/*

  * 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.

  */

 package org.apache.commons.cli2.option;

 import java.util.Collections;

 import java.util.Comparator;

 import java.util.List;

 import java.util.ListIterator;

 import java.util.Set;

 import org.apache.commons.cli2.DisplaySetting;

 import org.apache.commons.cli2.HelpLine;

 import org.apache.commons.cli2.OptionException;

 import org.apache.commons.cli2.WriteableCommandLine;

 import org.apache.commons.cli2.resource.ResourceConstants;

 /**

  * Handles the java style "-Dprop=value" opions

  */

 public class PropertyOption

     extends OptionImpl {

     public static final String DEFAULT_OPTION_STRING = "-D";

     public static final String DEFAULT_DESCRIPTION =

         "Passes properties and values to the application";

     /**

      * A default PropertyOption instance

      */

     public static final PropertyOption INSTANCE = new PropertyOption();

     private final String optionString;

     private final String description;

     private final Set prefixes;

     /**

      * Creates a new PropertyOption using the default settings of a "-D" trigger

      * and an id of 'D'

      */

     public PropertyOption() {

         this(DEFAULT_OPTION_STRING, DEFAULT_DESCRIPTION, 'D');

     }

     /**

      * Creates a new PropertyOption using the specified parameters

      * @param optionString the trigger for the Option

      * @param description the description of the Option

      * @param id the id of the Option

      */

     public PropertyOption(final String optionString,

                           final String description,

                           final int id) {

         super(id, false);

         this.optionString = optionString;

         this.description = description;

         this.prefixes = Collections.singleton(optionString);

     }

     public boolean canProcess(final WriteableCommandLine commandLine,

                               final String argument) {

         return (argument != null) && argument.startsWith(optionString) &&

                (argument.length() > optionString.length());

     }

     public Set getPrefixes() {

         return prefixes;

     }

     public void process(final WriteableCommandLine commandLine,

                         final ListIterator arguments)

         throws OptionException {

         final String arg = (String) arguments.next();

         if (!canProcess(commandLine, arg)) {

             throw new OptionException(this, ResourceConstants.UNEXPECTED_TOKEN, arg);

         }

         final int propertyStart = optionString.length();

         final int equalsIndex = arg.indexOf('=', propertyStart);

         final String property;

         final String value;

         if (equalsIndex < 0) {

             property = arg.substring(propertyStart);

             value = "true";

         } else {

             property = arg.substring(propertyStart, equalsIndex);

             value = arg.substring(equalsIndex + 1);

         }

         commandLine.addProperty(this, property, value);

     }

     public Set getTriggers() {

         return Collections.singleton(optionString);

     }

     public void validate(WriteableCommandLine commandLine) {

         // PropertyOption needs no validation

     }

     public void appendUsage(final StringBuffer buffer,

                             final Set helpSettings,

                             final Comparator comp) {

         final boolean display = helpSettings.contains(DisplaySetting.DISPLAY_PROPERTY_OPTION);

         final boolean bracketed = helpSettings.contains(DisplaySetting.DISPLAY_ARGUMENT_BRACKETED);

         if (display) {

             buffer.append(optionString);

             if (bracketed) {

                 buffer.append('<');

             }

             buffer.append("property");

             if (bracketed) {

                 buffer.append('>');

             }

             buffer.append("=");

             if (bracketed) {

                 buffer.append('<');

             }

             buffer.append("value");

             if (bracketed) {

                 buffer.append('>');

             }

         }

     }

     public String getPreferredName() {

         return optionString;

     }

     public String getDescription() {

         return description;

     }

     public List helpLines(final int depth,

                           final Set helpSettings,

                           final Comparator comp) {

         if (helpSettings.contains(DisplaySetting.DISPLAY_PROPERTY_OPTION)) {

             final HelpLine helpLine = new HelpLineImpl(this, depth);

             return Collections.singletonList(helpLine);

         } else {

             return Collections.EMPTY_LIST;

         }

     }

 }