class IPN extends ErrorStore
{

    const URL_EMPTY = 'urlEmpty4000';
    const URL_INVALID = 'urlInvalid4001';

    /**
     * AmazonPay module object
     *
     * @var AmazonPay
     */
    private $module;

    /**
     * Sets `$module` member var with dependency injection.
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @param AmazonPay $module
     * @return void
     */
    public function __construct(AmazonPay $module) {
        $this->module = $module;
        parent::__construct();
        $this->populate();
    }

    /**
     * Registers site URL as IPN URL on seller central
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @param array $args
     * @param array $payload
     * @return array
     */
    public function register($args, $payload) {
        $url = $payload['ipnEndpoint'];

        if (empty($url)) {
            return $this->getErrorResponse(self::URL_EMPTY);
        }

        $response = (new EndpointSetter($this->module))->set($url);

        if ((int)$response['ResponseStatus'] !== 200) {
            if (isset($response['Error']['Code'])) {
                if ($response['Error']['Code'] === 'InvalidArgumentsClientError') {
                    return $this->getErrorResponse(self::URL_INVALID, [$response['Error']['Message']]);
                }
            }

            return $this->getErrorResponse(self::INTERNAL_SERVER_ERROR);
        }

        $opts = $this->module->getActingOpts();
        $opts['ipn_endpoint'] = $url;
        $opts['ipn_registered'] = true;
        $this->module->updateActingOpts($opts);

        return 'success';
    }

    /**
     * Populates error store
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return void
     * @throws InvalidArgumentException Thrown if duplicate errorcodes exist.
     */
    public function populate() {
        $this->addError(new GenericError(
            self::URL_EMPTY,
            self::URL_EMPTY,
            400,
            'URL parameter is empty',
            __('Please enter the site URL.', 'wcexaap')
        ));
        $this->addError(new GenericError(
            self::URL_INVALID,
            self::URL_INVALID,
            400,
            function ($message) {
                return $message;
            },
            __('Please enter a valid URL.', 'wcexaap')
        ));
    }
}