<?php
/**
 * Queue-based SMTP Mailer.
 *
 * @package ROBOTSTXT_SMTP_Newsletter
 */

namespace Robotstxt_SMTP_Newsletter;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * SMTP Mailer class.
 *
 * Enqueues emails to database for asynchronous processing by external workers.
 */
class SMTP_Mailer extends \NewsletterMailer {

	/**
	 * Batch size for bulk enqueuing.
	 *
	 * @var int
	 */
	protected $batch_size = 10;

	/**
	 * Constructor.
	 *
	 * @param array<string, mixed> $options Plugin options.
	 */
	public function __construct( $options = array() ) {
		parent::__construct( 'robotstxt-smtp-newsletter', $options );

		// Configure batch_size from turbo (standard Newsletter pattern).
		if ( ! empty( $options['turbo'] ) ) {
			$this->batch_size = max( 1, (int) $options['turbo'] );
		}
	}

	/**
	 * Get speed (emails per hour) for Newsletter engine.
	 *
	 * Standard Newsletter addons don't implement this, but we do
	 * to allow dynamic speed calculation based on rate limits.
	 *
	 * @return int
	 */
	public function get_speed() {
		return $this->speed;
	}

	/**
	 * Enqueue single email to database.
	 *
	 * @param \TNP_Mailer_Message $message Message to enqueue.
	 *
	 * @return bool|WP_Error True on success, WP_Error on failure.
	 */
	public function send( $message ) {
		$email    = Email_Message::from_newsletter_message( $message );
		$queue    = Queue::get_instance();
		$queue_id = $queue->enqueue( $email );

		if ( ! $queue_id ) {
			return new \WP_Error( self::ERROR_GENERIC, __( 'Failed to enqueue email', 'robotstxt-smtp-newsletter' ) );
		}

		return true;
	}

	/**
	 * Enqueue chunk of emails in bulk.
	 *
	 * @param array<\TNP_Mailer_Message> $messages Messages to enqueue.
	 *
	 * @return bool|WP_Error True on success, WP_Error on failure.
	 */
	public function send_chunk( $messages ) {
		$emails = array_map(
			array( Email_Message::class, 'from_newsletter_message' ),
			$messages
		);

		$queue     = Queue::get_instance();
		$queue_ids = $queue->enqueue_bulk( $emails );

		if ( count( $queue_ids ) !== count( $messages ) ) {
			return new \WP_Error(
				self::ERROR_GENERIC,
				sprintf(
					/* translators: %d: number of emails that failed to enqueue */
					__( '%d emails failed to enqueue', 'robotstxt-smtp-newsletter' ),
					count( $messages ) - count( $queue_ids )
				)
			);
		}

		return true;
	}

}