package org.apache.archiva.checksum;
   
   /*
    * 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 java.io.File;
  
  import org.apache.commons.io.FilenameUtils;
  
  /**
   * Enumeration of available ChecksumAlgorithm techniques.
   *
   *
   */
  public enum ChecksumAlgorithm {
      SHA1("SHA-1", "sha1", "SHA1"),
      MD5("MD5", "md5", "MD5");
  
      public static ChecksumAlgorithm getByExtension( File file )
      {
          String ext = FilenameUtils.getExtension( file.getName() ).toLowerCase();
          if ( ChecksumAlgorithm.SHA1.getExt().equals( ext ) )
          {
              return ChecksumAlgorithm.SHA1;
          }
          else if ( ChecksumAlgorithm.MD5.getExt().equals( ext ) )
          {
              return ChecksumAlgorithm.MD5;
          }
  
          throw new IllegalArgumentException( "Filename " + file.getName() + " has no associated extension." );
      }
  
      /**
       * The MessageDigest algorithm for this hash.
       */
      private final String algorithm;
  
      /**
       * The file extension for this ChecksumAlgorithm.
       */
      private final String ext;
  
      /**
       * The checksum type, the key that you see in checksum files.
       */
      private final String type;
  
      /**
       * Construct a ChecksumAlgorithm
       * 
       * @param algorithm the MessageDigest algorithm
       * @param ext the file extension.
       * @param type the checksum type.
       */
      private ChecksumAlgorithm( String algorithm, String ext, String type )
      {
          this.algorithm = algorithm;
          this.ext = ext;
          this.type = type;
      }
  
      public String getAlgorithm()
      {
          return algorithm;
      }
  
      public String getExt()
      {
          return ext;
      }
  
      public String getType()
      {
          return type;
      }
      
      
  }