/**
* Checks if the cache is up-to-date
*
* @param string Mailbox name
* @param string Internal cache key
* @return int Cache status: -3 = off, -2 = incomplete, -1 = dirty
*/
private function check_cache_status($mailbox, $cache_key)
{
if (!$this->caching_enabled) {
return -3;
}
$cache_index = $this->get_message_cache_index($cache_key);
$msg_count = $this->_messagecount($mailbox);
$cache_count = count($cache_index);
// empty mailbox
if (!$msg_count) {
return $cache_count ? -2 : 1;
}
// @TODO: We've got one big performance problem in cache status checking method
// E.g. mailbox contains 1000 messages, in cache table we've got first 100
// of them. Now if we want to display only that 100 (which we've got)
// check_cache_status returns 'incomplete' and messages are fetched
// from IMAP instead of DB.
if ($cache_count == $msg_count) {
if ($this->skip_deleted) {
$h_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, "1:*", 'UID', $this->skip_deleted);
if (sizeof($h_index) == $cache_count) {
$cache_index = array_flip($cache_index);
foreach ($h_index as $idx => $uid) {
unset($cache_index[$uid]);
}
if (empty($cache_index)) {
return 1;
}
}
return -2;
} else {
// get UID of message with highest index
$uid = iil_C_ID2UID($this->conn, $mailbox, $msg_count);
$cache_uid = array_pop($cache_index);
// uids of highest message matches -> cache seems OK
if ($cache_uid == $uid) {
return 1;
}
}
// cache is dirty
return -1;
} else {
if (abs($msg_count - $cache_count) < $msg_count / 10) {
return -1;
} else {
return -2;
}
}
}
/**
* @access private
*/
function sync_header_index($mailbox)
{
$cache_key = $mailbox . '.msg';
$cache_index = $this->get_message_cache_index($cache_key);
$msg_count = $this->_messagecount($mailbox);
// fetch complete message index
$a_message_index = iil_C_FetchHeaderIndex($this->conn, $mailbox, "1:{$msg_count}", 'UID');
foreach ($a_message_index as $id => $uid) {
// message in cache at correct position
if ($cache_index[$id] == $uid) {
unset($cache_index[$id]);
continue;
}
// message in cache but in wrong position
if (in_array((string) $uid, $cache_index, TRUE)) {
unset($cache_index[$id]);
}
// other message at this position
if (isset($cache_index[$id])) {
$this->remove_message_cache($cache_key, $id);
unset($cache_index[$id]);
}
// fetch complete headers and add to cache
$headers = iil_C_FetchHeader($this->conn, $mailbox, $id);
$this->add_message_cache($cache_key, $headers->id, $headers);
}
// those ids that are still in cache_index have been deleted
if (!empty($cache_index)) {
foreach ($cache_index as $id => $uid) {
$this->remove_message_cache($cache_key, $id);
}
}
}