--- /dev/null
+<?php
+/**
+ * Laconica, the distributed open-source microblogging tool
+ *
+ * Microid class
+ *
+ * PHP version 5
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category ID
+ * @package Laconica
+ * @author Evan Prodromou <evan@controlyourself.ca>
+ * @copyright 2008 Control Yourself, Inc.
+ * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link http://laconi.ca/
+ */
+
+if (!defined('LACONICA')) {
+ exit(1);
+}
+
+/**
+ * A class for microids
+ *
+ * @category ID
+ * @package Laconica
+ * @author Evan Prodromou <evan@controlyourself.ca>
+ * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link http://laconi.ca/
+ * @see http://microid.org/
+ */
+
+class Microid
+{
+ /** Agent part of the ID. */
+
+ var $agent = null;
+
+ /** Resource part of the ID. */
+
+ var $resource = null;
+
+ /**
+ * Constructor
+ *
+ * @param string $agent Agent of the ID
+ * @param string $resource Resource part
+ */
+
+ function __construct($agent, $resource)
+ {
+ $this->agent = $agent;
+ $this->resource = $resource;
+
+ }
+
+ /**
+ * Generate a MicroID string
+ *
+ * @return string MicroID for agent and resource
+ */
+
+ function toString()
+ {
+ $agent_proto = $this->_getProto($this->agent);
+ $resource_proto = $this->_getProto($this->resource);
+
+ return $agent_proto.'+'.$resource_proto.':sha1:'.
+ sha1(sha1($this->agent).sha1($this->resource));
+ }
+
+ /**
+ * Utility for getting the protocol part of a URI
+ *
+ * @param string $uri URI to parse
+ *
+ * @return string scheme part of the URI
+ */
+
+ function _getProto($uri)
+ {
+ $colon = strpos($uri, ':');
+ return substr($uri, 0, $colon);
+ }
+}