/*
    *  Copyright 2012 Chris Pheby
    *
    *  Licensed under the Apache License, Version 2.0 (the "License");
    *  you may not use this file except in compliance with the License.
    *  You may obtain a copy of the License at
    *
    *      http://www.apache.org/licenses/LICENSE-2.0
    *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   */
  package org.jadira.scanner.core.helper;
  
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.URISyntaxException;
  import java.net.URL;
  import java.util.WeakHashMap;
  
  import org.jadira.scanner.core.exception.FileAccessException;
  
  import de.schlichtherle.io.ArchiveDetector;
  import de.schlichtherle.io.ArchiveException;
  
  public final class FileUtils {
  
      private static final WeakHashMap<String, de.schlichtherle.io.File> FILE_CACHE = new WeakHashMap<String, de.schlichtherle.io.File>();
  	
  	private FileUtils() {
  	}
  
  	public static File getFileForPathName(String pathName, File parentFile) throws FileAccessException {
  
  		final String directoryPathName;
  		if (!pathName.contains("/")) {
  			directoryPathName = pathName.replace('.', de.schlichtherle.io.File.separatorChar);
  		} else {
  			directoryPathName = pathName.replace('/', de.schlichtherle.io.File.separatorChar);
  		}
  
  		String filePath = parentFile.getPath() + de.schlichtherle.io.File.separatorChar + directoryPathName;
  		de.schlichtherle.io.File cachedFile = FILE_CACHE.get(filePath);
  		if (cachedFile != null) {
  			return cachedFile;
  		}
  
  		de.schlichtherle.io.File resolvedFile = new de.schlichtherle.io.File(filePath, ArchiveDetector.ALL);
  		if (resolvedFile.exists()) {
  			FILE_CACHE.put(filePath, resolvedFile);
  			return resolvedFile;
  		} else {
  			return null;
  		}
  	}
  	
  	public static File getFileForPathName(String pathName, URL url) throws FileAccessException {
  
  		File parentFile = getFileFromURL(url);
  
  		return getFileForPathName(pathName, parentFile);
  	}
  
  	public static File getFileFromURL(URL url) throws FileAccessException {
  
  		String pathString = url.toString();
  		if (pathString.endsWith("!/")) {
  			pathString = pathString.substring(4);
  			pathString = pathString.substring(0, pathString.length() - 2);
  		}
  
  		File retVal;
  
  		try {
  			if (pathString.endsWith("/")) {
  				retVal = new File(url.toURI());
  			} else {
  				retVal = new de.schlichtherle.io.File(new File(url.toURI()), ArchiveDetector.ALL);
  			}
  		} catch (URISyntaxException e) {
  			throw new FileAccessException("Could not derive file from URL: " + url, e);
  		}
  
  		return retVal;
  	}
  
      public static <T> T doWithFile(File file, FileInputStreamOperation<T> callback) {
      	
      	InputStream fiStream = null;
  		
  		try {
  			if (file instanceof de.schlichtherle.io.File) {
  				fiStream = new de.schlichtherle.io.FileInputStream(file);
 			} else {
 				fiStream = new FileInputStream(file);
 			}
 			return callback.execute(file.getPath(), fiStream);
 		} catch (FileNotFoundException e) {
 			throw new FileAccessException("Could not find referenced file: " + file.getPath(), e);
 		} finally {
 			
 			try {
 				if (fiStream != null) {
 					fiStream.close();
 					
 				}
 			} catch (IOException e) {
 			} finally {
 			
 				if (file instanceof de.schlichtherle.io.File) {
 					try {
 					    de.schlichtherle.io.File.umount(); //TVFS.umount((de.schlichtherle.io.File)file);
 					} catch (ArchiveException e) { // FsSyncException e) {
 					}
 				}
 			}
 		}
     }
 }