<?php

class App_Form_Newsletter_Obj extends App_Form_Newsletter_Abstract_Obj
{
    const NOT_EXISTS = 0;
    const SUBSCRIBED = 1;
    const UNSUBSCRIBED = 2;

    public function validateForm($data)
    {
        $errors = array();

        if (!empty($data['email'])) {
            $status = $this->getSubscriptionStatus($data['email']);
            if (static::SUBSCRIBED === $status) {
                $errors['email'] = 'This email address is already subscribed.';
            } else if (static::UNSUBSCRIBED === $status) {
                $errors['email'] = 'This email address is unsubscribed.';
            }
        }

        return (empty($errors)) ? true : $errors;
    }

    /**
     * Function returns subscription status code for user specified by email
     * 0 - subscribtion not exists
     * 1 - subscribtion exists
     * 2 - user is unsubscribed
     *
     * @param string $email
     * @return int
     */
    public function getSubscriptionStatus($email)
    {
        $select = $this->_db->select();
        $select->from($this->_getPair(), array('subscribed'));
        $select->where('`email` = ?', $email);
        $select->limit(1);
        $subscribed = $this->_db->fetchOne($select);

        $status = null;
        if (empty($subscribed)) {
            $status = static::NOT_EXISTS;
        } else {
            $status = ('y' == $subscribed) ? static::SUBSCRIBED : static::UNSUBSCRIBED;
        }
        return $status;
    }
}