1: <?php
  2: 
  3: /*
  4:  * This file is part of the Symfony package.
  5:  *
  6:  * (c) Fabien Potencier <fabien@symfony.com>
  7:  *
  8:  * For the full copyright and license information, please view the LICENSE
  9:  * file that was distributed with this source code.
 10:  */
 11: 
 12: namespace Symfony\Component\Console\Helper;
 13: 
 14: use Symfony\Component\Console\Output\OutputInterface;
 15: 
 16: /**
 17:  * The Dialog class provides helpers to interact with the user.
 18:  *
 19:  * @author Fabien Potencier <fabien@symfony.com>
 20:  */
 21: class DialogHelper extends Helper
 22: {
 23:     private $inputStream;
 24: 
 25:     /**
 26:      * Asks a question to the user.
 27:      *
 28:      * @param OutputInterface $output   An Output instance
 29:      * @param string|array    $question The question to ask
 30:      * @param string          $default  The default answer if none is given by the user
 31:      *
 32:      * @return string The user answer
 33:      *
 34:      * @throws \RuntimeException If there is no data to read in the input stream
 35:      */
 36:     public function ask(OutputInterface $output, $question, $default = null)
 37:     {
 38:         $output->write($question);
 39: 
 40:         $ret = fgets($this->inputStream ?: STDIN, 4096);
 41:         if (false === $ret) {
 42:             throw new \RuntimeException('Aborted');
 43:         }
 44:         $ret = trim($ret);
 45: 
 46:         return strlen($ret) > 0 ? $ret : $default;
 47:     }
 48: 
 49:     /**
 50:      * Asks a confirmation to the user.
 51:      *
 52:      * The question will be asked until the user answers by nothing, yes, or no.
 53:      *
 54:      * @param OutputInterface $output   An Output instance
 55:      * @param string|array    $question The question to ask
 56:      * @param Boolean         $default  The default answer if the user enters nothing
 57:      *
 58:      * @return Boolean true if the user has confirmed, false otherwise
 59:      */
 60:     public function askConfirmation(OutputInterface $output, $question, $default = true)
 61:     {
 62:         $answer = 'z';
 63:         while ($answer && !in_array(strtolower($answer[0]), array('y', 'n'))) {
 64:             $answer = $this->ask($output, $question);
 65:         }
 66: 
 67:         if (false === $default) {
 68:             return $answer && 'y' == strtolower($answer[0]);
 69:         }
 70: 
 71:         return !$answer || 'y' == strtolower($answer[0]);
 72:     }
 73: 
 74:     /**
 75:      * Asks for a value and validates the response.
 76:      *
 77:      * The validator receives the data to validate. It must return the
 78:      * validated data when the data is valid and throw an exception
 79:      * otherwise.
 80:      *
 81:      * @param OutputInterface $output    An Output instance
 82:      * @param string|array    $question  The question to ask
 83:      * @param callback        $validator A PHP callback
 84:      * @param integer         $attempts  Max number of times to ask before giving up (false by default, which means infinite)
 85:      * @param string          $default  The default answer if none is given by the user
 86:      *
 87:      * @return mixed
 88:      *
 89:      * @throws \Exception When any of the validators return an error
 90:      */
 91:     public function askAndValidate(OutputInterface $output, $question, $validator, $attempts = false, $default = null)
 92:     {
 93:         $error = null;
 94:         while (false === $attempts || $attempts--) {
 95:             if (null !== $error) {
 96:                 $output->writeln($this->getHelperSet()->get('formatter')->formatBlock($error->getMessage(), 'error'));
 97:             }
 98: 
 99:             $value = $this->ask($output, $question, $default);
100: 
101:             try {
102:                 return call_user_func($validator, $value);
103:             } catch (\Exception $error) {
104:             }
105:         }
106: 
107:         throw $error;
108:     }
109: 
110:     /**
111:      * Sets the input stream to read from when interacting with the user.
112:      *
113:      * This is mainly useful for testing purpose.
114:      *
115:      * @param resource $stream The input stream
116:      */
117:     public function setInputStream($stream)
118:     {
119:         $this->inputStream = $stream;
120:     }
121: 
122:     /**
123:      * Returns the helper's input stream
124:      *
125:      * @return string
126:      */
127:     public function getInputStream()
128:     {
129:         return $this->inputStream;
130:     }
131: 
132:     /**
133:      * Returns the helper's canonical name.
134:      */
135:     public function getName()
136:     {
137:         return 'dialog';
138:     }
139: }
140: