<?php
use \Doctrine\ORM;
class Application_Auth_Adapter implements Zend_Auth_Adapter_Interface {
    private $username;
    private $password;

    function __construct($username, $password) {
        $this->username = $username;
        $this->password = $password;
    }

    function authenticate() {
$em = Zend_Registry::get('em');
$query = $em->createQuery('select u from Application\Models\User u WHERE u.name = :username')
            ->setParameter('username', $this->username);
        try {
            $user = $query->getSingleResult();
            $salt = $user->salt;
            $hashedPassword = hash_hmac('sha256', $this->password, $salt);
            if ($hashedPassword == $user->password) {
                // login success
                return new Zend_Auth_Result(Zend_Auth_Result::SUCCESS, $user);
            } else {
                // wrong password
                return new Zend_Auth_Result(Zend_Auth_Result::FAILURE_CREDENTIAL_INVALID, null, array('Wrong password'));
            }
        } catch (ORM\NonUniqueResultException $e) {
            // non unique result
            return new Zend_Auth_Result(Zend_Auth_Result::FAILURE, null, array('Non unique username'));
        } catch (ORM\NoResultException $e) {
            // no result found
            return new Zend_Auth_Result(Zend_Auth_Result::FAILURE_IDENTITY_NOT_FOUND, null, array('User not found'));
        } catch (Exception $e) {
            // exception occured
            return new Zend_Auth_Result(Zend_Auth_Result::FAILURE, null, array('Authentication failed 2'));
        }
    }
}