Forgotten Password Logic

[eluser]xtremer360[/eluser]
I'm just trying to see if anyone disagrees with the way I'm handling my logic for this. Something doesn't feel right with it but I don't quite know what it is.

Just wanted to add that the new_password_key is NOT a password for the user to log in with. As of right now I was going to have them directed to a page from a link in an email where they can enter a new password.

Code:

function forgot_password_submit()
    {
        $this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean');
        
        if (!$this->form_validation->run())
        {
            echo json_encode(array('error' => 'yes', 'message' => 'There was a problem submitting the form! Please refresh the window and try again!'));    
        }
        else
        {
            if (!is_null($user_data = $this->users->get_user_by_username($this->input->post('username'))))
            {
                if (!isset($user_data->new_password_key) && (!isset($user_data->new_password_requested)))
                {                
                    if(!strtotime($user_data->new_password_requested) >= (time() - 172800))
                    {
                        echo json_encode(array('error' => 'yes', 'message' => 'You have to wait 2 days before a new temp password can be emailed!'));
                    }
                    else
                    {
                        if ($this->kow_auth->forgot_password($this->input->post('username')))
                        {
                            $this->kow_auth->send_email('forgot_password', 'KOW Manager Forgot Password Email', $user_data);
                            echo json_encode(array('success' => 'yes', 'message' => 'A temporary password has been emailed to you!'));
                        }
                        else
                        {
                            echo json_encode(array('error' => 'yes', 'message' => 'A !'));
                        }  
                    }
                }
                else
                {
                    echo json_encode(array('success' => 'yes', 'message' => 'Check your email for your temporary password!'));
                }
            }
            else
            {
                echo json_encode(array('error' => 'yes', 'message' => 'User does not exist in the database!'));
            }
        
        }          
    }

EDIT

This is what Im going to use for the controller. There just seems to be some logic issues I have with it because what if it gets down to the if statement if ($already_sent_password) and for some reason they didn't get it. Then what? Or what if itt gets down to if (!strtotime($user_data->new_password_requested) <= (time() - 172800)) which is starting to sounds stupid to me because why make them have to wait two days to get a new password key.

Code:

function forgot_password_submit()
{
    $this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean');

    if (!$this->form_validation->run())
    {
        $this->kow_auth->output('There was a problem submitting the form! Please refresh the window and try again!', FALSE);
        return;
    }

    $user_data = $this->users->get_user_by_username($this->input->post('username'));
    if ($user_data === NULL)
    {
        $this->kow_auth->output('User does not exist in the database!', FALSE);
        return;
    }

    $already_sent_password = (isset($user_data->new_password_key) && isset($user_data->new_password_requested));
    if ($already_sent_password)
    {
        $this->kow_auth->output('Check your email for your temporary password!');
        return;
    }

    if (!strtotime($user_data->new_password_requested) <= (time() - 172800))
    {
        $this->kow_auth->output('You have to wait 2 days before a new temp password can be emailed!', FALSE);
    }
    else
    {
        if ($this->kow_auth->forgot_password($this->input->post('username')))
        {
            $this->kow_auth->send_email('forgot_password', 'KOW Manager Forgot Password Email', $user_data);
            $this->kow_auth->output('A temporary password has been emailed to you!');
        }
        else
        {
            $this->kow_auth->output('A temporary password could not be created for you!', FALSE);
        }
    }
}