/*
    * 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.commons.net.tftp;
  
  import java.io.BufferedInputStream;
  import java.io.BufferedOutputStream;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  
  import org.apache.commons.net.tftp.TFTPServer.ServerMode;
  
  import junit.framework.TestCase;
  
  /**
   * Test the TFTP Server and TFTP Client by creating some files in the system temp folder and then
   * uploading and downloading them.
   */
  public class TFTPTest extends TestCase
  {
      private static final int SERVER_PORT = 6902;
      private static TFTPServer tftpS;
      private static final File serverDirectory = new File(System.getProperty("java.io.tmpdir"));
      private static final String filePrefix = "tftp-";
      private static final File[] files = new File[8];
  
      static int testsLeftToRun = 6;
  
      // only want to do this once...
      static
      {
          try
          {
              files[0] = createFile(new File(serverDirectory, filePrefix + "empty.txt"), 0);
              files[1] = createFile(new File(serverDirectory, filePrefix + "small.txt"), 1);
              files[2] = createFile(new File(serverDirectory, filePrefix + "511.txt"), 511);
              files[3] = createFile(new File(serverDirectory, filePrefix + "512.txt"), 512);
              files[4] = createFile(new File(serverDirectory, filePrefix + "513.txt"), 513);
              files[5] = createFile(new File(serverDirectory, filePrefix + "med.txt"), 1000 * 1024);
              files[6] = createFile(new File(serverDirectory, filePrefix + "big.txt"), 5000 * 1024);
              files[7] = createFile(new File(serverDirectory, filePrefix + "huge.txt"), 37000 * 1024);
  
              // Start the server
              tftpS = new TFTPServer(serverDirectory, serverDirectory, SERVER_PORT, ServerMode.GET_AND_PUT,
                      null, null);
              tftpS.setSocketTimeout(2000);
          }
          catch (IOException e)
          {
              e.printStackTrace();
          }
  
      }
  
      @Override
      protected void tearDown() throws Exception
      {
          testsLeftToRun--;
          if (testsLeftToRun <= 0)
          {
              if (tftpS != null)
              {
                  tftpS.shutdown();
              }
              for (File file : files)
              {
                  file.delete();
              }
          }
          super.tearDown();
      }
  
      /*
       * Create a file, size specified in bytes
       */
      private static File createFile(File file, int size) throws IOException
      {
          OutputStream os = new BufferedOutputStream(new FileOutputStream(file));
          byte[] temp = "0".getBytes();
          for (int i = 0; i < size; i++)
          {
              os.write(temp);
         }
         os.close();
         return file;
     }
 
     public void testTFTPBinaryDownloads() throws Exception
     {
         // test with the smaller files
         for (int i = 0; i < 6; i++)
         {
             testDownload(TFTP.BINARY_MODE, files[i]);
         }
     }
 
     public void testASCIIDownloads() throws Exception
     {
         // test with the smaller files
         for (int i = 0; i < 6; i++)
         {
             try {
                 testDownload(TFTP.ASCII_MODE, files[i]);
             } catch (IOException e) {
                 fail("Entry "+i+" Error "+e.toString());
             }
 
         }
     }
 
     public void testTFTPBinaryUploads() throws Exception
     {
         // test with the smaller files
         for (int i = 0; i < 6; i++)
         {
             testUpload(TFTP.BINARY_MODE, files[i]);
         }
     }
 
     public void testASCIIUploads() throws Exception
     {
         // test with the smaller files
         for (int i = 0; i < 6; i++)
         {
             testUpload(TFTP.ASCII_MODE, files[i]);
         }
     }
 
     public void testHugeUploads() throws Exception
     {
         for (int i = 5; i < files.length; i++)
         {
             testUpload(TFTP.BINARY_MODE, files[i]);
         }
     }
 
     public void testHugeDownloads() throws Exception
     {
         // test with the smaller files
         for (int i = 5; i < files.length; i++)
         {
             testDownload(TFTP.BINARY_MODE, files[i]);
         }
     }
 
     private void testDownload(int mode, File file) throws IOException
     {
         // Create our TFTP instance to handle the file transfer.
         TFTPClient tftp = new TFTPClient();
         tftp.open();
         tftp.setSoTimeout(2000);
 
         File out = new File(serverDirectory, filePrefix + "download");
 
         // cleanup old failed runs
         out.delete();
         assertTrue("Couldn't clear output location", !out.exists());
 
         FileOutputStream output = new FileOutputStream(out);
 
         tftp.receiveFile(file.getName(), mode, output, "localhost", SERVER_PORT);
         output.close();
 
         assertTrue("file not created", out.exists());
         assertTrue("files not identical on file " + file, filesIdentical(out, file));
 
         // delete the downloaded file
         out.delete();
     }
 
     private void testUpload(int mode, File file) throws Exception
     {
         // Create our TFTP instance to handle the file transfer.
         TFTPClient tftp = new TFTPClient();
         tftp.open();
         tftp.setSoTimeout(2000);
 
         File in = new File(serverDirectory, filePrefix + "upload");
         // cleanup old failed runs
         in.delete();
         assertTrue("Couldn't clear output location", !in.exists());
 
         FileInputStream fis = new FileInputStream(file);
         tftp.sendFile(in.getName(), mode, fis, "localhost", SERVER_PORT);
         fis.close();
 
         // need to give the server a bit of time to receive our last packet, and
         // close out its file buffers, etc.
         Thread.sleep(100);
         assertTrue("file not created", in.exists());
         assertTrue("files not identical on file " + file, filesIdentical(file, in));
 
         in.delete();
     }
 
     private boolean filesIdentical(File a, File b) throws IOException
     {
         if (!a.exists() || !b.exists())
         {
             return false;
         }
 
         if (a.length() != b.length())
         {
             return false;
         }
 
         InputStream fisA = new BufferedInputStream(new FileInputStream(a));
         InputStream fisB = new BufferedInputStream(new FileInputStream(b));
 
         int aBit = fisA.read();
         int bBit = fisB.read();
 
         while (aBit != -1)
         {
             if (aBit != bBit)
             {
                 fisA.close();
                 fisB.close();
                 return false;
             }
             aBit = fisA.read();
             bBit = fisB.read();
         }
 
         fisA.close();
         fisB.close();
         return true;
     }
 }