question_file = $PLUGINS_DIR . "Captcha/";
if(file_exists($this->question_file . $LANG . "_questions.txt"))
$this->question_file .= $LANG . "_questions.txt";
else
$this->question_file .= "en_questions.txt";
$this->cookie_password = md5($_SERVER["SCRIPT_FILENAME"]); // pseudo random string
}
/*
* This is for the possibility of authentization during the preview
*/
function actionBegin()
{
global $preview;
if($_REQUEST["qid"] && $preview)
$this->checkCaptcha();
}
/*
Functions return number of questions in question file. Method is very simple, it just counts number of occurence of "--" at the begining of the line.
*/
function questionCount()
{
$count = 0;
$q = fopen($this->question_file, "r");
if(!$q) {
echo "Captcha plugin: Can't open captcha questions file $this->question_file.";
return 0; // Oops
}
while($line = fgets($q))
if(!strcmp(trim($line), "--"))
$count++;
fclose($q);
return $count;
}
/*
Function returns $line. line of $i. question. Convention is that 1. line is question and second line is answer(s). Numbering is Pascal-like, that means that getQuestion(1, 1) returns 1. line of 1. question.
*/
function getQuestion($i, $line)
{
$count = 0;
$q = fopen($this->question_file, "r");
if(!$q) {
echo "Captcha plugin: Can't open captcha questions file $this->question_file.";
return 0; // Oops
}
$str = "";
while($l = fgets($q)) {
if(!strcmp(trim($l), "--")) {
$count++;
if($count == $i) {
for($k = 0, $str = ""; $k < $line && $str = fgets($q); $k++);
break;
}
}
}
fclose($q);
return $str;
}
/*
* By convention, writingPage hook is expected to return false if
* everything is ok and true if page should not be saved.
*/
function checkCaptcha()
{
global $PASSWORD, $error;
if(!empty($PASSWORD) || ($this->permanent && $_COOKIE["LW_CAPTCHA"] == $this->cookie_password))
return false;
$question_id = $_REQUEST["qid"];
$answer = trim($_REQUEST["ans"]);
if(empty($question_id) || empty($answer) || !is_numeric($question_id))
return true;
$right_answers = explode(",", $this->getQuestion($question_id, 2));
$equals = false;
foreach($right_answers as $a)
if(!strcasecmp(trim($a), $answer)) {
$equals = true;
$_COOKIE['LW_CAPTCHA'] = $this->cookie_password;
if($this->permanent)
setcookie('LW_CAPTCHA', $this->cookie_password, time() + 365 * 24 * 3600);
break;
}
if(!$equals)
$error = "Captcha plugin: Given answer is not correct. Try again.";
return !$equals;
}
function writingPage() { return $this->checkCaptcha(); }
/*
* If JavaScript is enabled, user does not have to fill the form ...
*
* We rely on that spam bots don't interpret javascript.
*/
function fillAnswerWithJavascript($question_id)
{
$answers = explode(",", $this->getQuestion($question_id, 2));
return '
';
}
function template()
{
global $html, $PASSWORD, $action, $preview, $HEAD;
if(($action != "edit" && !$preview) || !empty($PASSWORD)
|| ($this->permanent && $_COOKIE["LW_CAPTCHA"] == $this->cookie_password))
return;
$question_count = $this->questionCount();
$question_id = rand(1, $question_count);
$question_text = trim($this->getQuestion($question_id, 1));
$html = template_replace("plugin:CAPTCHA_QUESTION", '' . $question_text . "", $html);
$html = template_replace("plugin:CAPTCHA_INPUT", "", $html);
$HEAD .= $this->fillAnswerWithJavascript($question_id);
}
function commentsTemplate()
{
global $comments_html, $PASSWORD, $HEAD;
if(!empty($PASSWORD) || ($this->permanent && $_COOKIE["LW_CAPTCHA"] == $this->cookie_password)) {
$comments_html = template_replace("plugin:CAPTCHA_QUESTION", "", $comments_html);
$comments_html = template_replace("plugin:CAPTCHA_INPUT", "", $comments_html);
return;
}
$question_count = $this->questionCount();
$question_id = rand(1, $question_count);
$question_text = trim($this->getQuestion($question_id, 1));
$comments_html = template_replace("plugin:CAPTCHA_QUESTION", '' . $question_text . "", $comments_html);
$comments_html = template_replace("plugin:CAPTCHA_INPUT", "", $comments_html);
$HEAD .= $this->fillAnswerWithJavascript($question_id);
}
}