/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.hadoop.fs;

import org.apache.hadoop.conf.Configuration;
import java.io.*;
import junit.framework.*;

/**
 * This class tests the local file system via the FileSystem abstraction.
 * @author Owen O'Malley
 */
public class TestLocalFileSystem extends TestCase {

  private void writeFile(FileSystem fs, Path name) throws IOException {
    FSDataOutputStream stm = fs.create(name);
    stm.writeBytes("42\n");
    stm.close();
  }
  
  private void cleanupFile(FileSystem fs, Path name) throws IOException {
    assertTrue(fs.exists(name));
    fs.delete(name);
    assertTrue(!fs.exists(name));
  }
  
  /**
   * Test the capability of setting the working directory.
   */
  public void testWorkingDirectory() throws IOException {
    Configuration conf = new Configuration();
    FileSystem fileSys = FileSystem.getLocal(conf);
    Path origDir = fileSys.getWorkingDirectory();
    Path subdir = new Path("build/test/data/work-dir/new subdir");
    try {
      // make sure it doesn't already exist
      assertTrue(!fileSys.exists(subdir));
      // make it and check for it
      assertTrue(fileSys.mkdirs(subdir));
      assertTrue(fileSys.isDirectory(subdir));
      
      fileSys.setWorkingDirectory(subdir);
      
      // create a directory and check for it
      Path dir1 = new Path("dir1");
      assertTrue(fileSys.mkdirs(dir1));
      assertTrue(fileSys.isDirectory(dir1));
      
      // delete the directory and make sure it went away
      fileSys.delete(dir1);
      assertTrue(!fileSys.exists(dir1));
      
      // create files and manipulate them.
      Path file1 = new Path("file1");
      Path file2 = new Path("sub/file2");
      writeFile(fileSys, file1);
      fileSys.copyFromLocalFile(file1, file2);
      assertTrue(fileSys.exists(file1));
      assertTrue(fileSys.isFile(file1));
      cleanupFile(fileSys, file2);
      fileSys.copyToLocalFile(file1, file2);
      cleanupFile(fileSys, file2);
      
      // try a rename
      fileSys.rename(file1, file2);
      assertTrue(!fileSys.exists(file1));
      assertTrue(fileSys.exists(file2));
      fileSys.rename(file2, file1);
      
      // try reading a file
      InputStream stm = fileSys.open(file1);
      byte[] buffer = new byte[3];
      int bytesRead = stm.read(buffer, 0, 3);
      assertEquals("42\n", new String(buffer, 0, bytesRead));
      stm.close();
    } finally {
      fileSys.setWorkingDirectory(origDir);
      fileSys.delete(subdir);
    }
  }
}
