}
}
}
+ return $this->handleRfc2231($properties);
+ }
+
+ /**
+ * Joins RFC-2231 continuations, converts encoding to RFC-2047 style
+ * @param array $properties
+ * @return array
+ */
+ function handleRfc2231($properties) {
+
+ /* STAGE 1: look for multi-line parameters, convert to the single line
+ form, and normalize values */
+
+ $cont = array();
+ foreach($properties as $key=>$value) {
+ /* Look for parameters followed by "*", a number, and an optional "*"
+ at the end. */
+ if (preg_match('/^(.*\*)(\d+)(|\*)$/', $key, $matches)) {
+ unset($properties[$key]);
+ $prop_name = $matches[1];
+ if (!isset($cont[$prop_name])) $cont[$prop_name] = array();
+
+ /* An asterisk at the end of parameter name indicates that there
+ may be an encoding information present, and the parameter
+ value is percent-hex encoded. If parameter is not encoded, we
+ encode it to simplify further processing.
+ */
+ if ($matches[3] == '') $value = rawurlencode($value);
+ /* Use the number from parameter name as segment index */
+ $cont[$prop_name][$matches[2]] = $value;
+ }
+ }
+ foreach($cont as $key=>$values) {
+ /* Sort segments of multi-line parameters by index number. */
+ ksort($values);
+ /* Join segments. We can do it safely, because:
+ - All segments are encoded.
+ - Per RFC-2231, chapter 4.1 notes.
+ */
+ $value = implode('', $values);
+ /* Add language and character set field delimiters if not present,
+ as required per RFC-2231, chapter 4.1, note #5. */
+ if (strpos($value, "'") === false) $value = "''".$value;
+ $properties[$key] = $value;
+ }
+
+ /* STAGE 2: Convert single line RFC-2231 encoded parameters, and
+ previously converted multi-line parameters, to RFC-2047 encoding */
+
+ foreach($properties as $key=>$value) {
+ if ($idx = strpos($key, '*')) {
+ unset($properties[$key]);
+ /* Extract the charset & language. */
+ $charset = substr($value,0,strpos($value,"'"));
+ $value = substr($value,strlen($charset)+1);
+ $language = substr($value,0,strpos($value,"'"));
+ $value = substr($value,strlen($language)+1);
+ /* No character set defaults to US-ASCII */
+ if (!$charset) $charset = 'US-ASCII';
+ if ($language) $language = '*'.$language;
+ /* Convert to RFC-2047 base64 encoded string. */
+ $properties[substr($key, 0, $idx)] = '=?'.$charset.$language.'?B?'.base64_encode(rawurldecode($value)).'?=';
+ }
+ }
return $properties;
}