//
   //  ========================================================================
   //  Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.start;
  
  import java.io.File;
  import java.util.ArrayList;
  import java.util.List;
  
  public class CommandLineBuilder
  {
      public static File findExecutable(File root, String path)
      {
          String npath = path.replace('/',File.separatorChar);
          File exe = new File(root,npath);
          if (!exe.exists())
          {
              return null;
          }
          return exe;
      }
  
      public static String findJavaBin()
      {
          File javaHome = new File(System.getProperty("java.home"));
          if (!javaHome.exists())
          {
              return null;
          }
  
          File javabin = findExecutable(javaHome,"bin/java");
          if (javabin != null)
          {
              return javabin.getAbsolutePath();
          }
  
          javabin = findExecutable(javaHome,"bin/java.exe");
          if (javabin != null)
          {
              return javabin.getAbsolutePath();
          }
  
          return "java";
      }
  
      /**
       * Perform an optional quoting of the argument, being intelligent with spaces and quotes as needed. If a subString is set in quotes it won't the subString
       * won't be escaped.
       * 
       * @param arg
       * @return
       */
      public static String quote(String arg)
      {
          boolean needsQuoting = (arg.indexOf(' ') >= 0) || (arg.indexOf('"') >= 0);
          if (!needsQuoting)
          {
              return arg;
          }
          StringBuilder buf = new StringBuilder();
          // buf.append('"');
          boolean escaped = false;
          boolean quoted = false;
          for (char c : arg.toCharArray())
          {
              if (!quoted && !escaped && ((c == '"') || (c == ' ')))
              {
                  buf.append("\\");
              }
              // don't quote text in single quotes
              if (!escaped && (c == '\''))
              {
                  quoted = !quoted;
              }
              escaped = (c == '\\');
              buf.append(c);
          }
          // buf.append('"');
          return buf.toString();
      }
  
      private List<String> args;
  
      public CommandLineBuilder()
     {
         args = new ArrayList<String>();
     }
 
     public CommandLineBuilder(String bin)
     {
         this();
         args.add(bin);
     }
 
     /**
      * Add a simple argument to the command line.
      * <p>
      * Will quote arguments that have a space in them.
      * 
      * @param arg
      *            the simple argument to add
      */
     public void addArg(String arg)
     {
         if (arg != null)
         {
             args.add(quote(arg));
         }
     }
 
     /**
      * Similar to {@link #addArg(String)} but concats both name + value with an "=" sign, quoting were needed, and excluding the "=" portion if the value is
      * undefined or empty.
      * <p>
      * 
      * <pre>
      *   addEqualsArg("-Dname", "value") = "-Dname=value"
      *   addEqualsArg("-Djetty.home", "/opt/company inc/jetty (7)/") = "-Djetty.home=/opt/company\ inc/jetty\ (7)/"
      *   addEqualsArg("-Djenkins.workspace", "/opt/workspaces/jetty jdk7/") = "-Djenkins.workspace=/opt/workspaces/jetty\ jdk7/"
      *   addEqualsArg("-Dstress", null) = "-Dstress"
      *   addEqualsArg("-Dstress", "") = "-Dstress"
      * </pre>
      * 
      * @param name
      *            the name
      * @param value
      *            the value
      */
     public void addEqualsArg(String name, String value)
     {
         if ((value != null) && (value.length() > 0))
         {
             args.add(quote(name + "=" + value));
         }
         else
         {
             args.add(quote(name));
         }
     }
 
     /**
      * Add a simple argument to the command line.
      * <p>
      * Will <b>NOT</b> quote/escape arguments that have a space in them.
      * 
      * @param arg
      *            the simple argument to add
      */
     public void addRawArg(String arg)
     {
         if (arg != null)
         {
             args.add(arg);
         }
     }
 
     public List<String> getArgs()
     {
         return args;
     }
 
     @Override
     public String toString()
     {
         StringBuilder buf = new StringBuilder();
 
         boolean delim = false;
         for (String arg : args)
         {
             if (delim)
             {
                 buf.append(' ');
             }
             buf.append(quote(arg));
             delim = true;
         }
 
         return buf.toString();
     }
 }