/**
Generate CAPTCHA image
@param $_dimx integer
@param $_dimy integer
@param $_len integer
@param $_ttfs string
@public
**/
public static function captcha($_dimx, $_dimy, $_len, $_ttfs = 'cube')
{
$_base = self::rgb(F3::$global['BGCOLOR']);
$_trans = F3::$global['FGTRANS'];
// Specify Captcha seed
if (!strlen(session_id())) {
session_start();
}
$_SESSION['captcha'] = substr(md5(uniqid()), 0, $_len);
F3::$global['SESSION'] =& $_SESSION;
// Font size
$_size = min($_dimx / $_len, 0.6 * $_dimy);
// Load TrueType font file
$_fonts = explode('|', $_ttfs);
$_file = F3::$global['FONTS'] . F3::fixSlashes($_fonts[mt_rand(0, count($_fonts) - 1)]) . '.ttf';
F3::$global['PROFILE']['FILES']['fonts'][basename($_file)] = filesize($_file);
$_maxdeg = 15;
// Compute bounding box metrics
$_bbox = imagettfbbox($_size, $_angle, $_file, $_SESSION['captcha']);
$_wimage = 0.9 * (max($_bbox[2], $_bbox[4]) - max($_bbox[0], $_bbox[6]));
$_himage = max($_bbox[1], $_bbox[3]) - max($_bbox[5], $_bbox[7]);
// Create blank image
$_captcha = imagecreatetruecolor($_dimx, $_dimy);
list($_r, $_g, $_b) = $_base;
$_bg = imagecolorallocate($_captcha, $_r, $_g, $_b);
imagefill($_captcha, 0, 0, $_bg);
$_width = 0;
// Insert each Captcha character
for ($_i = 0; $_i < $_len; $_i++) {
// Random angle
$_angle = $_maxdeg - mt_rand(0, $_maxdeg * 2);
// Get CAPTCHA character from session cookie
$_char = $_SESSION['captcha'][$_i];
$_fg = imagecolorallocatealpha($_captcha, mt_rand(0, 255 - $_trans), mt_rand(0, 255 - $_trans), mt_rand(0, 255 - $_trans), $_trans);
imagettftext($_captcha, $_size, $_angle, ($_dimx - $_wimage) / 2 + $_i * $_wimage / $_len, ($_dimy - $_himage) / 2 + 0.9 * $_himage, $_fg, $_file, $_char);
imagecolordeallocate($_captcha, $_fg);
}
// Make the background transparent
imagecolortransparent($_captcha, $_bg);
// Send output as PNG image
if (PHP_SAPI != 'cli' && !headers_sent()) {
header(F3::HTTP_Content . ': image/png');
}
imagepng($_captcha, NULL, self::PNG_Compress, PNG_NO_FILTER);
// Free resources
imagedestroy($_captcha);
}
/**
Write specified text to log file
@param $_text string
@public
**/
public function write($_text)
{
if (!self::ready()) {
// Lock attempt failed
trigger_error(self::TEXT_LogLock);
return;
}
$_path = F3::$global['LOGS'];
clearstatcache();
if (filesize($_path . $this->filename) > F3::bytes(self::LOG_Size)) {
// Perform log rotation sequence
if (file_exists($_path . $this->filename . '.1')) {
copy($_path . $this->filename . '.1', $_path . $this->filename . '.2');
}
copy($_path . $this->filename, $_path . $this->filename . '.1');
ftruncate($this->handle, 0);
}
// Prepend text with timestamp, source IP, file name and
// line number for tracking origin
$_trace = debug_backtrace(FALSE);
fwrite($this->handle, date('r') . ' [' . $_SERVER['REMOTE_ADDR'] . '] ' . F3::fixSlashes($_trace[0]['file']) . ':' . $_trace[0]['line'] . ' ' . preg_replace('/\\s+/', ' ', $_text) . "\n");
flock($this->handle, LOCK_UN);
}
