package org.apache.archiva.common.utils;
   
   /*
    * 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.apache.commons.lang.StringUtils;
  
  import java.io.File;
  import java.net.MalformedURLException;
  
  /**
   * PathUtil - simple utility methods for path manipulation.
   *
   *
   */
  public class PathUtil
  {
      public static String toUrl( String path )
      {
          // Is our work already done for us?
          if ( path.startsWith( "file:/" ) )
          {
              return path;
          }
  
          return toUrl( new File( path ) );
      }
  
      public static String toUrl( File file )
      {
          try
          {
              return file.toURI().toURL().toExternalForm();
          }
          catch ( MalformedURLException e )
          {
              String pathCorrected = StringUtils.replaceChars( file.getAbsolutePath(), '\\', '/' );
              if ( pathCorrected.startsWith( "file:/" ) )
              {
                  return pathCorrected;
              }
  
              return "file://" + pathCorrected;
          }
      }
  
      /**
       * Given a basedir and a child file, return the relative path to the child.
       *
       * @param basedir the basedir.
       * @param file    the file to get the relative path for.
       * @return the relative path to the child. (NOTE: this path will NOT start with a {@link File#separator} character)
       */
      public static String getRelative( String basedir, File file )
      {
          return getRelative( basedir, file.getAbsolutePath() );
      }
  
      /**
       * Given a basedir and a child file, return the relative path to the child.
       *
       * @param basedir the basedir.
       * @param child   the child path (can be a full path)
       * @return the relative path to the child. (NOTE: this path will NOT start with a {@link File#separator} character)
       */
      public static String getRelative( String basedir, String child )
      {
          if ( basedir.endsWith( "/" ) || basedir.endsWith( "\\" ) )
          {
              basedir = basedir.substring( 0, basedir.length() - 1 );
          }
  
          if ( child.startsWith( basedir ) )
          {
              // simple solution.
              return child.substring( basedir.length() + 1 );
          }
  
          String absoluteBasedir = new File( basedir ).getAbsolutePath();
          if ( child.startsWith( absoluteBasedir ) )
          {
              // resolved basedir solution.
              return child.substring( absoluteBasedir.length() + 1 );
         }
 
         // File is not within basedir.
         throw new IllegalStateException(
             "Unable to obtain relative path of file " + child + ", it is not within basedir " + basedir + "." );
     }
 }