Change password function not working - hash wrong - cakephp

Question

Ok, I've been hitting my head against this wall all evening.
Can someone explain to my why this returns false (user model):
public function changePassword($user_id, $currentPassword, $newPassword, $repeatPassword){
//Check repeat
/*
if($newPassword != $repeatPassword)
return false;
*/
//Check old password
$this->id = $user_id;
$current = $this->field('password');
$passwordHasher = new BlowfishPasswordHasher();
$hash = $passwordHasher->hash($currentPassword);
if($current != $hash)
return false;
//set password to data
//save
return true;
}
public function beforeSave($options = array()) {
if(isset($this->data[$this->alias]['password'])) {
$passwordHasher = new BlowfishPasswordHasher();
$this->data[$this->alias]['password'] = $passwordHasher->hash($this->data[$this->alias]['password']);
}
return true;
}
I can see from debugging $current and $hash that the generated hash is not the same as the one pulled from the database. Question is why.
Login works fine by the way. CakePHP version is 2.6.5
EDIT:
Problem solved. Complete solution here:
public function changePassword($user_id, $currentPassword, $newPassword, $repeatPassword){
//Check repeat
if($newPassword != $repeatPassword)
return false;
//Check old password
$this->id = $user_id;
$current = $this->field('password');
$passwordHasher = new BlowfishPasswordHasher();
if(!$passwordHasher->check($currentPassword, $current))
return false;
//set password to data
$this->data['password'] = $newPassword;
//save
if(!$this->save($this->data))
return false;
return true;
}
public function beforeSave($options = array()) {
if(isset($this->data[$this->alias]['password'])) {
$passwordHasher = new BlowfishPasswordHasher();
$this->data[$this->alias]['password'] = $passwordHasher->hash($this->data[$this->alias]['password']);
}
return true;
}

Answer 1

$current and $hash that the generated hash is not the same
That's how blowfish works. It generates a new hash each time.
Instead of hashing the current password and doing string comparison with existing hash from datbase use BlowfishPasswordHasher::check() to check if current password matches hash from database.