/*******************************************************************************
 * Copyright (c) 2011 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.wst.jsdt.ui.tests.utils;

import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.net.URL;

import org.eclipse.core.runtime.FileLocator;
import org.eclipse.wst.jsdt.ui.tests.internal.Activator;
import org.osgi.framework.Bundle;

/**
 * @author davidw
 * @see org.eclipse.jst.jsp.ui.tests.util.FileUtil
 */
public class FileUtil {
	public static String fLineSeparator = System.getProperty("line.separator");
	public static String fPathSeparator = System.getProperty("path.separator");
	public static String fFileSeparator = System.getProperty("file.separator");

	static File previousResultsDirectory = null;

	private static boolean notTriedYet = true;

	public static class DirFilenameFilter implements FilenameFilter {
		String startOfAcceptableNames;

		public DirFilenameFilter(String startOfDirName) {
			startOfAcceptableNames = startOfDirName;
		}

		/**
		 * @see java.io.FileFilter#accept(File)
		 */
		public boolean accept(File pathname, String filename) {
			// we'll just assume if it starts with right key, it is a directory ... for now
			return filename.startsWith(startOfAcceptableNames);
		}

	}

	public static File getPreviousResultsDirectory(String directoryRootName) throws IOException {
		if (previousResultsDirectory == null && notTriedYet) {
			Bundle bundle = Activator.getDefault().getBundle();
			URL url = bundle.getEntry("/");
			//String installPath = url.getPath();
			// add known file so URL method below can be used
			// (doesn't seem to work for directory?)
			URL totalURL = new URL(url, "plugin.xml");
			URL finalurl = FileLocator.toFileURL(totalURL);
			String finalFile = finalurl.getFile();
			File file = new File(finalFile);
			String finalPath = file.getParent();
			File pluginHomeDir = new File(finalPath);
			FilenameFilter dirFilter = new DirFilenameFilter(directoryRootName);
			File[] allDirs = pluginHomeDir.listFiles(dirFilter);

			// assume first in list is newest, then start looking with the 
			// second item ... just to avoid "null" case checking
			if (allDirs.length > 0) {
				File currentNewest = allDirs[0];
				for (int i = 1; i < allDirs.length; i++) {
					File current = allDirs[i];
					// NOTE: we go by modified date, not by the actual time stamp in name.
					// This should work for all normal cases, but may not if someone does some
					// "funny" copying, or updating from repository.
					if (current.lastModified() > currentNewest.lastModified()) {
						currentNewest = current;
					}
				}
				previousResultsDirectory = currentNewest;
			}
			notTriedYet = false;
		}
		return previousResultsDirectory;
	}

	public static File makeFileFor(String directory, String filename, String testResultsDirectoryPrefix) throws IOException {
		Bundle bundle = Activator.getDefault().getBundle();
		URL url = bundle.getEntry("/");
		URL localURL = FileLocator.toFileURL(url);
		String installPath = localURL.getPath();
		String totalDirectory = installPath + directory;
		String totalPath = totalDirectory + "/" + filename;
		URL totalURL = new URL(url, totalPath);
		//URL finalurl = Platform.asLocalURL(totalURL);
		String finalFile = totalURL.getFile();
		File file = new File(finalFile);
		String finalPath = file.getParent();
		File dir = new File(finalPath);
		if (!dir.exists()) {
			// a little safety net, be sure the previous newest directory
			// is initialized, just in case no one else has done so
			if (testResultsDirectoryPrefix != null && testResultsDirectoryPrefix.length() > 0) {
				FileUtil.getPreviousResultsDirectory(testResultsDirectoryPrefix);
			}
			// now its "safe" to make the new one
			dir.mkdirs();
		}
		return file;
	}

	/**
	 * Just a general utility method
	 * @param filename
	 * @return String
	 */
	public static String getExtension(String filename) {
		String extension = null;
		int dotPostion = filename.lastIndexOf('.');
		if (dotPostion > -1) {
			extension = filename.substring(dotPostion + 1);
		}
		else {
			extension = new String();
		}
		return extension;
	}

	public static void ensureExists(File dir) {
		if (!dir.exists()) {
			dir.mkdirs();
		}
	}

}