public function encodeHeader($str, $position = 'text')
{
$matchcount = 0;
switch (strtolower($position)) {
case 'phrase':
if (!preg_match('/[\\200-\\377]/', $str)) {
// Can't use addslashes as we don't know the value of magic_quotes_sybase
$encoded = addcslashes($str, ".. \\\"");
if ($str == $encoded and !preg_match('/[^A-Za-z0-9!#$%&\'*+\\/=?^_`{|}~ -]/', $str)) {
return $encoded;
} else {
return "\"{$encoded}\"";
}
}
$matchcount = preg_match_all('/[^\\040\\041\\043-\\133\\135-\\176]/', $str, $matches);
break;
/** @noinspection PhpMissingBreakStatementInspection */
/** @noinspection PhpMissingBreakStatementInspection */
case 'comment':
$matchcount = preg_match_all('/[()"]/', $str, $matches);
// Intentional fall-through
// Intentional fall-through
case 'text':
default:
$matchcount += preg_match_all('/[\\000-\\010\\013\\014\\016-\\037\\177-\\377]/', $str, $matches);
break;
}
//There are no chars that need encoding
if (0 == $matchcount) {
return $str;
}
$maxlen = 75 - 7 - strlen($this->CharSet);
// Try to select the encoding which should produce the shortest output
if ($matchcount > strlen($str) / 3) {
// More than a third of the content will need encoding, so B encoding will be most efficient
$encoding = 'B';
if (function_exists('mb_strlen') and $this->hasMultiBytes($str)) {
// Use a custom function which correctly encodes and wraps long
// multibyte strings without breaking lines within a character
$encoded = $this->base64EncodeWrapMB($str, "\n");
} else {
$encoded = base64_encode($str);
$maxlen -= $maxlen % 4;
$encoded = trim(chunk_split($encoded, $maxlen, "\n"));
}
} else {
$encoding = 'Q';
$encoded = $this->encodeQ($str, $position);
$encoded = $this->wrapText($encoded, $maxlen, true);
$encoded = str_replace('=' . self::CRLF, "\n", trim($encoded));
}
$encoded = preg_replace('/^(.*)$/m', ' =?' . $this->CharSet . "?{$encoding}?\\1?=", $encoded);
$encoded = trim(str_replace("\n", $this->LE, $encoded));
return $encoded;
}
