/*

     dsh-commandline  Command line parser based on typed arguments.

     Copyright (c) 2004-2012 held jointly by the individual authors.

     This library is free software; you can redistribute it and/or modify it

     under the terms of the GNU Lesser General Public License as published

     by the Free Software Foundation; either version 3 of the License, or (at

     your option) any later version.

     This library is distributed in the hope that it will be useful, but WITHOUT

     ANY WARRANTY; with out even the implied warranty of MERCHANTABILITY or

     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public

     License for more details.

     You should have received a copy of the GNU Lesser General Public License

     along with this library;  if not, write to the Free Software Foundation,

     Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA.

     > http://www.fsf.org/licensing/licenses/lgpl.html

     > http://www.opensource.org/licenses/lgpl-license.php

 */

 package org.dishevelled.commandline;

 import java.io.PrintWriter;

 import java.io.OutputStream;

 import java.util.Arrays;

 import java.lang.reflect.ParameterizedType;

 import java.lang.reflect.Type;

 /**

  * Usage string.

  *

  * @author  Michael Heuer

  * @version $Revision: 1059 $ $Date: 2012-01-03 14:03:02 -0600 (Tue, 03 Jan 2012) $

  */

 public final class Usage

 {

     /**

      * Private no-arg constructor.

      */

     private Usage()

     {

         // empty

     }

     /**

      * Generate an usage string to the specified output stream.

      *

      * @param message message

      * @param cause cause

      * @param commandLine command line

      * @param arguments list of arguments

      * @param out output stream, must not be null

      */

     public static void usage(final String message,

                              final Throwable cause,

                              final CommandLine commandLine,

                              final ArgumentList arguments,

                              final OutputStream out)

     {

         if (out == null)

         {

             throw new IllegalArgumentException("out must not be null");

         }

         PrintWriter pw = new PrintWriter(out, false);

         pw.println("usage:");

         if (message != null)

         {

             pw.println(message);

             pw.print("\n");

         }

         if (cause != null)

         {

             cause.printStackTrace(pw);

             pw.print("\n");

         }

         if ((arguments != null) && (arguments.size() > 0))

         {

             pw.println("arguments:");

             for (Argument<?> a : arguments)

             {

                 StringBuffer sb = new StringBuffer();

                 sb.append("   -");

                 sb.append(a.getShortName());

                 sb.append(", --");

                 sb.append(a.getLongName());

                 if (!(a instanceof Switch))

                 {

                     sb.append(" ");

                     ParameterizedType parameterizedType = (ParameterizedType) a.getClass().getGenericSuperclass();

                     Type[] types = parameterizedType.getActualTypeArguments();

                     sb.append(Arrays.asList(types));

                 }

                 sb.append("  ");

                 sb.append(a.getDescription());

                 if (a.isRequired())

                 {

                     sb.append(" [required]");

                 }

                 else

                 {

                     sb.append(" [optional]");

                 }

                 pw.println(sb.toString());

                 pw.print("\n");

             }

         }

         pw.flush();

     }

 }