<?php
/**
 * Mail diagnostics: SMTP detection, test mail, recent failures.
 *
 * @package ALPEG\Forms
 */

namespace ALPEG\Forms;

defined( 'ABSPATH' ) || exit;

/**
 * Helps site owners understand why form mails do (not) arrive.
 */
class Mail_Diagnostics {

	/**
	 * Detect a configured SMTP / mail delivery plugin.
	 *
	 * @return string Name of the detected plugin, 'other' for an unknown hook or '' for none.
	 */
	public static function detect_smtp() {
		$known = array(
			'WP Mail SMTP'      => defined( 'WPMS_PLUGIN_VER' ),
			'FluentSMTP'        => defined( 'FLUENTMAIL' ) || defined( 'FLUENTMAIL_PLUGIN_VERSION' ),
			'Post SMTP'         => defined( 'POST_SMTP_VER' ),
			'Easy WP SMTP'      => defined( 'EasyWPSMTP_PLUGIN_VERSION' ) || class_exists( 'EasyWPSMTP' ),
			'SMTP Mailer'       => class_exists( 'SMTP_MAILER' ),
			'Brevo'             => class_exists( 'SIB_Manager' ),
			'Site Mailer'       => defined( 'SITE_MAILER_VERSION' ),
			'Gravity SMTP'      => defined( 'GRAVITY_SMTP_VERSION' ),
			'ALPEG Mail'        => defined( 'ALPEG_MAIL_VERSION' ),
		);
		foreach ( $known as $name => $active ) {
			if ( $active ) {
				return $name;
			}
		}
		if ( has_action( 'phpmailer_init' ) || has_filter( 'pre_wp_mail' ) ) {
			return 'other';
		}
		return '';
	}

	/**
	 * Last recorded mail error.
	 *
	 * @return array|null time, message.
	 */
	public static function last_error() {
		$e = get_option( 'alpeg_forms_last_mail_error' );
		return is_array( $e ) && ! empty( $e['message'] ) ? $e : null;
	}

	/**
	 * Number of entries in the last 7 days whose notification failed.
	 *
	 * @return int
	 */
	public static function recent_failures() {
		return Entries::count(
			array(
				'mail_status' => 'failed',
				'after'       => gmdate( 'Y-m-d H:i:s', time() - 7 * DAY_IN_SECONDS ),
			)
		);
	}

	/**
	 * Handle the "send test mail" form (admin-post).
	 */
	public static function handle_test() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'You are not allowed to do this.', 'alpeg-forms' ), 403 );
		}
		check_admin_referer( 'alpeg_forms_testmail' );
		$to = isset( $_POST['af_test_to'] ) ? sanitize_email( wp_unslash( $_POST['af_test_to'] ) ) : '';
		if ( ! is_email( $to ) ) {
			$notice = array(
				'type'    => 'error',
				'message' => __( 'Please enter a valid email address.', 'alpeg-forms' ),
			);
		} else {
			$r = Mailer::test( $to );
			if ( $r['ok'] ) {
				delete_option( 'alpeg_forms_last_mail_error' );
				$notice = array(
					'type'    => 'success',
					/* translators: %s: email address */
					'message' => sprintf( __( 'The test mail was handed over to the mail server for %s. Please check your inbox and spam folder.', 'alpeg-forms' ), $to ),
				);
			} else {
				$notice = array(
					'type'    => 'error',
					/* translators: %s: error message */
					'message' => sprintf( __( 'The test mail could not be sent: %s', 'alpeg-forms' ), $r['error'] ),
				);
			}
		}
		set_transient( 'alpeg_forms_settings_notice_' . get_current_user_id(), $notice, 60 );
		wp_safe_redirect( admin_url( 'admin.php?page=alpeg-forms-settings#mail' ) );
		exit;
	}
}