phrase_captcha.module in CAPTCHA Pack 6

File

text_captcha/phrase_captcha/phrase_captcha.module

<?php

/**
 * Implementation of a phrase based CAPTCHA, for use with the CAPTCHA module
 *
 * @todo: add character picking of current word, which is harder for spam bots
 * than plain word guessing.
 */
require_once drupal_get_path('module', 'phrase_captcha') . '/../text_captcha.inc';
define('PHRASE_CAPTCHA_GENERATE_NONSENSE_WORDS', 0);
define('PHRASE_CAPTCHA_USER_DEFINED_WORDS', 1);

/**
 * Implementation of hook_help().
 */
function phrase_captcha_help($path, $arg) {
  switch ($path) {
    case 'admin/user/captcha/phrase_captcha':
      return '<p>' . t('This phrase based CAPTCHA presents a CAPTCHA phrase of a given number of words and asks to pick the right word (based on counting, alphabetical order, etc).') . '</p>';
  }
}

/**
 * Implementation of hook_menu().
 */
function phrase_captcha_menu() {
  $items = array();

  // add an administration tab for phrase_captcha
  $items['admin/user/captcha/phrase_captcha'] = array(
    'title' => 'Phrase CAPTCHA',
    'file' => 'phrase_captcha.admin.inc',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'phrase_captcha_settings_form',
    ),
    'access arguments' => array(
      'administer CAPTCHA settings',
    ),
    'type' => MENU_LOCAL_TASK,
  );
  return $items;
}

/**
 * Implementation of hook_captcha
 */
function phrase_captcha_captcha($op, $captcha_type = '') {
  switch ($op) {
    case 'list':
      return array(
        'Phrase CAPTCHA',
      );
    case 'generate':
      if ($captcha_type == 'Phrase CAPTCHA') {
        require_once 'phrase_captcha.inc';

        // generate words
        $words = _phrase_captcha_generate_words((int) variable_get('phrase_captcha_word_quantity', 5));

        // pick a random word selection challenge
        $word_challenges = _phrase_captcha_enabled_word_challenges();
        $key = array_rand($word_challenges);
        $function = $word_challenges[$key];
        list($phrase_words, $question, $solution) = call_user_func($function, $words);

        // build options list
        $all_words = array_merge($words, _phrase_captcha_generate_words((int) variable_get('phrase_captcha_additional_word_quantity', 1)));
        shuffle($all_words);
        $options = array();
        foreach ($all_words as $word) {
          $options[$word] = $word;
        }

        // store the answer and build the form elements
        $captcha = array();
        $captcha['solution'] = $solution;
        $captcha['form']['captcha_phrase'] = array(
          '#type' => 'markup',
          '#value' => '"' . implode(' ', $phrase_words) . '"',
          '#weight' => -2,
        );
        $captcha['form']['captcha_response'] = array(
          '#type' => 'radios',
          '#title' => $question,
          '#options' => $options,
          // extra class needed for additional CSS'ing of the options
          '#attributes' => array(
            'class' => 'text-captcha-word-list-radios',
          ),
          // The following entry '#DANGEROUS_SKIP_CHECK' is needed to prevent
          // that Drupal checks during validation phase if a submitted option
          // is in the list of possible options. (see includes/form.inc)
          // The options are randomly generated on each call and consequently
          // almost never the same during the generate phase and the validation
          // phase.
          '#DANGEROUS_SKIP_CHECK' => TRUE,
          //
          '#required' => TRUE,
        );

        // additional text CAPTCHA CSS rules
        drupal_add_css(drupal_get_path('module', 'phrase_captcha') . '/../text_captcha.css');
        return $captcha;
      }
  }
}

Functions

Name	Description
phrase_captcha_captcha	Implementation of hook_captcha
phrase_captcha_help	Implementation of hook_help().
phrase_captcha_menu	Implementation of hook_menu().

Constants

Name	Description
PHRASE_CAPTCHA_GENERATE_NONSENSE_WORDS
PHRASE_CAPTCHA_USER_DEFINED_WORDS