<?php

/*

 * This file is part of the Symfony package.

 *

 * (c) Fabien Potencier <fabien@symfony.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Symfony\Component\Console\Command;

use Symfony\Component\Console\Input\InputArgument;

use Symfony\Component\Console\Input\InputOption;

use Symfony\Component\Console\Input\InputInterface;

use Symfony\Component\Console\Output\OutputInterface;

use Symfony\Component\Console\Output\Output;

use Symfony\Component\Console\Command\Command;

/**

 * HelpCommand displays the help for a given command.

 *

 * @author Fabien Potencier <fabien@symfony.com>

 */

class HelpCommand extends Command

{

    private $command;

    /**

     * {@inheritdoc}

     */

    protected function configure()

    {

        $this->ignoreValidationErrors = true;

        $this

            ->setDefinition(array(

                new InputArgument('command_name', InputArgument::OPTIONAL, 'The command name', 'help'),

                new InputOption('xml', null, InputOption::VALUE_NONE, 'To output help as XML'),

            ))

            ->setName('help')

            ->setDescription('Displays help for a command')

            ->setHelp(<<<EOF

The <info>help</info> command displays help for a given command:

  <info>php app/console help list</info>

You can also output the help as XML by using the <comment>--xml</comment> option:

  <info>php app/console help --xml list</info>

EOF

            );

    }

    /**

     * Sets the command

     *

     * @param Command $command The command to set

     */

    public function setCommand(Command $command)

    {

        $this->command = $command;

    }

    /**

     * {@inheritdoc}

     */

    protected function execute(InputInterface $input, OutputInterface $output)

    {

        if (null === $this->command) {

            $this->command = $this->getApplication()->get($input->getArgument('command_name'));

        }

        if ($input->getOption('xml')) {

            $output->writeln($this->command->asXml(), OutputInterface::OUTPUT_RAW);

        } else {

            $output->writeln($this->command->asText());

        }

    }

}