/**
* Calculate the differences between two strings.
* $a: Initial string
* $b: Changed string
* $min: (optional) minum match length
* return: array of changes
*/
function phorum_diff($a, $b, $min = 3, $i = 0)
{
$diff = array();
if ($a == "" && $b == "") {
return $diff;
}
$a = str_replace(array("\r\n", "\r"), "\n", $a);
$b = str_replace(array("\r\n", "\r"), "\n", $b);
if ($a == "") {
array_push($diff, "{$i}+" . $b);
return $diff;
}
if ($b == "") {
array_push($diff, "{$i}-" . $a);
return $diff;
}
$match = phorum_diff_match($a, $b);
if (strlen($match) < $min) {
array_push($diff, "{$i}-" . $a);
array_push($diff, "{$i}+" . $b);
return $diff;
}
$ap = strpos($a, $match);
$bp = strpos($b, $match);
$diff = phorum_diff(substr($a, 0, $ap), substr($b, 0, $bp), $min, $i);
return array_merge($diff, phorum_diff(substr($a, $ap + strlen($match)), substr($b, $bp + strlen($match)), $min, $i + $bp + strlen($match)));
}
$sort = PHORUM_SORT_DEFAULT;
break;
}
$dbmessage["sort"] = $sort;
}
} else {
// set some key fields to the same values as the first message in the thread
$dbmessage["forum_id"] = $top_parent["forum_id"];
$dbmessage["sort"] = $top_parent["sort"];
}
// Update the editing info in the meta data.
$dbmessage["meta"]["show_signature"] = $message["show_signature"];
// we are doing the diffs here to know about changes for edit-counts
// $origmessage loaded in check_permissions
$diff_body = phorum_diff($origmessage["body"], $message["body"]);
$diff_subject = phorum_diff($origmessage["subject"], $message["subject"]);
if (!empty($diff_body) || !empty($diff_subject)) {
$name = phorum_api_user_get_display_name($PHORUM["user"]["user_id"], NULL, PHORUM_FLAG_PLAINTEXT);
$dbmessage["meta"]["edit_count"] = isset($message["meta"]["edit_count"]) ? $message["meta"]["edit_count"] + 1 : 1;
$dbmessage["meta"]["edit_date"] = time();
$dbmessage["meta"]["edit_username"] = $name;
$dbmessage["meta"]["edit_user_id"] = $PHORUM["user"]["user_id"];
// perform diff if edit tracking is enabled
if (!empty($PHORUM["track_edits"])) {
$edit_data = array("diff_body" => $diff_body, "diff_subject" => $diff_subject, "time" => $dbmessage["meta"]["edit_date"], "user_id" => $PHORUM["user"]["user_id"], "message_id" => $dbmessage['message_id']);
phorum_db_add_message_edit($edit_data);
}
}
// Update attachments in the meta data, link active attachments
// to the message and delete stale attachments.
$dbmessage["meta"]["attachments"] = array();
