using only Java 7 API's. It can be
 * used in cases where neither a DOS/Windows nor POSIX file system could be
 * detected.
 */
public class DefaultHandler extends NativeHandler {
	private static final int ATTRIBUTES = EFS.ATTRIBUTE_SYMLINK | EFS.ATTRIBUTE_LINK_TARGET // symbolic link support
			| EFS.ATTRIBUTE_READ_ONLY | EFS.ATTRIBUTE_EXECUTABLE; // based on Java API

	@Override
	public FileInfo fetchFileInfo(String fileName) {
		Path path = Paths.get(fileName);
		boolean exists = Files.exists(path);

		FileInfo info = new FileInfo();
		info.setExists(exists);

		// Even if it doesn't exist then check for symbolic link information.
		boolean isSymbolicLink = Files.isSymbolicLink(path);
		if (isSymbolicLink) {
			info.setAttribute(EFS.ATTRIBUTE_SYMLINK, true);
			try {
				info.setStringAttribute(EFS.ATTRIBUTE_LINK_TARGET, Files.readSymbolicLink(path).toString());
			} catch (IOException e) {
				// Leave the target alone.
				info.setError(IFileInfo.IO_ERROR);
			}
		}

		// Fill in the name of the file.
		// If the file system is case insensitive, we don't know the real name of the file.
		// Since obtaining the real name in such situation is pretty expensive, we use the name
		// passed as a parameter, which may differ by case from the real name of the file
		// if the file system is case insensitive.
		info.setName(path.toFile().getName());

		// Since we will be using a mixture of pre Java 7 API's which do not support the
		// retrieval of information for the symbolic link itself instead of the target
		// we will only support the following details if the symbolic link target exists.
		if (!exists)
			return info;

		try {
			info.setLastModified(Files.getLastModifiedTime(path).toMillis());
			info.setLength(Files.size(path));
			info.setDirectory(Files.isDirectory(path));

			info.setAttribute(EFS.ATTRIBUTE_READ_ONLY, !Files.isWritable(path) && Files.isReadable(path));
			info.setAttribute(EFS.ATTRIBUTE_EXECUTABLE, Files.isExecutable(path));
		} catch (IOException e) {
			// Leave alone and continue.
			info.setError(IFileInfo.IO_ERROR);
		}
		return info;
	}

	@Override
	public int getSupportedAttributes() {
		return ATTRIBUTES;
	}

	@Override
	public boolean putFileInfo(String fileName, IFileInfo info, int options) {
		// In all cases we will set the information on the symbolic link target
		// and not the symbolic link itself. This is consistent with the approach
		// taken above in fetchInfo.
		File file = new File(fileName);
		if (info.getAttribute(EFS.ATTRIBUTE_READ_ONLY)) {
			if (!file.setReadOnly())
				return false;
		} else {
			if (!file.setWritable(true))
				return false;
		}
		// If setExecutable succeeds, then the whole method succeeds.
		return file.setExecutable(info.getAttribute(EFS.ATTRIBUTE_EXECUTABLE));
	}
}