/**
* Retrieve actual history records that have unused points, i.e. points_delta-points_used > 0
* Update points_used field for non-used points
*
* @param Enterprise_Reward_Model_Reward_History $history
* @param int $required Points total that required
* @return Enterprise_Reward_Model_Mysql4_Reward_History
*/
public function useAvailablePoints($history, $required)
{
$required = (int) abs($required);
if (!$required) {
return $this;
}
$adapter = $this->_getWriteAdapter();
try {
$adapter->beginTransaction();
$select = $adapter->select()->from(array('history' => $this->getMainTable()), array('history_id', 'points_delta', 'points_used'))->where('reward_id = :reward_id')->where('website_id = :website_id')->where('is_expired=0')->where('points_delta - points_used > 0')->order('history_id')->forUpdate(true);
$bind = array(':reward_id' => $history->getRewardId(), ':website_id' => $history->getWebsiteId());
$stmt = $adapter->query($select, $bind);
$updateSqlValues = array();
$data = array();
while ($row = $stmt->fetch()) {
if ($required <= 0) {
break;
}
$rowAvailable = $row['points_delta'] - $row['points_used'];
$pointsUsed = min($required, $rowAvailable);
$required -= $pointsUsed;
$newPointsUsed = $pointsUsed + $row['points_used'];
$data[] = array('history_id' => $row['history_id'], 'points_used' => $newPointsUsed);
}
if (count($data) > 0) {
$adapter->insertOnDuplicate($this->getMainTable(), $data, array('history_id', 'points_used'));
}
$adapter->commit();
} catch (Exception $e) {
$adapter->rollback();
throw $e;
}
return $this;
}
