ascii_art_captcha.module in CAPTCHA Pack 6

File

ascii_art_captcha/ascii_art_captcha.module

<?php

/**
 * Implementation of hook_help().
 */
function ascii_art_captcha_help($path, $arg) {
  switch ($path) {
    case 'admin/user/captcha/ascii_art_captcha':
      $output = '<p>' . t('The ASCII art CAPTCHA shows a random character code in ASCII art style. Example with current settings:') . '</p>';
      $captcha = ascii_art_captcha_captcha('generate', 'ASCII art CAPTCHA');
      $output .= $captcha['form']['ascii']['#value'];
      return $output;
  }
}

/**
 * Implementation of hook_menu().
 */
function ascii_art_captcha_menu() {
  $items = array();
  $items['admin/user/captcha/ascii_art_captcha'] = array(
    'title' => 'ASCII art CAPTCHA',
    'file' => 'ascii_art_captcha.admin.inc',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'ascii_art_captcha_settings_form',
    ),
    'access arguments' => array(
      'administer CAPTCHA settings',
    ),
    'type' => MENU_LOCAL_TASK,
  );
  return $items;
}

/**
 * helper function for generating a code, taking the allowed characters into account
 */
function _ascii_art_captcha_get_allowed_characters() {
  $allowed_chars = array();
  $allowed_chars_settings = variable_get('ascii_art_captcha_allowed_characters', drupal_map_assoc(array(
    'upper',
    'lower',
    'digit',
  )));
  if ($allowed_chars_settings['upper']) {
    $allowed_chars = array_merge($allowed_chars, array(
      'A',
      'B',
      'C',
      'D',
      'E',
      'F',
      'G',
      'H',
      'I',
      'J',
      'K',
      'L',
      'M',
      'N',
      'P',
      'Q',
      'R',
      'S',
      'T',
      'U',
      'V',
      'W',
      'X',
      'Y',
      'Z',
    ));
  }
  if ($allowed_chars_settings['lower']) {
    $allowed_chars = array_merge($allowed_chars, array(
      'a',
      'b',
      'c',
      'd',
      'e',
      'f',
      'g',
      'h',
      'i',
      'j',
      'k',
      'l',
      'm',
      'n',
      'p',
      'q',
      'r',
      's',
      't',
      'u',
      'v',
      'w',
      'x',
      'y',
      'z',
    ));
  }
  if ($allowed_chars_settings['digit']) {
    $allowed_chars += array_merge($allowed_chars, array(
      '1',
      '2',
      '3',
      '4',
      '5',
      '6',
      '7',
      '8',
      '9',
    ));
  }
  return $allowed_chars;
}

/**
 * Implementation of hook_captcha
 */
function ascii_art_captcha_captcha($op, $captcha_type = '', $response = '') {
  switch ($op) {
    case 'list':
      return array(
        'ASCII art CAPTCHA',
      );
    case 'generate':
      if ($captcha_type == "ASCII art CAPTCHA") {

        // get settings
        $allowed_chars = _ascii_art_captcha_get_allowed_characters();
        $code_length = (int) variable_get('ascii_art_captcha_code_length', 6);

        // load font
        $font_name = variable_get('ascii_art_captcha_font', 'standard');
        if (!(include_once 'fonts/ascii_art_captcha_font_' . $font_name . '.inc')) {
          return;
        }
        $font = call_user_func('ascii_art_captcha_font_' . $font_name);
        if (!$font) {
          return;
        }

        // build solution and ASCII art array
        $solution = '';
        $ascii_lines = array();
        for ($i = 0; $i < $font['height']; $i++) {
          $ascii_lines[$i] = '';
        }
        for ($i = 0; $i < $code_length; $i++) {
          $character = $allowed_chars[array_rand($allowed_chars)];
          $solution .= $character;
          foreach ($font[$character] as $l => $cline) {
            $ascii_lines[$l] .= ' ' . check_plain($cline);
          }
        }

        // build CAPTCHA array
        $captcha = array();
        $captcha['solution'] = $solution;
        $style = 'line-height:1.1;';
        if (variable_get('ascii_art_captcha_font_size', 0)) {
          $style .= 'font-size:' . variable_get('ascii_art_captcha_font_size', 0) . 'pt;';
        }
        $captcha['form']['ascii'] = array(
          '#type' => 'markup',
          '#value' => '<pre class="ascii_art_captcha" style="' . $style . '">' . implode('<br />', $ascii_lines) . '</pre>',
        );
        $captcha['form']['captcha_response'] = array(
          '#type' => 'textfield',
          '#title' => t('Enter the code above'),
          '#size' => 10,
          '#maxlength' => 10,
          '#required' => TRUE,
          '#description' => t('Enter the code depicted in ASCII art style.'),
        );
        return $captcha;
      }
      break;
  }
}

Functions

Name	Description
ascii_art_captcha_captcha	Implementation of hook_captcha
ascii_art_captcha_help	Implementation of hook_help().
ascii_art_captcha_menu	Implementation of hook_menu().
_ascii_art_captcha_get_allowed_characters	helper function for generating a code, taking the allowed characters into account