mailgun.php

<?php
/**
 * Plugin Name:  Mailgun
 * Plugin URI:   http://wordpress.org/extend/plugins/mailgun/
 * Description:  Mailgun integration for WordPress
 * Version:      2.2.3
 * Requires PHP: 7.4
 * Requires at least: 5.6
 * Author:       Mailgun
 * Author URI:   http://www.mailgun.com/
 * License:      GPLv2 or later
 * Text Domain:  mailgun
 * Domain Path:  /languages/.
 *
 * @package Mailgun
 */

/*
 * mailgun-wordpress-plugin - Sending mail from Wordpress using Mailgun
 * Copyright (C) 2016 Mailgun, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/**
 * Entrypoint for the Mailgun plugin. Sets up the mailing "strategy" -
 * either API or SMTP.
 *
 * Registers handlers for later actions and sets up config variables with
 * WordPress.
 */
class Mailgun {

    /**
     * @var Mailgun $instance
     */
    private static Mailgun $instance;

    /**
     * @var false|mixed|null
     */
    private $options;

    /**
     * @var string
     */
    protected string $plugin_file;

    /**
     * @var string
     */
    protected string $plugin_basename;

    /**
     * @var string
     */
    protected string $assetsDir;

    /**
     * @var string
     */
    private string $api_endpoint;

    /**
     * Setup shared functionality for Admin and Front End.
     */
    public function __construct() {
        $this->options         = get_option( 'mailgun' );
        $this->plugin_file     = __FILE__;
        $this->plugin_basename = plugin_basename( $this->plugin_file );
        $this->assetsDir       = plugin_dir_url( $this->plugin_file ) . 'assets/';

        // Either override the wp_mail function or configure PHPMailer to use the
        // Mailgun SMTP servers
        // When using SMTP, we also need to inject a `wp_mail` filter to make "from" settings
        // work properly. Fixed issues with 1.5.7+
        if ( $this->get_option( 'useAPI' ) || ( defined( 'MAILGUN_USEAPI' ) && MAILGUN_USEAPI ) ) {
            if ( ! function_exists( 'wp_mail' ) ) {
                if ( ! include_once __DIR__ . '/includes/wp-mail-api.php' ) {
                    $this->deactivate_and_die( __DIR__ . '/includes/wp-mail-api.php' );
                }
            }
        } else {
            // Using SMTP, include the SMTP filter
            if ( ! function_exists( 'mg_smtp_mail_filter' ) ) {
                if ( ! include __DIR__ . '/includes/wp-mail-smtp.php' ) {
                    $this->deactivate_and_die( __DIR__ . '/includes/wp-mail-smtp.php' );
                }
            }
            add_filter( 'wp_mail', 'mg_smtp_mail_filter' );
            add_action( 'phpmailer_init', array( &$this, 'phpmailer_init' ) );
            add_action( 'wp_mail_failed', 'wp_mail_failed' );
        }
    }

    /**
     * @return static
     */
    public static function getInstance(): Mailgun {
        if ( ! isset( self::$instance ) ) {
            self::$instance = new self();
        }

        return self::$instance;
    }

    /**
     * Get specific option from the options table.
     *
     * @param string     $option Name of option to be used as array key for retrieving the specific value
     * @param array|null $options Array to iterate over for specific values
     * @param bool       $defaultValue Default value to return if option is not found
     * @return    mixed
     */
    public function get_option( string $option, ?array $options = null, bool $defaultValue = false ) {
        if ( is_null( $options ) ) {
            $options = &$this->options;
        }

        if ( isset( $options[ $option ] ) ) {
            return $options[ $option ];
        }

        return $defaultValue;
    }

    /**
     * Hook into phpmailer to override SMTP based configurations
     * to use the Mailgun SMTP server.
     *
     * @param    object $phpmailer The PHPMailer object to modify by reference
     *
     * @return    void
     */
    public function phpmailer_init( &$phpmailer ): void {
        $username = ( defined( 'MAILGUN_USERNAME' ) && MAILGUN_USERNAME ) ? MAILGUN_USERNAME : $this->get_option( 'username' );
        $domain   = ( defined( 'MAILGUN_DOMAIN' ) && MAILGUN_DOMAIN ) ? MAILGUN_DOMAIN : $this->get_option( 'domain' );
        $username = preg_replace( '/@.+$/', '', $username ) . "@{$domain}";
        $secure   = ( defined( 'MAILGUN_SECURE' ) && MAILGUN_SECURE ) ? MAILGUN_SECURE : $this->get_option( 'secure' );
        $sectype  = ( defined( 'MAILGUN_SECTYPE' ) && MAILGUN_SECTYPE ) ? MAILGUN_SECTYPE : $this->get_option( 'sectype' );
        $password = ( defined( 'MAILGUN_PASSWORD' ) && MAILGUN_PASSWORD ) ? MAILGUN_PASSWORD : $this->get_option( 'password' );
        $region   = ( defined( 'MAILGUN_REGION' ) && MAILGUN_REGION ) ? MAILGUN_REGION : $this->get_option( 'region' );

        $smtp_endpoint = mg_smtp_get_region( $region );
        $smtp_endpoint = (bool) $smtp_endpoint ? $smtp_endpoint : 'smtp.mailgun.org';

        $phpmailer->Mailer = 'smtp';
        $phpmailer->Host   = $smtp_endpoint;

        if ( 'ssl' === $sectype ) {
            // For SSL-only connections, use 465
            $phpmailer->Port = 465;
        } else {
            // Otherwise, use 587.
            $phpmailer->Port = 587;
        }

        $phpmailer->SMTPAuth = true;
        $phpmailer->Username = $username;
        $phpmailer->Password = $password;

        $phpmailer->SMTPSecure = (bool) $secure ? $sectype : '';
        // Without this line... wp_mail for SMTP-only will always return false. But why? :(
        $phpmailer->Debugoutput = 'mg_smtp_debug_output';
        $phpmailer->SMTPDebug   = 2;

        // Emit some logging for SMTP connection
        mg_smtp_debug_output(
            sprintf( 'PHPMailer configured to send via %s:%s', $phpmailer->Host, $phpmailer->Port ),
            'DEBUG'
        );
    }

    /**
     * Deactivate this plugin and die.
     * Deactivate the plugin when files critical to it's operation cannot be loaded
     *
     * @param string $file files critical to plugin functionality
     *
     * @return    void
     */
    public function deactivate_and_die( $file ): void {
        load_plugin_textdomain( 'mailgun', false, 'mailgun/languages' );
        $message = sprintf(
            __( 'Mailgun has been automatically deactivated because the file <strong>%s</strong> is missing. Please reinstall the plugin and reactivate.' ),
            $file
        );
        if ( ! function_exists( 'deactivate_plugins' ) ) {
            include ABSPATH . 'wp-admin/includes/plugin.php';
        }
        deactivate_plugins( __FILE__ );
        wp_die( $message );
    }

    /**
     * Make a Mailgun api call.
     *
     * @param string $uri    The endpoint for the Mailgun API
     * @param array  $params Array of parameters passed to the API
     * @param string $method The form request type
     *
     * @return    string
     */
    public function api_call( string $uri, array $params = [], string $method = 'POST' ): string {
        $options   = get_option( 'mailgun' );
        $getRegion = ( defined( 'MAILGUN_REGION' ) && MAILGUN_REGION ) ? MAILGUN_REGION : $options['region'];
        $apiKey    = ( defined( 'MAILGUN_APIKEY' ) && MAILGUN_APIKEY ) ? MAILGUN_APIKEY : $options['apiKey'];
        $domain    = ( defined( 'MAILGUN_DOMAIN' ) && MAILGUN_DOMAIN ) ? MAILGUN_DOMAIN : $options['domain'];

        if ( ! function_exists( 'mg_api_get_region' ) ) {
            include __DIR__ . '/includes/mg-filter.php';
        }
        $region             = mg_api_get_region( $getRegion );
        $this->api_endpoint = ( $region ) ?: 'https://api.mailgun.net/v3/';

        $time    = time();
        $url     = $this->api_endpoint . $uri;
        $headers = [
            'Authorization' => 'Basic ' . base64_encode( "api:{$apiKey}" ),
        ];

        switch ( $method ) {
            case 'GET':
                $params['sess'] = '';
                $querystring    = http_build_query( $params );
                $url            = $url . '?' . $querystring;
                $params         = '';
                break;
            case 'POST':
            case 'PUT':
            case 'DELETE':
                $params['sess'] = '';
                $params['time'] = $time;
                $params['hash'] = hash( 'sha256', date( 'U' ) );
                break;
        }

        // make the request
        $args = [
            'method'    => $method,
            'body'      => $params,
            'headers'   => $headers,
            'sslverify' => true,
        ];

        // make the remote request
        $result = wp_remote_request( $url, $args );
        if ( ! is_wp_error( $result ) ) {
            return $result['body'];
        }

        if ( is_callable( $result ) ) {
            return $result->get_error_message();
        }

        if ( is_array( $result ) ) {
            if ( isset( $result['response'] ) ) {
                return $result['response']['message'] ?? '';
            }
        }

        return '';
    }

    /**
     * Get account associated lists.
     *
     * @return    array
     *
     * @throws JsonException
     */
    public function get_lists(): array {
        $results = [];

        $lists_json = $this->api_call( 'lists', [], 'GET' );

        $lists_arr = json_decode( $lists_json, true, 512, JSON_THROW_ON_ERROR );
        if ( isset( $lists_arr['items'] ) && ! empty( $lists_arr['items'] ) ) {
            $results = $lists_arr['items'];
        }

        return $results;
    }

    /**
     * @return array
     * @throws JsonException
     */
    public function getTrackingSettings(): array
    {
        $domain   = ( defined( 'MAILGUN_DOMAIN' ) && MAILGUN_DOMAIN ) ? MAILGUN_DOMAIN : $this->get_option( 'domain' );
        if (!$domain) {
            return [];
        }
        $settings = $this->api_call(sprintf("domains/%s/tracking", $domain), [], 'GET' );

        return json_decode( $settings, true, 512, JSON_THROW_ON_ERROR );
    }

    /**
     * Handle add list ajax post.
     *
     * @return    void    json
     *
     * @throws JsonException
     */
    public function add_list(): void {
        if ( ! isset( $_POST['mailgun_nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['mailgun_nonce'] ) ), 'mailgun_subscribe' ) ) {
            wp_send_json( [ 'status' => 403, 'message' => 'Invalid request.' ], 403 );
            return;
        }

        $name           = sanitize_text_field( $_POST['name'] ?? null );
        $email          = sanitize_text_field( $_POST['email'] ?? null );
        $list_addresses = [];

        $valid_lists = array_column( $this->get_lists(), 'address' );

        foreach ( ( $_POST['addresses'] ?? [] ) as $address => $val ) {
            $sanitized_address = sanitize_text_field( $address );
            if ( in_array( $sanitized_address, $valid_lists, true ) ) {
                $list_addresses[ $sanitized_address ] = sanitize_text_field( $val );
            }
        }

        if ( ! empty( $list_addresses ) ) {
            $result = [];
            foreach ( $list_addresses as $address => $val ) {
                $result[] = $this->api_call(
                    "lists/{$address}/members",
                    [
                        'address' => $email,
                        'name'    => $name,
                    ]
                );
            }
            $message = 'Thank you!';
            if ( $result ) {
                $message  = 'Something went wrong';
                $response = json_decode( $result[0], true );
                if ( is_array( $response ) && isset( $response['message'] ) ) {
                    $message = $response['message'];
                }
			}
            echo json_encode(
                [
					'status'  => 200,
					'message' => $message,
                ],
                JSON_THROW_ON_ERROR
            );
        } else {
            echo json_encode(
                [
					'status'  => 500,
					'message' => 'Uh oh. We weren\'t able to add you to the list' . count( $list_addresses ) ? 's.' : '. Please try again.',
                ],
                JSON_THROW_ON_ERROR
            );
        }
        wp_die();
    }

    /**
     * Frontend List Form.
     *
     * @param string $list_address Mailgun address list id
     * @param array  $args widget arguments
     * @throws JsonException
     */
    public function list_form( string $list_address, array $args = []): void {
        $widgetId        = $args['widget_id'] ?? 0;
        $widget_class_id = "mailgun-list-widget-{$widgetId}";
        $form_class_id   = "list-form-{$widgetId}";

        // List addresses from the plugin config
        $list_addresses = array_map( 'trim', explode( ',', $list_address ) );

        // All list info from the API; used for list info when more than one list is available to subscribe to
        $all_list_addresses = $this->get_lists();
		?>
        <div class="mailgun-list-widget-front <?php echo esc_attr( $widget_class_id ); ?> widget">
            <form class="list-form <?php echo esc_attr( $form_class_id ); ?>">
                <div class="mailgun-list-widget-inputs">
                    <?php if ( isset( $args['list_title'] ) ) : ?>
                        <div class="mailgun-list-title">
                            <h4 class="widget-title">
                                <span><?php echo wp_kses_data( $args['list_title'] ); ?></span>
                            </h4>
                        </div>
                    <?php endif; ?>
                    <?php if ( isset( $args['list_description'] ) ) : ?>
                        <div class="mailgun-list-description">
                            <p class="widget-description">
                                <span><?php echo wp_kses_data( $args['list_description'] ); ?></span>
                            </p>
                        </div>
                    <?php endif; ?>
                    <?php if ( isset( $args['collect_name'] ) && (int) $args['collect_name'] === 1 ) : ?>
                        <p class="mailgun-list-widget-name">
                            <label><strong>Name:</strong></label>
                            <input type="text" name="name" placeholder="Name"/>
                        </p>
                    <?php endif; ?>
                    <p class="mailgun-list-widget-email">
                        <label><strong>Email:</strong></label>
                        <input type="text" name="email" placeholder="Email"/>
                    </p>
                </div>

                <div class="mailgun-list-widget-lists">
                    <?php if ( count( $list_addresses ) > '1' ) : ?>
                    <ul class="mailgun-lists" style="list-style: none;">
                        <?php
						foreach ( $all_list_addresses as $la ) :
							if ( ! in_array( $la['address'], $list_addresses, true ) ) :
								continue;
                                endif;
							?>
                                <li>
                                    <input type="checkbox" class="mailgun-list-name"
                                            name="addresses[<?php echo esc_attr( $la['address'] ); ?>]"/> <?php echo esc_attr( $la['name'] ?: $la['address'] ); ?>
                                </li>
                        <?php endforeach; ?>
                    </ul>
                <?php else : ?>
                    <input type="hidden" name="addresses[<?php echo esc_attr( $list_addresses[0] ); ?>]" value="on"/>
                <?php endif; ?>

                <input class="mailgun-list-submit-button" data-form-id="<?php echo esc_attr( $form_class_id ); ?>" type="button"
                        value="Subscribe"/>
                <input type="hidden" name="mailgun-submission" value="1"/>
                <?php wp_nonce_field( 'mailgun_subscribe', 'mailgun_nonce' ); ?></div>

            </form>
            <div class="widget-list-panel result-panel" style="display:none;">
                <span>Thank you for subscribing!</span>
            </div>
        </div>

        <script>
            jQuery(document).ready(function () {

            jQuery('.mailgun-list-submit-button').on('click', function () {

                var form_id = jQuery(this).data('form-id')

                if (jQuery('.mailgun-list-name').length > 0 && jQuery('.' + form_id + ' .mailgun-list-name:checked').length < 1) {
                alert('Please select a list to subscribe to.')
                return
                }

                if (jQuery('.' + form_id + ' .mailgun-list-widget-name input') && jQuery('.' + form_id + ' .mailgun-list-widget-name input').val() === '') {
                alert('Please enter your subscription name.')
                return
                }

                if (jQuery('.' + form_id + ' .mailgun-list-widget-email input').val() === '') {
                alert('Please enter your subscription email.')
                return
                }

              // Email validation regex pattern
              var emailPattern = /.+@.+\..{2,}/;

              if (!emailPattern.test(jQuery('.' + form_id + ' .mailgun-list-widget-email input').val())) {
                  alert('Please enter a valid email address.')
                  return
              }

                jQuery.ajax({
                url: '<?php echo admin_url( 'admin-ajax.php?action=add_list' ); ?>',
                action: 'add_list',
                type: 'post',
                dataType: 'json',
                data: jQuery('.' + form_id + '').serialize(),
                success: function (data) {
                    data_msg = data.message
                    already_exists = false
                    if (data_msg !== undefined) {
                    already_exists = data_msg.indexOf('Address already exists') > -1
                    }

                    // success
                    if ((data.status === 200)) {
                    jQuery('.<?php echo esc_attr( $widget_class_id ); ?> .widget-list-panel').css('display', 'none')
                    jQuery('.<?php echo esc_attr( $widget_class_id ); ?> .list-form').css('display', 'none')
                    jQuery('.<?php echo esc_attr( $widget_class_id ); ?> .result-panel').css('display', 'block')
                    // error
                    } else {
                    alert(data_msg)
                    }
                }
                })
            })
            })
        </script>

        <?php
    }

    /**
     * Initialize List Form.
     *
     * @param array $atts Form attributes
     *
     * @return    string
     *
     * @throws JsonException
     */
    public function build_list_form( array $atts ): string {
        if ( isset( $atts['id'] ) && $atts['id'] !== '' ) {
            $args['widget_id'] = hash( 'sha256', rand( 10000, 99999 ) . $atts['id'] );

            if (isset( $atts['collect_name'] ) ) {
                $args['collect_name'] = true;
            }

            if (isset( $atts['title'] ) ) {
                $args['list_title'] = $atts['title'];
            }

            if (isset( $atts['description'] ) ) {
                $args['list_description'] = $atts['description'];
            }

            ob_start();
            $this->list_form( $atts['id'], $args );
            return ob_get_clean();
        }

        return '<span>Mailgun list ID needed to render form!</span>
        <br/>
        <strong>Example :</strong> [mailgun id="[your list id]"]';
    }

    /**
     * Initialize List Widget.
     */
    public function load_list_widget() {
        register_widget( 'List_Widget' );
        add_shortcode( 'mailgun', array( &$this, 'build_list_form' ) );
    }

    /**
     * @return string
     */
    public function getAssetsPath(): string {
        return $this->assetsDir;
    }
}

$mailgun = Mailgun::getInstance();

if (include __DIR__ . '/includes/widget.php' ) {
    add_action('widgets_init', array( &$mailgun, 'load_list_widget' ));
    add_action('wp_ajax_nopriv_add_list', array( &$mailgun, 'add_list' ));
    add_action('wp_ajax_add_list', array( &$mailgun, 'add_list' ));
}

if (is_admin()) {
    if (include __DIR__ . '/includes/admin.php') {
        $mailgunAdmin = new MailgunAdmin();
    } else {
        $mailgun->deactivate_and_die(__DIR__ . '/includes/admin.php');
    }
}