content: /*
   * 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.bookkeeper.tools.framework;
  
  /**
   * Help command to show help information.
   */
  class HelpCommand<GlobalFlagsT extends CliFlags, CommandFlagsT extends CliFlags>
          implements Command<GlobalFlagsT> {
  
      private final Cli<CommandFlagsT> cli;
  
      HelpCommand(Cli<CommandFlagsT> cli) {
          this.cli = cli;
      }
  
      @Override
      public String name() {
          return "help";
      }
  
      @Override
      public String description() {
          return "Display help information about it";
      }
  
      @Override
      public Boolean apply(GlobalFlagsT globalFlags, String[] args) throws Exception {
          if (args.length == 0) {
              cli.usage();
              return true;
          }
  
          String cmd = args[0];
          Command command = cli.getCommand(cmd);
          if (null != command) {
              command.usage();
          } else {
              cli.usage("Command \"" + cmd + "\" is not found.");
          }
  
          return true;
      }
  
      @Override
      public void usage() {
          cli.console("Help provides help for any command in this cli.");
          cli.console("Simply type '" + cli.cmdPath() + " help [command]' for full details.");
          cli.console("");
          CommandUtils.printUsage(cli.console(), cli.cmdPath() + " help [command] [options]");
      }
  
  }
  