added lock mechanism for persons, outsourced infocenter code to javascript

application/models/system/PersonLock_model.php

@@ -0,0 +1,90 @@
+<?php
+
+/**
+ * Enables content locking.
+ * An entry in the locktable means certain content is marked locked and a user is its editor.
+ */
+class PersonLock_model extends DB_Model
+{
+	/**
+	 * Constructor
+	 */
+	public function __construct()
+	{
+		parent::__construct();
+		$this->dbTable = 'system.tbl_person_lock';
+		$this->pk = 'lock_id';
+	}
+
+	/**
+	 * checks if a specific person is locked. By default, looks for any entries in locktable for the person.
+	 * Alternatively, looks only for locks in a certain app
+	 * @param $person_id
+	 * @param null $app
+	 * @return array all locks for a person if locked, null otherwise
+	 */
+	public function checkIfLocked($person_id, $app = null)
+	{
+		$lockdata = $app === null ? array('person_id' => $person_id) : array('person_id' => $person_id, 'app' => $app);
+
+		$result = $this->loadWhere($lockdata);
+
+		if($result->error)
+			return error($result->retval);
+		else
+		{
+			if(count($result->retval) > 0)
+				return success($result->retval);
+			else
+				return success(null);
+		}
+	}
+
+	/**
+	 * locks a person. returns null if person was not locked (e.g. when already locked)
+	 * @param $person_id
+	 * @param $uid user who locks the person
+	 * @param $app optional, application in which person is locked
+	 * @return array inserted lock id if person was locked, null otherwise
+	 */
+	public function lockPerson($person_id, $uid, $app = null)
+	{
+		$locked = $this->checkIfLocked($person_id, $app);
+
+		if($locked->error)
+			return error($locked->retval);
+
+		//insert only if not already locked
+		if($locked->retval === null)
+			return $this->insert(array('person_id' => $person_id, 'uid' => $uid, 'app' => $app));
+		else
+			return success(null);
+	}
+
+	/**
+	 * remove a lock for a person. By default, removes any entries in locktable for the person
+	 * Alternatively, removes only locks in a certain app
+	 * @param $person_id
+	 * @param null $app
+	 * @return array deleted lock ids if person was locked, null otherwise
+	 */
+	public function unlockPerson($person_id, $app = null)
+	{
+		$deleted = array();
+		$locks = $this->checkIfLocked($person_id, $app);
+
+		if ($locks->retval === null)
+			return success(null);
+
+		foreach ($locks->retval as $lock)
+		{
+			$result = $this->delete($lock->lock_id);
+			if($result->error)
+				return error($result->retval);
+
+			$deleted[] = $lock;
+		}
+
+		return success($deleted);
+	}
+}