function get_captcha($seed)
{
$digits = captcha_get_digits();
// Initialize the RNG
srand($seed);
$k = array_rand($digits, 2);
if (rand(0, 1) == 1) {
$value = $k[0] + $k[1];
$text = $digits[$k[0]] . " plus " . $digits[$k[1]];
} else {
// Swap when digit 1 is less than digit 2, this makes sure we don't get negative values
if ($k[1] > $k[0]) {
$tmp = $k[0];
$k[0] = $k[1];
$k[1] = $tmp;
}
$value = $k[0] - $k[1];
$text = $digits[$k[0]] . " minus " . $digits[$k[1]];
}
return array('seed' => $seed, 'value' => $value, 'text' => $text);
}
/**
* Validate captcha input.
*
* @param string $str The text of the captcha
*
* @return bool
*/
function cinput_check($str)
{
$str = $this->input->post('cinput');
if (!is_numeric($str)) {
// If the user input is not numeric, convert it to a numeric value
$this->load->plugin('captcha');
$digits = captcha_get_digits(true);
$str = array_search(strtolower($str), $digits);
}
if ($str != $this->session->userdata('cinput')) {
$this->validation->_error_messages['cinput_check'] = 'Incorrect captcha.';
return false;
}
return true;
}
