/**
    *	jline - Java console input library
    *	Copyright (c) 2002, 2003, 2004, 2005, Marc Prud'hommeaux <mwp1@cornell.edu>
    *	All rights reserved.
    *
    *	Redistribution and use in source and binary forms, with or
    *	without modification, are permitted provided that the following
    *	conditions are met:
    *
   *	Redistributions of source code must retain the above copyright
   *	notice, this list of conditions and the following disclaimer.
   *
   *	Redistributions in binary form must reproduce the above copyright
   *	notice, this list of conditions and the following disclaimer
   *	in the documentation and/or other materials provided with
   *	the distribution.
   *
   *	Neither the name of JLine nor the names of its contributors
   *	may be used to endorse or promote products derived from this
   *	software without specific prior written permission.
   *
   *	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   *	"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
   *	BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
   *	AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
   *	EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
   *	FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
   *	OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   *	PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   *	DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   *	AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   *	LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   *	IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   *	OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package jline;
  
  import java.io.*;
  import java.util.*;
  
  
  /**
   *  A file name completor takes the buffer and issues a list of
   *  potential completions.
   *
   *	<p>
   *	This completor tries to behave as similar as possible to
   *	<i>bash</i>'s file name completion (using GNU readline)
   *	with the following exceptions:
   *
   *	<ul>
   *	<li>Candidates that are directories will end with "/"</li>
   *	<li>Wildcard regular expressions are not evaluated or replaced</li>
   *	<li>The "~" character can be used to represent the user's home,
   *		but it cannot complete to other users' homes, since java does
   *		not provide any way of determining that easily</li>
   *	</ul>
   *
   *	<p>TODO</p>
   *	<ul>
   *	<li>Handle files with spaces in them</li>
   *	<li>Have an option for file type color highlighting</li>
   *	</ul>
   *
   *  @author  <a href="mailto:mwp1@cornell.edu">Marc Prud'hommeaux</a>
   */
  public class FileNameCompletor
  	implements Completor
  {
  	public int complete (final String buf, final int cursor,
  		final List candidates)
  	{
  		String buffer = buf == null ? "" : buf;
  
  		String translated = buffer;
  
  		// special character: ~ maps to the user's home directory
  		if (translated.startsWith ("~" + File.separator))
  		{
  			translated = System.getProperty ("user.home")
  				+ translated.substring (1);
  		}
  		else if (translated.startsWith ("~"))
  		{
  			translated = new File (System.getProperty ("user.home"))
  				.getParentFile ().getAbsolutePath ();
  		}
  		else if (!(translated.startsWith (File.separator)))
  		{
  			translated = new File ("").getAbsolutePath ()
  				+ File.separator + translated;
  		}
  
  		File f = new File (translated);
  
  		final File dir;
  		
  		if (translated.endsWith (File.separator))
  			dir = f;
 		else
 			dir = f.getParentFile ();
 		
 		final File [] entries = dir == null ? new File [0] : dir.listFiles ();
 
 		try
 		{
 			return matchFiles (buffer, translated, entries, candidates);
 		}
 		finally
 		{
 			// we want to output a sorted list of files
 			sortFileNames (candidates);
 		}
 	}
 
 
 	protected void sortFileNames (final List fileNames)
 	{
 		Collections.sort (fileNames);
 	}
 
 
 	/**
 	 *  Match the specified <i>buffer</i> to the array of <i>entries</i>
 	 *  and enter the matches into the list of <i>candidates</i>. This method
 	 *  can be overridden in a subclass that wants to do more
 	 *  sophisticated file name completion.
 	 *
 	 *  @param	buffer		the untranslated buffer	
 	 *  @param	translated	the buffer with common characters replaced	
 	 *  @param	entries		the list of files to match	
 	 *  @param	candidates	the list of candidates to populate	
 	 *
 	 *  @return  the offset of the match
 	 */
 	public int matchFiles (String buffer, String translated,
 		File [] entries, List candidates)
 	{
 		if (entries == null)
 			return -1;
 
 		int matches = 0;
 
 		// first pass: just count the matches
 		for (int i = 0; i < entries.length; i++)
 		{
 			if (entries [i].getAbsolutePath ().startsWith (translated))
 			{
 				matches++;
 			}
 		}
 
 		// green - executable
 		// blue - directory
 		// red - compressed
 		// cyan - symlink
 		for (int i = 0; i < entries.length; i++)
 		{
 			if (entries [i].getAbsolutePath ().startsWith (translated))
 			{
 				String name = entries [i].getName ()
 					+ (matches == 1 && entries [i].isDirectory ()
 						? File.separator : " ");
 
 				/*
 				if (entries [i].isDirectory ())
 				{
 					name = new ANSIBuffer ().blue (name).toString ();
 				}
 				*/
 
 				candidates.add (name);
 			}
 		}
 
 
 		final int index = buffer.lastIndexOf (File.separator);
 		return index + File.separator.length ();
 	}
 }