/*

  * 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.ArrayList;

 import java.util.Collections;

 import java.util.Comparator;

 import java.util.HashSet;

 import java.util.Iterator;

 import java.util.List;

 import java.util.ListIterator;

 import java.util.Set;

 import org.apache.commons.cli2.Argument;

 import org.apache.commons.cli2.DisplaySetting;

 import org.apache.commons.cli2.Group;

 import org.apache.commons.cli2.OptionException;

 import org.apache.commons.cli2.WriteableCommandLine;

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

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

 /**

  * Represents a cvs "update" style command line option.

  *

  * Like all Parents, Commands can have child options and can be part of

  * Arguments

  */

 public class Command

     extends ParentImpl {

     /** The display name for the command */

     private final String preferredName;

     /** The aliases for this command */

     private final Set aliases;

     /** All the names for this command */

     private final Set triggers;

     /**

      * Creates a new Command instance.

      *

      * @param preferredName

      *            The name normally used to refer to the Command

      * @param description

      *            A description of the Command

      * @param aliases

      *            Alternative names for the Command

      * @param required

      *            Whether the Command is required

      * @param argument

      *            An Argument that the command takes

      * @param children

      *            The Group of child options for this Command

      * @param id

      *            A unique id for the Command

      *

      * @see ParentImpl#ParentImpl(Argument, Group, String, int, boolean)

      */

     public Command(final String preferredName,

                    final String description,

                    final Set aliases,

                    final boolean required,

                    final Argument argument,

                    final Group children,

                    final int id) {

         super(argument, children, description, id, required);

         // check the preferred name is valid

         if ((preferredName == null) || (preferredName.length() < 1)) {

             throw new IllegalArgumentException(ResourceHelper.getResourceHelper().getMessage(ResourceConstants.COMMAND_PREFERRED_NAME_TOO_SHORT));

         }

         this.preferredName = preferredName;

         // gracefully and defensively handle aliases

         this.aliases =

             (aliases == null) ? Collections.EMPTY_SET

                               : Collections.unmodifiableSet(new HashSet(aliases));

         // populate the triggers Set

         final Set newTriggers = new HashSet();

         newTriggers.add(preferredName);

         newTriggers.addAll(this.aliases);

         this.triggers = Collections.unmodifiableSet(newTriggers);

     }

     public void processParent(final WriteableCommandLine commandLine,

                               final ListIterator arguments)

         throws OptionException {

         // grab the argument to process

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

         // if we can process it

         if (canProcess(commandLine, arg)) {

             // then note the option

             commandLine.addOption(this);

             // normalise the argument list

             arguments.set(preferredName);

         } else {

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

         }

     }

     public Set getTriggers() {

         return triggers;

     }

     public void validate(WriteableCommandLine commandLine)

         throws OptionException {

         if (isRequired() && !commandLine.hasOption(this)) {

             throw new OptionException(this, ResourceConstants.OPTION_MISSING_REQUIRED,

                                       getPreferredName());

         }

         super.validate(commandLine);

     }

     public void appendUsage(final StringBuffer buffer,

                             final Set helpSettings,

                             final Comparator comp) {

         // do we display optionality

         final boolean optional =

             !isRequired() && helpSettings.contains(DisplaySetting.DISPLAY_OPTIONAL);

         final boolean displayAliases = helpSettings.contains(DisplaySetting.DISPLAY_ALIASES);

         if (optional) {

             buffer.append('[');

         }

         buffer.append(preferredName);

         if (displayAliases && !aliases.isEmpty()) {

             buffer.append(" (");

             final List list = new ArrayList(aliases);

             Collections.sort(list);

             for (final Iterator i = list.iterator(); i.hasNext();) {

                 final String alias = (String) i.next();

                 buffer.append(alias);

                 if (i.hasNext()) {

                     buffer.append(',');

                 }

             }

             buffer.append(')');

         }

         super.appendUsage(buffer, helpSettings, comp);

         if (optional) {

             buffer.append(']');

         }

     }

     public String getPreferredName() {

         return preferredName;

     }

 }