/**
    * Copyright 2010-2014 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.common.util.file;
  
  import static com.google.common.collect.Lists.transform;
  import static org.kuali.common.util.base.Exceptions.illegalState;
  import static org.kuali.common.util.base.Precondition.checkIsDir;
  import static org.kuali.common.util.base.Precondition.checkNotBlank;
  import static org.kuali.common.util.base.Precondition.checkNotNull;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.List;
  
  import com.google.common.base.Function;
  import com.google.common.collect.ImmutableList;
  import com.google.common.collect.Ordering;
  
  /**
   * @deprecated
   */
  @Deprecated
  public final class Files {
  
  	public static long sumFileLengths(Iterable<File> files) {
  		long sum = 0;
  		for (File file : files) {
  			sum += file.length();
  		}
  		return sum;
  	}
  
  	public static List<File> canonicalList(File dir) {
  		return transform(listFiles(checkIsDir(dir, "dir")), canonical());
  	}
  
  	public static File currentWorkingDirectory() {
  		return getCanonicalFile(".");
  	}
  
  	public static Function<File, File> canonical() {
  		return FileFunction.CANONICAL;
  	}
  
  	public static Function<File, Long> length() {
  		return LongFunction.LENGTH;
  	}
  
  	public static Function<File, Long> lastModified() {
  		return LongFunction.LAST_MODIFIED;
  	}
  
  	public static File getCanonicalFile(File file) {
  		return canonical().apply(file);
  	}
  
  	public static File getCanonicalFile(String path) {
  		return getCanonicalFile(new File(checkNotBlank(path, "path")));
  	}
  
  	public static File getCanonicalFile(File parent, String child) {
  		return getCanonicalFile(new File(checkNotNull(parent, "parent"), checkNotBlank(child, "child")));
  	}
  
  	/**
  	 * Return an immutable list of files from <code>dir</code>, sorted naturally
  	 * 
  	 * @throws IllegalArgumentException
  	 *             if dir is null, does not exist, or exists but is not a directory
  	 */
  	public static List<File> listFiles(File dir) {
  		return listFiles(dir, Ordering.<File> natural());
  	}
  
  	/**
  	 * Return an immutable list of files from <code>dir</code>, sorted by size
  	 * 
  	 * @throws IllegalArgumentException
  	 *             if dir is null, does not exist, or exists but is not a directory
  	 */
  	public static List<File> listFilesBySize(File dir) {
  		return listFiles(dir, Ordering.natural().onResultOf(length()));
  	}
  
  	/**
  	 * Return an immutable list of files from <code>dir</code>, sorted by last modified timestamp
 	 * 
 	 * @throws IllegalArgumentException
 	 *             if dir is null, does not exist, or exists but is not a directory
 	 */
 	public static List<File> listFilesByLastModified(File dir) {
 		return listFiles(dir, Ordering.natural().onResultOf(lastModified()));
 	}
 
 	/**
 	 * Return an immutable list of files from <code>dir</code>, sorted by <code>ordering</code>
 	 * 
 	 * @throws IllegalArgumentException
 	 *             if dir is null, does not exist, or exists but is not a directory
 	 */
 	public static List<File> listFiles(File dir, Ordering<File> ordering) {
 		checkIsDir(dir, "dir");
 		return ordering.immutableSortedCopy(ImmutableList.copyOf(dir.listFiles()));
 	}
 
 	private enum FileFunction implements Function<File, File> {
 		CANONICAL {
 			@Override
 			public File apply(File file) {
 				try {
 					return file.getCanonicalFile();
 				} catch (IOException e) {
 					throw illegalState(e);
 				}
 			}
 		},
 		PARENT {
 			@Override
 			public File apply(File file) {
 				return file.getParentFile();
 			}
 		},
 		ABSOLUTE {
 			@Override
 			public File apply(File file) {
 				return file.getAbsoluteFile();
 			}
 		}
 	}
 
 	private enum LongFunction implements Function<File, Long> {
 		LENGTH {
 			@Override
 			public Long apply(File file) {
 				return file.length();
 			}
 		},
 		LAST_MODIFIED {
 			@Override
 			public Long apply(File file) {
 				return file.lastModified();
 			}
 		},
 		TOTAL_SPACE {
 			@Override
 			public Long apply(File file) {
 				return file.getTotalSpace();
 			}
 		},
 		USABLE_SPACE {
 			@Override
 			public Long apply(File file) {
 				return file.getUsableSpace();
 			}
 		},
 		FREE_SPACE {
 			@Override
 			public Long apply(File file) {
 				return file.getFreeSpace();
 			}
 		}
 	}
 
 }