package org.apache.maven.archetype.common.util;
   
   /*
    * 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.
   */
  
  import org.codehaus.plexus.logging.AbstractLogEnabled;
  import org.mozilla.intl.chardet.nsDetector;
  import org.mozilla.intl.chardet.nsICharsetDetectionObserver;
  import org.mozilla.intl.chardet.nsPSMDetector;
  
  import java.io.BufferedInputStream;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.InputStream;
  
  /** @author rafale */
  public class FileCharsetDetector
      extends AbstractLogEnabled
  {
      private String charset = null;
  
      private boolean found = false;
  
      public FileCharsetDetector( File detectedFile )
          throws FileNotFoundException, IOException
      {
          nsDetector det = new nsDetector( nsPSMDetector.ALL );
  
          det.Init(
              new nsICharsetDetectionObserver()
              {
                  public void Notify( String charset )
                  {
                      FileCharsetDetector.this.charset = charset;
                      FileCharsetDetector.this.found = true;
                  }
              }
          );
  
          BufferedInputStream imp = new BufferedInputStream( new FileInputStream( detectedFile ) );
  
          byte[] buf = new byte[1024];
          int len;
          boolean done = false;
          boolean isAscii = true;
  
          while ( ( len = imp.read( buf, 0, buf.length ) ) != -1 )
          {
              // Check if the stream is only ascii.
              if ( isAscii )
              {
                  isAscii = det.isAscii( buf, len );
              }
  
              // DoIt if non-ascii and not done yet.
              if ( !isAscii && !done )
              {
                  done = det.DoIt( buf, len, false );
                  found = done;
              }
          }
          det.DataEnd();
  
          if ( !isFound() )
          {
              String[] prob = det.getProbableCharsets();
  
              if ( prob.length > 0 )
              {
                  charset = prob[0];
              }
          }
  
          if ( isAscii )
          {
              charset = "ASCII";
          }
      }
  
      public FileCharsetDetector( InputStream detectedStream )
          throws FileNotFoundException, IOException
     {
         nsDetector det = new nsDetector( nsPSMDetector.ALL );
 
         det.Init(
             new nsICharsetDetectionObserver()
             {
                 public void Notify( String charset )
                 {
                     FileCharsetDetector.this.charset = charset;
                     FileCharsetDetector.this.found = true;
                 }
             }
         );
 
         BufferedInputStream imp = new BufferedInputStream( detectedStream );
 
         byte[] buf = new byte[1024];
         int len;
         boolean done = false;
         boolean isAscii = true;
 
         while ( ( len = imp.read( buf, 0, buf.length ) ) != -1 )
         {
             // Check if the stream is only ascii.
             if ( isAscii )
             {
                 isAscii = det.isAscii( buf, len );
             }
 
             // DoIt if non-ascii and not done yet.
             if ( !isAscii && !done )
             {
                 done = det.DoIt( buf, len, false );
                 found = done;
             }
         }
         det.DataEnd();
 
         if ( !isFound() )
         {
             String[] prob = det.getProbableCharsets();
 
             if ( prob.length > 0 )
             {
                 charset = prob[0];
             }
         }
 
         if ( isAscii )
         {
             charset = "ASCII";
         }
     }
 
     public String getCharset()
     {
         return charset;
     }
 
     public boolean isFound()
     {
         return found;
     }
 }