function encode_header($str = null, $charset = null, $encoding = null, $len = null, $end = null, $debug = null)
{
if (!FUNC4::is_debug($debug)) {
$debug = debug_backtrace();
}
$_mime = new MIME4();
$err = array();
if (!is_string($str)) {
$err[] = 'invalid argument type';
}
if ($charset == null) {
$charset = $_mime->HCHARSET;
} else {
if (!is_string($charset)) {
$err[] = 'invalid charset type';
} else {
if (!(strlen($charset) >= 2 && FUNC4::is_alpha($charset, true, '-'))) {
$err[] = 'invalid charset value';
}
}
}
if ($encoding == null) {
$encoding = $_mime->HENCDEF;
} else {
if (!is_string($encoding)) {
$err[] = 'invalid encoding type';
} else {
$encoding = strtolower(FUNC4::str_clear($encoding));
if (!isset($_mime->hencarr[$encoding])) {
$err[] = 'invalid encoding value';
}
}
}
if ($len == null) {
$len = $_mime->HLEN;
} else {
if (!(is_int($len) && $len > 1)) {
$err[] = 'invalid line length value';
}
}
if ($end == null) {
$end = $_mime->LE;
} else {
if (!is_string($end)) {
$err[] = 'invalid line end value';
}
}
if (count($err) > 0) {
FUNC4::trace($debug, implode(', ', $err));
} else {
if ($str == '') {
return $str;
} else {
$enc = false;
$dif = $len - strlen('=?' . $charset . '?X??=');
if ($encoding == 'quoted-printable') {
if (!MIME4::is_printable($str)) {
$new = $dif - 4 > 2 ? $dif - 4 : $len;
$enc = MIME4::qp_encode($str, $new, $end);
$enc = str_replace(array('?', ' ', '=' . $end), array('=3F', '_', $end), $enc);
}
} else {
if ($encoding == 'base64') {
$new = $dif > 3 ? $dif : $len;
if ($new > 3) {
for ($i = $new; $i > 2; $i--) {
$crt = '';
for ($j = 0; $j <= $i; $j++) {
$crt .= 'x';
}
if (strlen(base64_encode($crt)) <= $new) {
$new = $i;
break;
}
}
}
$cnk = rtrim(chunk_split($str, $new, $end));
$imp = array();
foreach (explode($end, $cnk) as $line) {
if ($line != '') {
$imp[] = base64_encode($line);
}
}
$enc = implode($end, $imp);
}
}
$res = array();
if ($enc) {
$chr = $encoding == 'base64' ? 'B' : 'Q';
foreach (explode($end, $enc) as $val) {
if ($val != '') {
$res[] = '=?' . $charset . '?' . $chr . '?' . $val . '?=';
}
}
} else {
$cnk = rtrim(chunk_split($str, $len, $end));
foreach (explode($end, $cnk) as $val) {
if ($val != '') {
$res[] = $val;
}
}
}
return implode($end . "\t", $res);
}
}
}
