<?php
/** no direct access **/
defined('MECEXEC') or die();

/**
 * Webnus MEC notifications class
 * @author Webnus <info@webnus.net>
 */
class MEC_notifications extends MEC_base
{
    public $main;
    public $PT;
    public $notif_settings;
    public $settings;
    public $styling;
    public $book;
    public $u;

    /**
     * Constructor method
     * @author Webnus <info@webnus.net>
     */
    public function __construct()
    {
        // Import MEC Main
        $this->main = $this->getMain();

        // MEC Book Post Type Name
        $this->PT = $this->main->get_book_post_type();

        // MEC Notification Settings
        $this->notif_settings = $this->main->get_notifications();

        // MEC Settings
        $this->settings = $this->main->get_settings();

        // Styling
        $this->styling = $this->main->get_styling();

        // MEC Book
        $this->book = $this->getBook();

        // MEC User
        $this->u = $this->getUser();
    }

    /**
     * Send email verification notification
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @param string $mode
     * @return boolean
     */
    public function email_verification($book_id, $mode = 'auto')
    {
        if(!$book_id) return false;

        $booker = $this->u->booking($book_id);
        if(!isset($booker->user_email)) return false;

        $verification_status = get_post_meta($book_id, 'mec_verified', true);
        if($verification_status == 1) return false; // Already Verified

        $price = get_post_meta($book_id, 'mec_price', true);

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        list($auto_verify_free, $auto_verify_paid) = $this->book->get_auto_verification_status($event_id, $book_id);

        // Auto verification for free bookings is enabled so don't send the verification email
        if($mode == 'auto' and $price <= 0 and $auto_verify_free) return false;

        // Auto verification for paid bookings is enabled so don't send the verification email
        if($mode == 'auto' and $price > 0 and $auto_verify_paid) return false;

        $subject = isset($this->notif_settings['email_verification']['subject']) ? esc_html__($this->notif_settings['email_verification']['subject'], 'mec') : esc_html__('Please verify your email.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'email_verification', $event_id, $book_id), $book_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['email_verification']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['email_verification']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['email_verification']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Attendees
        $attendees = get_post_meta($book_id, 'mec_attendees', true);
        if(!is_array($attendees) or !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

        // Do not send email twice!
        $done_emails = [];

        // Book Data
        $key = get_post_meta($book_id, 'mec_verification_key', true);
        $link = trim(get_permalink($event_id), '/').'/verify/'.$key.'/';

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the emails
        foreach($attendees as $attendee)
        {
            $to = $attendee['email'] ?? '';
            if(!trim($to) or in_array($to, $done_emails) or !filter_var($to, FILTER_VALIDATE_EMAIL)) continue;

            $message = $this->notif_settings['email_verification']['content'] ?? '';
            $message = $this->content($this->get_content($message, 'email_verification', $event_id, $book_id), $book_id, $attendee);

            $message = str_replace('%%verification_link%%', $link, $message);
            $message = str_replace('%%link%%', $link, $message);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $to,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_email_verification', $mail_arg, $book_id, 'email_verification');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            // For prevention of email repeat send
            $done_emails[] = $to;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        return true;
    }

    /**
     * Send booking notification
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @return boolean
     */
    public function booking_notification($book_id)
    {
        if(!$book_id) return false;

        $booking_notification = apply_filters('mec_booking_notification', true);
        if(!$booking_notification) return false;

        $booker = $this->u->booking($book_id);
        if(!isset($booker->user_email)) return false;

        // Booking Notification is disabled
        if(isset($this->notif_settings['booking_notification']['status']) and !$this->notif_settings['booking_notification']['status']) return false;

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $subject = isset($this->notif_settings['booking_notification']['subject']) ? esc_html__($this->notif_settings['booking_notification']['subject'], 'mec') : esc_html__('Your booking is received.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'booking_notification', $event_id, $book_id), $book_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['booking_notification']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['booking_notification']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['booking_notification']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Send the notification to event organizer
        if(isset($this->notif_settings['booking_notification']['send_to_organizer']) and $this->notif_settings['booking_notification']['send_to_organizer'] == 1)
        {
            $organizer_email = $this->get_booking_organizer_email($book_id);
            if($organizer_email !== false) $headers[] = $CCBCC.': '.trim($organizer_email);
        }

        // Send the notification to additional organizers
        if(isset($this->notif_settings['booking_notification']['send_to_additional_organizers']) and $this->notif_settings['booking_notification']['send_to_additional_organizers'] == 1)
        {
            $additional_organizer_emails = $this->get_booking_additional_organizers_emails($book_id);
            if(is_array($additional_organizer_emails) and count($additional_organizer_emails))
            {
                foreach($additional_organizer_emails as $additional_organizer_email) $headers[] = $CCBCC.': '.trim($additional_organizer_email);
            }
        }

        // Attendees
        $attendees = get_post_meta($book_id, 'mec_attendees', true);
        if(!is_array($attendees) or !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

        // Do not send email twice!
        $done_emails = [];

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the emails
        foreach($attendees as $attendee)
        {
            $to = $attendee['email'] ?? '';
            if(!trim($to) or in_array($to, $done_emails) or !filter_var($to, FILTER_VALIDATE_EMAIL)) continue;

            $message = $this->notif_settings['booking_notification']['content'] ?? '';
            $message = $this->content($this->get_content($message, 'booking_notification', $event_id, $book_id), $book_id, $attendee);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $to,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_booking_notification', $mail_arg, $book_id, 'booking_notification');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            // For prevention of email repeat send
            $done_emails[] = $to;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        return true;
    }

    /**
     * Send booking confirmation notification
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @param string $mode
     * @return boolean
     */
    public function booking_confirmation($book_id, $mode = 'manually')
    {
        if(!$book_id) return false;

        // Booking Confirmation is disabled
        if(isset($this->notif_settings['booking_confirmation']['status']) and !$this->notif_settings['booking_confirmation']['status']) return false;

        $confirmation_notification = apply_filters('mec_booking_confirmation', true);
        if(!$confirmation_notification) return false;

        $booker = $this->u->booking($book_id);
        if(!isset($booker->user_email)) return false;

        $send_in_automode = isset($this->settings['booking_auto_confirm_send_email']) && $this->settings['booking_auto_confirm_send_email'] == '1';

        // Don't send the confirmation email
        if($mode == 'auto' and !$send_in_automode) return false;

        $timestamp = time();

        $last_confirmation_email = get_post_meta($book_id, 'mec_last_confirmation_email', true);
        if($last_confirmation_email and is_numeric($last_confirmation_email) and ($timestamp - $last_confirmation_email) < 10) return false;

        update_post_meta($book_id, 'mec_last_confirmation_email', $timestamp);

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $subject = isset($this->notif_settings['booking_confirmation']['subject']) ? esc_html__($this->notif_settings['booking_confirmation']['subject'], 'mec') : esc_html__('Your booking is confirmed.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'booking_confirmation', $event_id, $book_id), $book_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['booking_confirmation']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['booking_confirmation']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['booking_confirmation']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Attendees
        $attendees = get_post_meta($book_id, 'mec_attendees', true);
        if(!is_array($attendees) || !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

        // Do not send email twice!
        $done_emails = [];

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the emails
        foreach($attendees as $attendee)
        {
            $to = $attendee['email'] ?? '';

            if(!trim($to)) continue;
            if(in_array($to, $done_emails) or !filter_var($to, FILTER_VALIDATE_EMAIL)) continue;

            $message = $this->notif_settings['booking_confirmation']['content'] ?? '';
            $message = $this->content($this->get_content($message, 'booking_confirmation', $event_id, $book_id), $book_id, $attendee);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $to,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_booking_confirmation', $mail_arg, $book_id, 'booking_confirmation');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            // Send One Single Email Only To First Attendee
            if(isset($this->notif_settings['booking_confirmation']['send_single_one_email'])) break;

            // For prevention of email repeat send
            $done_emails[] = $to;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        return true;
    }

    /**
     * Send booking cancellation
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @return void
     */
    public function booking_cancellation($book_id)
    {
        if(!$book_id) return;

        $cancellation_notification = apply_filters('mec_booking_cancellation', true);
        if(!$cancellation_notification) return;

        $booker = $this->u->booking($book_id);

        // Cancelling Notification is disabled
        if(!isset($this->notif_settings['cancellation_notification']['status']) or (isset($this->notif_settings['cancellation_notification']['status']) and !$this->notif_settings['cancellation_notification']['status'])) return;

        $tos = [];

        // Send the notification to admin
        if(isset($this->notif_settings['cancellation_notification']['send_to_admin']) and $this->notif_settings['cancellation_notification']['send_to_admin'] == 1)
        {
            $tos[] = get_bloginfo('admin_email');
        }

        // Send the notification to event organizer
        if(isset($this->notif_settings['cancellation_notification']['send_to_organizer']) and $this->notif_settings['cancellation_notification']['send_to_organizer'] == 1)
        {
            $organizer_email = $this->get_booking_organizer_email($book_id);
            if($organizer_email !== false) $tos[] = trim($organizer_email);
        }

        // Send the notification to additional organizers
        if(isset($this->notif_settings['cancellation_notification']['send_to_additional_organizers']) and $this->notif_settings['cancellation_notification']['send_to_additional_organizers'] == 1)
        {
            $additional_organizer_emails = $this->get_booking_additional_organizers_emails($book_id);
            if(is_array($additional_organizer_emails) and count($additional_organizer_emails))
            {
                foreach($additional_organizer_emails as $additional_organizer_email) $tos[] = trim($additional_organizer_email);
            }
        }

        // Send the notification to event user
        if(isset($this->notif_settings['cancellation_notification']['send_to_user']) and $this->notif_settings['cancellation_notification']['send_to_user'] == 1)
        {
            if(isset($booker->user_email) and $booker->user_email)
            {
                // Attendees
                $attendees = get_post_meta($book_id, 'mec_attendees', true);
                if(!is_array($attendees) or (is_array($attendees) and !count($attendees))) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

                // Prevent duplicate send
                $done_emails = [];

                // Send the emails
                foreach($attendees as $attendee)
                {
                    if(isset($attendee['email']) and !in_array($attendee['email'], $done_emails))
                    {
                        $tos[] = $attendee;
                        $done_emails[] = $attendee['email'];
                    }
                }
            }
        }

        // No Recipient
        if(!count($tos)) return;

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['cancellation_notification']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['cancellation_notification']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['cancellation_notification']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $subject = isset($this->notif_settings['cancellation_notification']['subject']) ? esc_html__($this->notif_settings['cancellation_notification']['subject'], 'mec') : esc_html__('booking canceled.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'cancellation_notification', $event_id, $book_id), $book_id);

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the mail
        $i = 1;
        foreach($tos as $to)
        {
            $mailto = (is_array($to) and isset($to['email'])) ? $to['email'] : $to;

            if(!trim($mailto) or !filter_var($mailto, FILTER_VALIDATE_EMAIL)) continue;
            if($i > 1) $headers = array('Content-Type: text/html; charset=UTF-8');

            $message = $this->notif_settings['cancellation_notification']['content'] ?? '';
            $message = $this->content($this->get_content($message, 'cancellation_notification', $event_id, $book_id), $book_id, (is_array($to) ? $to : NULL));

            // Book Data
            $message = str_replace('%%admin_link%%', $this->link(array('post_type'=>$this->main->get_book_post_type()), $this->main->URL('admin').'edit.php'), $message);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $mailto,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_booking_cancellation', $mail_arg, $book_id, 'booking_cancellation');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            $i++;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));
    }

    /**
     * Send booking rejection
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @return void
     */
    public function booking_rejection($book_id)
    {
        if(!$book_id) return;

        $rejection_notification = apply_filters('mec_booking_rejection', true);
        if(!$rejection_notification) return;

        $booker = $this->u->booking($book_id);

        // Rejection Notification is disabled
        if(!isset($this->notif_settings['booking_rejection']['status']) or (isset($this->notif_settings['booking_rejection']['status']) and !$this->notif_settings['booking_rejection']['status'])) return;

        $tos = [];

        // Send the notification to admin
        if(isset($this->notif_settings['booking_rejection']['send_to_admin']) and $this->notif_settings['booking_rejection']['send_to_admin'] == 1)
        {
            $tos[] = get_bloginfo('admin_email');
        }

        // Send the notification to event organizer
        if(isset($this->notif_settings['booking_rejection']['send_to_organizer']) and $this->notif_settings['booking_rejection']['send_to_organizer'] == 1)
        {
            $organizer_email = $this->get_booking_organizer_email($book_id);
            if($organizer_email !== false) $tos[] = trim($organizer_email);
        }

        // Send the notification to additional organizers
        if(isset($this->notif_settings['booking_rejection']['send_to_additional_organizers']) and $this->notif_settings['booking_rejection']['send_to_additional_organizers'] == 1)
        {
            $additional_organizer_emails = $this->get_booking_additional_organizers_emails($book_id);
            if(is_array($additional_organizer_emails) and count($additional_organizer_emails))
            {
                foreach($additional_organizer_emails as $additional_organizer_email) $tos[] = trim($additional_organizer_email);
            }
        }

        // Send the notification to event user
        if(isset($this->notif_settings['booking_rejection']['send_to_user']) and $this->notif_settings['booking_rejection']['send_to_user'] == 1)
        {
            if(isset($booker->user_email) and $booker->user_email)
            {
                // Attendees
                $attendees = get_post_meta($book_id, 'mec_attendees', true);
                if(!is_array($attendees) or !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

                // Prevent duplicate send
                $done_emails = [];

                // Send the emails
                foreach($attendees as $attendee)
                {
                    if(isset($attendee['email']) and !in_array($attendee['email'], $done_emails))
                    {
                        $tos[] = $attendee;
                        $done_emails[] = $attendee['email'];
                    }
                }
            }
        }

        // No Recipient
        if(!count($tos)) return;

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['booking_rejection']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['booking_rejection']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['booking_rejection']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $subject = isset($this->notif_settings['booking_rejection']['subject']) ? esc_html__($this->notif_settings['booking_rejection']['subject'], 'mec') : esc_html__('booking rejected.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'booking_rejection', $event_id, $book_id), $book_id);

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the mail
        $i = 1;
        foreach($tos as $to)
        {
            $mailto = (is_array($to) and isset($to['email'])) ? $to['email'] : $to;

            if(!trim($mailto) or !filter_var($mailto, FILTER_VALIDATE_EMAIL)) continue;
            if($i > 1) $headers = array('Content-Type: text/html; charset=UTF-8');

            $message = $this->notif_settings['booking_rejection']['content'] ?? '';
            $message = $this->content($this->get_content($message, 'booking_rejection', $event_id, $book_id), $book_id, (is_array($to) ? $to : NULL));

            // Book Data
            $message = str_replace('%%admin_link%%', $this->link(array('post_type'=>$this->main->get_book_post_type()), $this->main->URL('admin').'edit.php'), $message);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $mailto,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_booking_rejection', $mail_arg, $book_id, 'booking_rejection');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            $i++;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));
    }

    /**
     * Send admin notification
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @return void
     */
    public function admin_notification($book_id)
    {
        if(!$book_id) return;

        // Admin Notification is disabled
        if(isset($this->notif_settings['admin_notification']['status']) and !$this->notif_settings['admin_notification']['status']) return;

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $to = get_bloginfo('admin_email');
        $subject = isset($this->notif_settings['admin_notification']['subject']) ? esc_html__($this->notif_settings['admin_notification']['subject'], 'mec') : esc_html__('A new booking is received.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'admin_notification', $event_id, $book_id), $book_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['admin_notification']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['admin_notification']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['admin_notification']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Don't send the email to admin
        if(isset($this->notif_settings['admin_notification']['send_to_admin']) and !$this->notif_settings['admin_notification']['send_to_admin'])
        {
            if(is_array($recipients) and count($recipients))
            {
                $to = current($recipients);
                unset($recipients[0]);
            }
            elseif(isset($this->notif_settings['admin_notification']['send_to_organizer']) and $this->notif_settings['admin_notification']['send_to_organizer'] == 1)
            {
                $organizer_email = $this->get_booking_organizer_email($book_id);
                if($organizer_email !== false) $to = $organizer_email;
            }
            else return;
        }

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Send the notification to event organizer
        if(isset($this->notif_settings['admin_notification']['send_to_organizer']) and $this->notif_settings['admin_notification']['send_to_organizer'] == 1)
        {
            $organizer_email = $this->get_booking_organizer_email($book_id);
            if($organizer_email !== false and $organizer_email != $to) $headers[] = $CCBCC.': '.trim($organizer_email);
        }

        // Send the notification to additional organizers
        if(isset($this->notif_settings['admin_notification']['send_to_additional_organizers']) and $this->notif_settings['admin_notification']['send_to_additional_organizers'] == 1)
        {
            $additional_organizer_emails = $this->get_booking_additional_organizers_emails($book_id);
            if(is_array($additional_organizer_emails) and count($additional_organizer_emails))
            {
                foreach($additional_organizer_emails as $additional_organizer_email)
                {
                    if($additional_organizer_email != $to) $headers[] = $CCBCC.': '.trim($additional_organizer_email);
                }
            }
        }

        $message = $this->notif_settings['admin_notification']['content'] ?? '';
        $message = $this->content($this->get_content($message, 'admin_notification', $event_id, $book_id), $book_id);

        // Book Data
        $message = str_replace('%%admin_link%%', $this->link(array('post_type'=>$this->main->get_book_post_type()), $this->main->URL('admin').'edit.php'), $message);

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Remove remained placeholders
        $message = preg_replace('/%%.*%%/', '', $message);

        $message = $this->add_template($message);

        // Filter the email
        $mail_arg = array(
            'to'            => $to,
            'subject'       => $subject,
            'message'       => $message,
            'headers'       => $headers,
            'attachments'   => array(),
        );

        $mail_arg = apply_filters('mec_before_send_admin_notification', $mail_arg, $book_id, 'admin_notification');

        // Send the mail
        wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));
    }

    /**
     * Send booking reminder notification
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @param string $timestamps
     * @return boolean
     */
    public function booking_reminder($book_id, $timestamps = NULL)
    {
        if(!$book_id) return false;

        $booker = $this->u->booking($book_id);
        if(!isset($booker->user_email)) return false;

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $subject = isset($this->notif_settings['booking_reminder']['subject']) ? esc_html__($this->notif_settings['booking_reminder']['subject'], 'mec') : esc_html__('Booking Reminder', 'mec');
        $subject = $this->content($this->get_subject($subject, 'booking_reminder', $event_id, $book_id), $book_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['booking_reminder']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['booking_reminder']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['booking_reminder']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Attendees
        $attendees = get_post_meta($book_id, 'mec_attendees', true);
        if(!is_array($attendees) or !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

        // Do not send email twice!
        $done_emails = [];

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the emails
        foreach($attendees as $attendee)
        {
            if(isset($attendee[0]['MEC_TYPE_OF_DATA'])) continue;

            $to = $attendee['email'] ?? '';

            if(!trim($to)) continue;
            if(in_array($to, $done_emails) or !filter_var($to, FILTER_VALIDATE_EMAIL)) continue;

            $message = $this->notif_settings['booking_reminder']['content'] ?? '';

            $message = str_replace('%%zoom_join%%', get_post_meta($event_id, 'mec_zoom_join_url', true), $message);
            $message = str_replace('%%zoom_link%%', get_post_meta($event_id, 'mec_zoom_link_url', true), $message);
            $message = str_replace('%%zoom_password%%', get_post_meta($event_id, 'mec_zoom_password', true), $message);
            $message = str_replace('%%zoom_embed%%', get_post_meta($event_id, 'mec_zoom_embed', true), $message);

            $message = $this->content($this->get_content($message, 'booking_reminder', $event_id, $book_id), $book_id, $attendee, $timestamps);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $to,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_booking_reminder', $mail_arg, $book_id, 'booking_reminder');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            $done_emails[] = $to;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        return true;
    }

    /**
     * Send new event notification
     * @author Webnus <info@webnus.net>
     * @param int $event_id
     * @param boolean $update
     * @return boolean
     */
    public function new_event($event_id, $update = false)
    {
        if(!$event_id) return false;

        // If this is an autosave, our form has not been submitted, so we don't want to do anything.
        if(defined('DOING_AUTOSAVE') and DOING_AUTOSAVE) return false;

        // MEC Event Post Type
        $event_PT = $this->main->get_main_post_type();

        // If it's not a MEC Event
        if(get_post_type($event_id) != $event_PT) return false;

        // If it's an update request, then don't send any notification
        if($update) return false;

        // New event notification is disabled
        if(!isset($this->notif_settings['new_event']['status']) or (isset($this->notif_settings['new_event']['status']) and !$this->notif_settings['new_event']['status'])) return false;

        $status = get_post_status($event_id);

        // Don't send the email if it is draft or an auto draft post
        if($status == 'auto-draft' or $status == 'draft') return false;

        $already_sent = get_post_meta($event_id, 'mec_new_event_notif_sent', true);
        if($already_sent) return false;

        $to = (!isset($this->notif_settings['new_event']['send_to_admin']) or (isset($this->notif_settings['new_event']['send_to_admin']) and $this->notif_settings['new_event']['send_to_admin'])) ? get_bloginfo('admin_email') : NULL;

        $disabled_send_notification_if_current_user_or_author_is_superadmin = isset($this->notif_settings['new_event']['disable_send_notification_if_current_user_or_author_is_admin']) and $this->notif_settings['new_event']['disable_send_notification_if_current_user_or_author_is_admin'] ? true : false;
        if($disabled_send_notification_if_current_user_or_author_is_superadmin && current_user_can('manage_options')) $to = NULL;

        $recipients_str = $this->notif_settings['new_event']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['new_event']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['new_event']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        if(is_null($to) and !count($recipients)) return false;
        else if(is_null($to))
        {
            $to = current($recipients);
            unset($recipients[0]);
        }

        $subject = (isset($this->notif_settings['new_event']['subject']) and trim($this->notif_settings['new_event']['subject'])) ? esc_html__($this->notif_settings['new_event']['subject'], 'mec') : esc_html__('A new event is added.', 'mec');
        $subject = $this->get_subject($subject, 'new_event', $event_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Date Format
        $date_format = get_option('date_format');

        $message = (isset($this->notif_settings['new_event']['content']) and trim($this->notif_settings['new_event']['content'])) ? $this->notif_settings['new_event']['content'] : '';
        $message = $this->get_content($message, 'new_event', $event_id);

        // Site Data
        $message = str_replace('%%blog_name%%', get_bloginfo('name'), $message);
        $message = str_replace('%%blog_url%%', get_bloginfo('url'), $message);
        $message = str_replace('%%blog_description%%', get_bloginfo('description'), $message);

        // Event Data
        $message = str_replace('%%admin_link%%', $this->link(array('post_type'=>$event_PT), $this->main->URL('admin').'edit.php'), $message);
        $message = str_replace('%%event_title%%', get_the_title($event_id), $message);
        $message = str_replace('%%event_link%%', get_post_permalink($event_id), $message);
        $message = str_replace('%%event_description%%', strip_tags(strip_shortcodes(get_post_field('post_content', $event_id))), $message);

        $event_tags = get_the_terms($event_id, apply_filters('mec_taxonomy_tag', ''));
        $message = str_replace('%%event_tags%%', (is_array($event_tags) ? join(', ', wp_list_pluck($event_tags, 'name')) : ''), $message);

        $event_labels = get_the_terms($event_id, 'mec_label');
        $message = str_replace('%%event_labels%%', (is_array($event_labels) ? join(', ', wp_list_pluck($event_labels, 'name')) : ''), $message);

        $event_categories = get_the_terms($event_id, 'mec_category');
        $message = str_replace('%%event_categories%%', (is_array($event_categories) ? join(', ', wp_list_pluck($event_categories, 'name')) : ''), $message);

        $mec_cost = get_post_meta($event_id, 'mec_cost', true);
        $message = str_replace('%%event_cost%%', (is_numeric($mec_cost) ? $this->main->render_price($mec_cost, $event_id) : $mec_cost), $message);

        $message = str_replace('%%event_start_date%%', $this->main->date_i18n($date_format, strtotime(get_post_meta($event_id, 'mec_start_date', true))), $message);
        $message = str_replace('%%event_end_date%%', $this->main->date_i18n($date_format, strtotime(get_post_meta($event_id, 'mec_end_date', true))), $message);
        $message = str_replace('%%event_timezone%%', $this->main->get_timezone($event_id), $message);
        $message = str_replace('%%event_note%%', get_post_meta($event_id, 'mec_note', true), $message);

        $status_obj = get_post_status_object($status);
        $message = str_replace('%%event_status%%', (($status_obj and isset($status_obj->label)) ? $status_obj->label : $status), $message);

        // Data Fields
        $event_fields = $this->main->get_event_fields();
        $event_fields_data = get_post_meta($event_id, 'mec_fields', true);
        if(!is_array($event_fields_data)) $event_fields_data = [];

        foreach($event_fields as $f => $event_field)
        {
            if(!is_numeric($f)) continue;

            $field_value = $event_fields_data[$f] ?? '';
            if((!is_array($field_value) and trim($field_value) === '') or (is_array($field_value) and !count($field_value)))
            {
                $message = str_replace('%%event_field_'.$f.'%%', '', $message);
                $message = str_replace('%%event_field_'.$f.'_with_name%%', '', $message);

                continue;
            }

            $event_field_name = $event_field['label'] ?? '';
            if(is_array($field_value)) $field_value = implode(', ', $field_value);

            $message = str_replace('%%event_field_'.$f.'%%', trim($field_value, ', '), $message);
            $message = str_replace('%%event_field_'.$f.'_with_name%%', trim((trim($event_field_name) ? $event_field_name.': ' : '').trim($field_value, ', ')), $message);
        }

        $message = str_replace('%%zoom_join%%', get_post_meta($event_id, 'mec_zoom_join_url', true), $message);
        $message = str_replace('%%zoom_link%%', get_post_meta($event_id, 'mec_zoom_link_url', true), $message);
        $message = str_replace('%%zoom_password%%', get_post_meta($event_id, 'mec_zoom_password', true), $message);
        $message = str_replace('%%zoom_embed%%', get_post_meta($event_id, 'mec_zoom_embed', true), $message);

        // Remove remained placeholders
        $message = preg_replace('/%%.*%%/', '', $message);

        // Notification Subject
        $subject = str_replace('%%event_title%%', get_the_title($event_id), $subject);

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the mail
        wp_mail($to, html_entity_decode(stripslashes($subject), ENT_HTML5), wpautop(stripslashes($message)), $headers);

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        update_post_meta($event_id, 'mec_new_event_notif_sent', 1);

        return true;
    }

   /**
    * Send new event published notification
    * @author Webnus <info@webnus.net>
    * @param string $new
    * @param string $old
    * @param WP_Post $post
    * @return boolean
    */
    public function user_event_publishing($new, $old, $post)
    {
        // MEC Event Post Type
        $event_PT = $this->main->get_main_post_type();

        // User event publishing notification is disabled
        if(!isset($this->notif_settings['user_event_publishing']['status']) or (isset($this->notif_settings['user_event_publishing']['status']) and !$this->notif_settings['user_event_publishing']['status'])) return false;

        if(($new == 'publish') and ($old != 'publish') and ($post->post_type == $event_PT))
        {
            $email = get_post_meta($post->ID, 'fes_guest_email', true);
            $owner = get_userdata($post->post_author);

            // Not Set Guest User Email
            if(!trim($email) or !filter_var($email, FILTER_VALIDATE_EMAIL))
            {
                $email = (is_object($owner) ? $owner->user_email : '');
            }

            if(!trim($email) or !filter_var($email, FILTER_VALIDATE_EMAIL)) return false;

            $guest_name = get_post_meta($post->ID, 'fes_guest_name', true);
            if(!trim($guest_name)) $guest_name = $owner->first_name.' '.$owner->last_name;

            $status = get_post_status($post->ID);

            $to = $email;
            $subject = (isset($this->notif_settings['user_event_publishing']['subject']) and trim($this->notif_settings['user_event_publishing']['subject'])) ? esc_html__($this->notif_settings['user_event_publishing']['subject'], 'mec') : esc_html__('Your event is published.', 'mec');
            $subject = $this->get_subject($subject, 'user_event_publishing', $post->ID);

            $headers = array('Content-Type: text/html; charset=UTF-8');

            $recipients_str = $this->notif_settings['user_event_publishing']['recipients'] ?? '';
            $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

            $users = $this->notif_settings['user_event_publishing']['receiver_users'] ?? [];
            $users_down = $this->main->get_emails_by_users($users);
            $recipients = array_merge($users_down, $recipients);

            $roles = $this->notif_settings['user_event_publishing']['receiver_roles'] ?? [];
            $user_roles = $this->main->get_emails_by_roles($roles);
            $recipients = array_merge($user_roles, $recipients);

            // Unique Recipients
            $recipients = array_map('trim', $recipients);
            $recipients = array_unique($recipients);

            // Recipient Type
            $CCBCC = $this->get_cc_bcc_method();

            foreach($recipients as $recipient)
            {
                // Skip if it's not a valid email
                if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

                $headers[] = $CCBCC.': '.$recipient;
            }

            $message = (isset($this->notif_settings['user_event_publishing']['content']) and trim($this->notif_settings['user_event_publishing']['content'])) ? $this->notif_settings['user_event_publishing']['content'] : '';
            $message = $this->get_content($message, 'user_event_publishing', $post->ID);

            // User Data
            $message = str_replace('%%name%%', $guest_name, $message);

            // Site Data
            $message = str_replace('%%blog_name%%', get_bloginfo('name'), $message);
            $message = str_replace('%%blog_url%%', get_bloginfo('url'), $message);
            $message = str_replace('%%blog_description%%', get_bloginfo('description'), $message);

            // Date Format
            $date_format = get_option('date_format');

            // Event Data
            $message = str_replace('%%admin_link%%', $this->link(array('post_type'=>$event_PT), $this->main->URL('admin').'edit.php'), $message);
            $message = str_replace('%%event_title%%', get_the_title($post->ID), $message);
            $message = str_replace('%%event_description%%', strip_tags(strip_shortcodes(get_post_field('post_content', $post->ID))), $message);

            $event_tags = get_the_terms($post->ID, apply_filters('mec_taxonomy_tag', ''));
            $message = str_replace('%%event_tags%%', (is_array($event_tags) ? join(', ', wp_list_pluck($event_tags, 'name')) : ''), $message);

            $event_labels = get_the_terms($post->ID, 'mec_label');
            $message = str_replace('%%event_labels%%', (is_array($event_labels) ? join(', ', wp_list_pluck($event_labels, 'name')) : ''), $message);

            $event_categories = get_the_terms($post->ID, 'mec_category');
            $message = str_replace('%%event_categories%%', (is_array($event_categories) ? join(', ', wp_list_pluck($event_categories, 'name')) : ''), $message);

            $mec_cost = get_post_meta($post->ID, 'mec_cost', true);
            $message = str_replace('%%event_cost%%', (is_numeric($mec_cost) ? $this->main->render_price($mec_cost, $post->ID) : $mec_cost), $message);

            $mec_start_date = get_post_meta($post->ID, 'mec_start_date', true);
            $mec_end_date = get_post_meta($post->ID, 'mec_end_date', true);

            if(!$mec_start_date and !$mec_end_date)
            {
                $mec = isset($_POST['mec']) ? $this->main->sanitize_deep_array($_POST['mec']) : [];

                $mec_start_date = (isset($mec['date']) and isset($mec['date']['start']) and isset($mec['date']['start']['date']) and trim($mec['date']['start']['date'])) ? $this->main->standardize_format(sanitize_text_field($mec['date']['start']['date'])) : NULL;
                $mec_end_date = (isset($mec['date']) and isset($mec['date']['end']) and isset($mec['date']['end']['date']) and trim($mec['date']['end']['date'])) ? $this->main->standardize_format(sanitize_text_field($mec['date']['end']['date'])) : NULL;
            }

            $message = str_replace('%%event_link%%', get_post_permalink($post->ID), $message);
            $message = str_replace('%%event_start_date%%', $this->main->date_i18n($date_format, $mec_start_date), $message);
            $message = str_replace('%%event_end_date%%', $this->main->date_i18n($date_format, $mec_end_date), $message);
            $message = str_replace('%%event_timezone%%', $this->main->get_timezone($post->ID), $message);
            $message = str_replace('%%event_note%%', get_post_meta($post->ID, 'mec_note', true), $message);

            $status_obj = get_post_status_object($status);
            $message = str_replace('%%event_status%%', (($status_obj and isset($status_obj->label)) ? $status_obj->label : $status), $message);

            // Data Fields
            $event_fields = $this->main->get_event_fields();

            $event_fields_data = get_post_meta($post->ID, 'mec_fields', true);
            if(!is_array($event_fields_data)) $event_fields_data = [];

            foreach($event_fields as $f => $event_field)
            {
                if(!is_numeric($f)) continue;

                $field_value = $event_fields_data[$f] ?? '';
                if(!is_array($field_value) and trim($field_value) === '')
                {
                    $message = str_replace('%%event_field_'.$f.'%%', '', $message);
                    $message = str_replace('%%event_field_'.$f.'_with_name%%', '', $message);

                    continue;
                }

                $event_field_name = $event_field['label'] ?? '';
                if(is_array($field_value)) $field_value = implode(', ', $field_value);

                $message = str_replace('%%event_field_'.$f.'%%', trim($field_value, ', '), $message);
                $message = str_replace('%%event_field_'.$f.'_with_name%%', trim((trim($event_field_name) ? $event_field_name.': ' : '').trim($field_value, ', ')), $message);
            }

            $message = str_replace('%%zoom_join%%', get_post_meta($post->ID, 'mec_zoom_join_url', true), $message);
            $message = str_replace('%%zoom_link%%', get_post_meta($post->ID, 'mec_zoom_link_url', true), $message);
            $message = str_replace('%%zoom_password%%', get_post_meta($post->ID, 'mec_zoom_password', true), $message);
            $message = str_replace('%%zoom_embed%%', get_post_meta($post->ID, 'mec_zoom_embed', true), $message);

            $message = apply_filters( 'mec_notifications_user_event_publishing_render_content', $message, $post->ID, $post, $new, $old );

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            // Notification Subject
            $subject = str_replace('%%event_title%%', get_the_title($post->ID), $subject);
            $subject = apply_filters( 'mec_notifications_user_event_publishing_render_subject', $subject, $post->ID, $post, $new, $old );

            // Changing some sender email info.
            $this->mec_sender_email_notification_filter();

            // Set Email Type to HTML
            add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

            // Send the mail
            wp_mail($to, html_entity_decode(stripslashes($subject), ENT_HTML5), wpautop(stripslashes($message)), $headers);

            // Remove the HTML Email filter
            remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));
        }
    }

    public function event_soldout($event_id, $book_id)
    {
        if(!$book_id) return;

        $event_soldout = apply_filters('mec_event_soldout_notification', true);
        if(!$event_soldout) return;

        // Event Soldout Notification is disabled
        if(!isset($this->notif_settings['event_soldout']['status']) or (isset($this->notif_settings['event_soldout']['status']) and !$this->notif_settings['event_soldout']['status'])) return;

        $tos = [];

        // Send the notification to admin
        if(isset($this->notif_settings['event_soldout']['send_to_admin']) and $this->notif_settings['event_soldout']['send_to_admin'] == 1)
        {
            $tos[] = get_bloginfo('admin_email');
        }

        // Send the notification to event organizer
        if(isset($this->notif_settings['event_soldout']['send_to_organizer']) and $this->notif_settings['event_soldout']['send_to_organizer'] == 1)
        {
            $organizer_email = $this->get_booking_organizer_email($book_id);
            if($organizer_email !== false) $tos[] = trim($organizer_email);
        }

        // Send the notification to additional organizers
        if(isset($this->notif_settings['event_soldout']['send_to_additional_organizers']) and $this->notif_settings['event_soldout']['send_to_additional_organizers'] == 1)
        {
            $additional_organizer_emails = $this->get_booking_additional_organizers_emails($book_id);
            if(is_array($additional_organizer_emails) and count($additional_organizer_emails))
            {
                foreach($additional_organizer_emails as $additional_organizer_email) $tos[] = trim($additional_organizer_email);
            }
        }

        // No Recipient
        if(!count($tos)) return;

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['event_soldout']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['event_soldout']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['event_soldout']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        $subject = isset($this->notif_settings['event_soldout']['subject']) ? esc_html__($this->notif_settings['event_soldout']['subject'], 'mec') : esc_html__('Event is soldout!', 'mec');
        $subject = $this->content($this->get_subject($subject, 'event_soldout', $event_id, $book_id), $book_id);

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the mail
        $i = 1;
        foreach($tos as $to)
        {
            $mailto = (is_array($to) and isset($to['email'])) ? $to['email'] : $to;

            if(!trim($mailto) or !filter_var($mailto, FILTER_VALIDATE_EMAIL)) continue;
            if($i > 1) $headers = array('Content-Type: text/html; charset=UTF-8');

            $message = $this->notif_settings['event_soldout']['content'] ?? '';
            $message = $this->content($this->get_content($message, 'event_soldout', $event_id, $book_id), $book_id, (is_array($to) ? $to : NULL));

            // Book Data
            $message = str_replace('%%admin_link%%', $this->link(array('post_type'=>$this->main->get_book_post_type()), $this->main->URL('admin').'edit.php'), $message);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $mailto,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_event_soldout', $mail_arg, $book_id, 'event_soldout');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            $i++;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));
    }

    public function event_finished($event_id, $timestamps)
    {
        if(!$event_id) return false;

        // Event Finished notification is disabled
        if(!isset($this->notif_settings['event_finished']['status']) or (isset($this->notif_settings['event_finished']['status']) and !$this->notif_settings['event_finished']['status'])) return false;

        list($start_timestamp, $end_timestamp) = explode(':', $timestamps);

        // Attendees
        $attendees = $this->main->get_event_attendees($event_id, $start_timestamp);

        // No Attendee
        if(!is_array($attendees) or !count($attendees)) return false;

        $headers = array('Content-Type: text/html; charset=UTF-8');

        $recipients_str = $this->notif_settings['event_finished']['recipients'] ?? '';
        $recipients = trim($recipients_str) ? explode(',', $recipients_str) : [];

        $users = $this->notif_settings['event_finished']['receiver_users'] ?? [];
        $users_down = $this->main->get_emails_by_users($users);
        $recipients = array_merge($users_down, $recipients);

        $roles = $this->notif_settings['event_finished']['receiver_roles'] ?? [];
        $user_roles = $this->main->get_emails_by_roles($roles);
        $recipients = array_merge($user_roles, $recipients);

        // Unique Recipients
        $recipients = array_map('trim', $recipients);
        $recipients = array_unique($recipients);

        // Recipient Type
        $CCBCC = $this->get_cc_bcc_method();

        foreach($recipients as $recipient)
        {
            // Skip if it's not a valid email
            if(trim($recipient) == '' or !filter_var($recipient, FILTER_VALIDATE_EMAIL)) continue;

            $headers[] = $CCBCC.': '.$recipient;
        }

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Do not send email twice!
        $done_emails = [];

        // Send the Emails
        foreach($attendees as $attendee)
        {
            // Book ID
            $book_id = $attendee['book_id'];

            // To Address
            $to = $attendee['email'] ?? '';

            if(!trim($to)) continue;
            if(in_array($to, $done_emails) or !filter_var($to, FILTER_VALIDATE_EMAIL)) continue;

            $subject = isset($this->notif_settings['event_finished']['subject']) ? esc_html__($this->notif_settings['event_finished']['subject'], 'mec') : esc_html__('Thanks for your attention!', 'mec');
            $subject = $this->content($this->get_subject($subject, 'event_finished', $event_id, $book_id), $book_id, $attendee, $timestamps);

            $message = $this->notif_settings['event_finished']['content'] ?? '';

            $message = str_replace('%%zoom_join%%', get_post_meta($event_id, 'mec_zoom_join_url', true), $message);
            $message = str_replace('%%zoom_link%%', get_post_meta($event_id, 'mec_zoom_link_url', true), $message);
            $message = str_replace('%%zoom_password%%', get_post_meta($event_id, 'mec_zoom_password', true), $message);
            $message = str_replace('%%zoom_embed%%', get_post_meta($event_id, 'mec_zoom_embed', true), $message);

            $message = $this->content($this->get_content($message, 'event_finished', $event_id, $book_id), $book_id, $attendee, $timestamps);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);
            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $to,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_booking_reminder', $mail_arg, $book_id, 'booking_reminder');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            $done_emails[] = $to;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        return true;
    }

    public function auto_email($book_id, $subject, $message, $timestamps = NULL)
    {
        if(!$book_id) return false;

        $booker = $this->u->booking($book_id);
        if(!isset($booker->user_email)) return false;

        // Subject
        $subject = $this->content($subject, $book_id);

        $headers = array('Content-Type: text/html; charset=UTF-8');

        // Attendees
        $attendees = get_post_meta($book_id, 'mec_attendees', true);
        if(!is_array($attendees) || !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

        // Do not send email twice!
        $done_emails = [];

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        // Send the emails
        foreach($attendees as $attendee)
        {
            if(isset($attendee[0]['MEC_TYPE_OF_DATA'])) continue;

            $to = $attendee['email'] ?? '';

            if(!trim($to)) continue;
            if(in_array($to, $done_emails) or !filter_var($to, FILTER_VALIDATE_EMAIL)) continue;

            // Message
            $message = $this->content($message, $book_id, $attendee, $timestamps);

            // Remove remained placeholders
            $message = preg_replace('/%%.*%%/', '', $message);

            // Add Template
            $message = $this->add_template($message);

            // Filter the email
            $mail_arg = array(
                'to'            => $to,
                'subject'       => $subject,
                'message'       => $message,
                'headers'       => $headers,
                'attachments'   => array(),
            );

            $mail_arg = apply_filters('mec_before_send_auto_email', $mail_arg, $book_id, 'auto_email');

            // Send the mail
            wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

            $done_emails[] = $to;
        }

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', array($this->main, 'html_email_type'));

        return true;
    }

    /**
     * @param $booking_attendee_id
     * @param $template
     * @return bool
     */
    public function certificate_send($booking_attendee_id, $template)
    {
        if(!$booking_attendee_id) return false;

        $mec_book = $this->main->get_mec_attendee_record($booking_attendee_id);
        if(!isset($mec_book->booking_id)) return false;

        $book_id = $mec_book->booking_id;

        $booker = $this->u->get($mec_book->user_id);
        if(!isset($booker->user_email)) return false;

        // Event ID
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        // Subject
        $subject = isset($this->notif_settings['certificate_send']['subject']) ? esc_html__($this->notif_settings['certificate_send']['subject'], 'mec') : esc_html__('Download your certificate.', 'mec');
        $subject = $this->content($this->get_subject($subject, 'certificate_send', $event_id, $book_id), $book_id);

        $headers = ['Content-Type: text/html; charset=UTF-8'];

        // Changing some sender email info.
        $this->mec_sender_email_notification_filter();

        // Set Email Type to HTML
        add_filter('wp_mail_content_type', [$this->main, 'html_email_type']);

        // Message
        $message = $this->notif_settings['certificate_send']['content'] ?? '';
        $message = $this->content($message, $book_id);

        $certificate_link = $this->main->get_certificate_link($booking_attendee_id, $template);

        // Certificate Link
        $message = str_replace('%%certificate_link%%', $certificate_link, $message);

        // Remove remained placeholders
        $message = preg_replace('/%%.*%%/', '', $message);

        // Add Template
        $message = $this->add_template($message);

        // Filter the email
        $mail_arg = [
            'to'            => $booker->user_email,
            'subject'       => $subject,
            'message'       => $message,
            'headers'       => $headers,
            'attachments'   => [],
        ];

        $mail_arg = apply_filters('mec_before_send_auto_email', $mail_arg, $book_id, 'auto_email');

        // Send the mail
        wp_mail($mail_arg['to'], html_entity_decode(stripslashes($mail_arg['subject']), ENT_HTML5), wpautop(stripslashes($mail_arg['message'])), $mail_arg['headers'], $mail_arg['attachments']);

        // Remove the HTML Email filter
        remove_filter('wp_mail_content_type', [$this->main, 'html_email_type']);

        return true;
    }

    /**
     * Generate a link based on parameters
     * @author Webnus <info@webnus.net>
     * @param array $vars
     * @param string $url
     * @return string
     */
    public function link($vars = array(), $url = NULL)
    {
        if(!trim($url)) $url = $this->main->URL('site').$this->main->get_main_slug().'/';
        foreach($vars as $key=>$value) $url = $this->main->add_qs_var($key, $value, $url);

        return $url;
    }

    /**
     * Generate content of email
     * @param string $message
     * @param int $book_id
     * @param array $attendee
     * @param string $timestamps
     * @return string
     * @author Webnus <info@webnus.net>
     */
    public function content($message, $book_id, $attendee = [], $timestamps = '')
    {
        if(!$book_id) return false;

        // Disable Cache
        $cache = $this->getCache();
        $cache->disable();

        $booker = $this->u->booking($book_id);
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $first_name = isset($booker->first_name) ? $booker->first_name : '';
        $last_name = isset($booker->last_name) ? $booker->last_name : '';
        $name = (isset($booker->first_name) ? trim($booker->first_name.' '.(isset($booker->last_name) ? $booker->last_name : '')) : '');
        $email = (isset($booker->user_email) ? $booker->user_email : '');

        // DB
        $db = $this->getDB();

        /**
         * Get the data from Attendee instead of main booker user
         */
        if(isset($attendee['name']) and trim($attendee['name']))
        {
            $name = $attendee['name'];
            $attendee_ex_name = explode(' ', $name);

            $first_name = $attendee_ex_name[0] ?? '';
            unset($attendee_ex_name[0]);

            $last_name = implode(' ', $attendee_ex_name);
            $email = $attendee['email'] ?? $email;
        }

        // Booker Data
        $message = str_replace('%%first_name%%', $first_name, $message);
        $message = str_replace('%%last_name%%', $last_name, $message);
        $message = str_replace('%%name%%', $name, $message);
        $message = str_replace('%%user_email%%', $email, $message);
        $message = str_replace('%%user_id%%', ($booker->ID ?? ''), $message);

        // Site Data
        $message = str_replace('%%blog_name%%', get_bloginfo('name'), $message);
        $message = str_replace('%%blog_url%%', get_bloginfo('url'), $message);
        $message = str_replace('%%blog_description%%', get_bloginfo('description'), $message);

        // Book Data
        $transaction_id = get_post_meta($book_id, 'mec_transaction_id', true);
        $transaction = $this->book->get_transaction($transaction_id);

        // First for All
        $first_for_all = $transaction['first_for_all'] ?? 0;

        // Date & Time Format
        $date_format = get_option('date_format');
        $time_format = get_option('time_format');

        if(!trim($timestamps)) $timestamps = get_post_meta($book_id, 'mec_date', true);
        list($start_timestamp, $end_timestamp) = explode(':', $timestamps);

        // Occurrence Params
        $params = MEC_feature_occurrences::param($event_id, $start_timestamp, '*');

        // Book Date
        if(trim($timestamps) and strpos($timestamps, ':') !== false)
        {
            if(trim($start_timestamp) != trim($end_timestamp) and date('Y-m-d', $start_timestamp) != date('Y-m-d', $end_timestamp))
            {
                $book_date = sprintf(esc_html__('%s to %s', 'mec'), $this->main->date_i18n($date_format, $start_timestamp), $this->main->date_i18n($date_format, $end_timestamp));
            }
            else $book_date = get_the_date($date_format, $book_id);
        }
        else $book_date = get_the_date($date_format, $book_id);

        $message = str_replace('%%book_date%%', $book_date, $message);

        // Book Time
        $event_start_time = $this->main->get_time($start_timestamp);
        $event_end_time = $this->main->get_time($end_timestamp);

        $allday = get_post_meta($event_id, 'mec_allday', true);
        $hide_time = get_post_meta($event_id, 'mec_hide_time', true);
        $hide_end_time = $this->main->hide_end_time_status($event_id);
        $event_time = $allday ? $this->main->m('all_day', esc_html__('All Day' , 'mec')) : (!$hide_end_time ? sprintf(esc_html__('%s to %s', 'mec'), $event_start_time, $event_end_time) : $event_start_time);

        // Condition for check some parameter simple hide event time
        if(!$hide_time) $message = str_replace('%%book_time%%', $event_time, $message);
        else $message = str_replace('%%book_time%%', '', $message);

        // Book Date & Time
        if(trim($timestamps) and strpos($timestamps, ':') !== false)
        {
            if(trim($start_timestamp) != trim($end_timestamp))
            {
                $book_datetime = sprintf(esc_html__('%s to %s', 'mec'), $this->main->date_i18n($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $start_timestamp), $this->main->date_i18n($date_format.((!$allday and !$hide_time and !$hide_end_time) ? ' '.$time_format : ''), $end_timestamp));
            }
            else $book_datetime = get_the_date($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $book_id);
        }
        else $book_datetime = get_the_date($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $book_id);

        $message = str_replace('%%book_datetime%%', $book_datetime, $message);

        // Other Date & Times
        $other_dates = ((isset($transaction['other_dates']) and is_array($transaction['other_dates'])) ? $transaction['other_dates'] : array());
        $other_dates_datetime = '';

        foreach($other_dates as $other_date)
        {
            list($other_start_timestamp, $other_end_timestamp) = explode(':', $other_date);

            if(trim($other_start_timestamp) != trim($other_end_timestamp)) $other_dates_datetime .= sprintf(esc_html__('%s to %s', 'mec'), $this->main->date_i18n($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $other_start_timestamp), $this->main->date_i18n($date_format.((!$allday and !$hide_time and !$hide_end_time) ? ' '.$time_format : ''), $other_end_timestamp))."<br>";
            else $other_dates_datetime .= $this->main->date_i18n($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $other_start_timestamp)."<br>";
        }

        $message = str_replace('%%book_other_datetimes%%', $other_dates_datetime, $message);

        // Order Time
        $order_time = get_post_meta($book_id, 'mec_booking_time', true);
        $message = str_replace('%%book_order_time%%', $this->main->date_i18n($date_format.' '.$time_format, strtotime($order_time)), $message);

        $message = str_replace('%%invoice_link%%', $this->book->get_invoice_link($transaction_id), $message);

        $cancellation_key = get_post_meta($book_id, 'mec_cancellation_key', true);
        $cancellation_link = trim(get_permalink($event_id), '/').'/cancel/'.$cancellation_key.'/';

        $message = str_replace('%%cancellation_link%%', $cancellation_link, $message);

        // Booking Price
        $price = get_post_meta($book_id, 'mec_price', true);
        $message = str_replace('%%book_price%%', $this->main->render_price(($price ? $price : 0), $event_id), $message);

        // Booking Payable
        $payable = get_post_meta($book_id, 'mec_payable', true);
        $message = str_replace('%%book_payable%%', $this->main->render_price(($payable ? $payable : 0), $event_id), $message);

        // Total Attendees
        $message = str_replace('%%total_attendees%%', $this->book->get_total_attendees($book_id), $message);

        // Attendee Price
        if(isset($attendee['email']))
        {
            $attendee_price = $this->book->get_attendee_price($transaction, $attendee['email']);
            $message = str_replace('%%attendee_price%%', $this->main->render_price(($attendee_price ?: $price), $event_id), $message);
        }

        $event_id = get_post_meta($book_id, 'mec_event_id', true);
        $mec_date = explode(':', get_post_meta($book_id, 'mec_date', true));

        // Booked Tickets
        if(count($mec_date) == 2 and isset($mec_date[0]))
        {
            $booked_tickets = $this->book->get_tickets_availability($event_id, $mec_date[0], 'reservation');
            $message = str_replace('%%amount_tickets%%', $booked_tickets, $message);
        }

        // Attendee Full Information
        if(strpos($message, '%%attendee_full_info%%') !== false || strpos($message, '%%attendees_full_info%%') !== false)
        {
            $attendees_full_info = $this->get_full_attendees_info($book_id);

            $message = str_replace('%%attendee_full_info%%', $attendees_full_info, $message);
            $message = str_replace('%%attendees_full_info%%', $attendees_full_info, $message);
        }

        // Ticket Variations
        if(isset($attendee['variations']) and is_array($attendee['variations']) and count($attendee['variations']))
        {
            $ticket_variations = $this->main->ticket_variations($event_id, $attendee['id']);

            $ticket_variations_str = '';
            foreach($attendee['variations'] as $variation_id => $count)
            {
                if(!isset($ticket_variations[$variation_id])) continue;

                $title = $ticket_variations[$variation_id]['title'] ?? '';
                $ticket_variations_str .= $title.': '.$count."<br>";

                $message = str_replace('%%ticket_variations_'.$variation_id.'_title%%', $title, $message);
                $message = str_replace('%%ticket_variations_'.$variation_id.'_count%%', (int) $count, $message);
            }

            $message = str_replace('%%ticket_variations%%', $ticket_variations_str, $message);
        }

        // Booking IDs
        $message = str_replace('%%booking_id%%', $book_id, $message);
        $message = str_replace('%%booking_transaction_id%%', $transaction_id, $message);

        // Payment Gateway
        $message = str_replace('%%payment_gateway%%', get_post_meta($book_id, 'mec_gateway_label', true), $message);

        // Booking Fixed Fields
        $bfixed_fields = $this->main->get_bfixed_fields($event_id);
        $all_bfixed_fields = '';

        if(is_array($bfixed_fields) and count($bfixed_fields) and isset($transaction['fields']) and is_array($transaction['fields']) and count($transaction['fields']))
        {
            foreach($bfixed_fields as $b => $bfixed_field)
            {
                if(!is_numeric($b)) continue;

                $bfixed_field_name = $bfixed_field['label'] ?? '';
                $bfixed_value = $transaction['fields'][$b] ?? '';

                if(is_array($bfixed_value)) $bfixed_value = implode(', ', $bfixed_value);
                if(trim($bfixed_value) === '') continue;

                $name_and_value = trim((trim($bfixed_field_name) ? stripslashes($bfixed_field_name).': ' : '').trim(stripslashes($bfixed_value), ', '));
                $all_bfixed_fields .= $name_and_value."<br>";

                $message = str_replace('%%booking_field_'.$b.'%%', trim(stripslashes($bfixed_value), ', '), $message);
                $message = str_replace('%%booking_field_'.$b.'_with_name%%', $name_and_value, $message);
            }
        }

        // All Booking Fields
        $message = str_replace('%%all_bfixed_fields%%', $all_bfixed_fields, $message);

        // Event Data
        $organizer_id = $this->main->get_master_organizer_id($event_id, $mec_date[0]);
        $location_id = $this->main->get_master_location_id($event_id, $mec_date[0]);
        $speaker_id = wp_get_post_terms( $event_id, 'mec_speaker', '');

        $organizer = get_term($organizer_id, 'mec_organizer');
        $location = get_term($location_id, 'mec_location');

        // Data Fields
        $event_fields = $this->main->get_event_fields();
        $event_fields_data = get_post_meta($event_id, 'mec_fields', true);
        if(!is_array($event_fields_data)) $event_fields_data = [];

        foreach($event_fields as $f => $event_field)
        {
            if(!is_numeric($f)) continue;

            $event_field_name = $event_field['label'] ?? '';
            $field_value = $event_fields_data[$f] ?? '';
            if((!is_array($field_value) and trim($field_value) === '') or (is_array($field_value) and !count($field_value)))
            {
                $message = str_replace('%%event_field_'.$f.'%%', '', $message);
                $message = str_replace('%%event_field_'.$f.'_with_name%%', '', $message);

                continue;
            }

            if(is_array($field_value)) $field_value = implode(', ', $field_value);

            $message = str_replace('%%event_field_'.$f.'%%', trim(stripslashes($field_value), ', '), $message);
            $message = str_replace('%%event_field_'.$f.'_with_name%%', trim((trim($event_field_name) ? stripslashes($event_field_name).': ' : '').trim(stripslashes($field_value), ', ')), $message);
        }

        $message = str_replace('%%event_title%%', get_the_title($event_id), $message);
        $message = str_replace('%%event_description%%', strip_tags(strip_shortcodes(get_post_field('post_content', $event_id))), $message);

        $event_tags = get_the_terms($event_id, apply_filters('mec_taxonomy_tag', ''));
        $message = str_replace('%%event_tags%%', (is_array($event_tags) ? join(', ', wp_list_pluck($event_tags, 'name')) : ''), $message);

        $event_labels = get_the_terms($event_id, 'mec_label');
        $message = str_replace('%%event_labels%%', (is_array($event_labels) ? join(', ', wp_list_pluck($event_labels, 'name')) : ''), $message);

        $event_categories = get_the_terms($event_id, 'mec_category');
        $message = str_replace('%%event_categories%%', (is_array($event_categories) ? join(', ', wp_list_pluck($event_categories, 'name')) : ''), $message);

        $mec_cost = get_post_meta($event_id, 'mec_cost', true);
        $mec_cost = (isset($params['cost']) and trim($params['cost']) != '') ? preg_replace("/[^0-9.]/", '', $params['cost']) : $mec_cost;

        $read_more = get_post_meta($event_id, 'mec_read_more', true);
        $read_more = (isset($params['read_more']) and trim($params['read_more']) != '') ? $params['read_more'] : $read_more;

        $more_info = get_post_meta($event_id, 'mec_more_info', true);
        $more_info = (isset($params['more_info']) and trim($params['more_info']) != '') ? $params['more_info'] : $more_info;

        $event_link = $this->main->get_event_date_permalink(get_permalink($event_id), date('Y-m-d', $start_timestamp));

        // Add Time
        $repeat_type = get_post_meta($event_id, 'mec_repeat_type', true);
        if($repeat_type === 'custom_days') $event_link = $this->main->add_qs_var('time', $start_timestamp, $event_link);

        $message = str_replace('%%event_cost%%', (is_numeric($mec_cost) ? $this->main->render_price($mec_cost, $event_id) : $mec_cost), $message);
        $message = str_replace('%%event_link%%', $event_link, $message);
        $message = str_replace('%%event_more_info%%', esc_url($read_more), $message);
        $message = str_replace('%%event_other_info%%', esc_url($more_info), $message);
        $message = str_replace('%%event_start_date%%', $this->main->date_i18n($date_format, $start_timestamp), $message);
        $message = str_replace('%%event_end_date%%', $this->main->date_i18n($date_format, $end_timestamp), $message);
        $message = str_replace('%%event_start_time%%', date_i18n($time_format, $start_timestamp), $message);
        $message = str_replace('%%event_end_time%%', date_i18n($time_format, $end_timestamp), $message);
        $message = str_replace('%%event_timezone%%', $this->main->get_timezone($event_id), $message);

        $local_timezone = get_post_meta($book_id, 'mec_local_timezone', true);
        if(is_string($local_timezone) and trim($local_timezone))
        {
            $gmt_offset_seconds = $this->main->get_gmt_offset_seconds(date('Y-m-d', $start_timestamp), $event_id);
            $gmt_start_time = strtotime(date('Y-m-d H:i:s', $start_timestamp)) - $gmt_offset_seconds;
            $gmt_end_time = strtotime(date('Y-m-d H:i:s', $end_timestamp)) - $gmt_offset_seconds;

            $user_timezone = new DateTimeZone($local_timezone);
            $gmt_timezone = new DateTimeZone('GMT');
            $gmt_datetime = new DateTime(date('Y-m-d H:i:s', $gmt_start_time), $gmt_timezone);
            $offset = $user_timezone->getOffset($gmt_datetime);

            $user_start_time = $gmt_start_time + $offset;
            $user_end_time = $gmt_end_time + $offset;

            $message = str_replace('%%event_start_date_local%%', $this->main->date_i18n($date_format, $user_start_time), $message);
            $message = str_replace('%%event_end_date_local%%', $this->main->date_i18n($date_format, $user_end_time), $message);
            $message = str_replace('%%event_start_time_local%%', date_i18n($time_format, $user_start_time), $message);
            $message = str_replace('%%event_end_time_local%%', date_i18n($time_format, $user_end_time), $message);
        }
        else
        {
            $message = str_replace('%%event_start_date_local%%', 'N/A', $message);
            $message = str_replace('%%event_end_date_local%%', 'N/A', $message);
            $message = str_replace('%%event_start_time_local%%', 'N/A', $message);
            $message = str_replace('%%event_end_time_local%%', 'N/A', $message);
        }

        $online_link = MEC_feature_occurrences::param($event_id, $start_timestamp, 'moved_online_link', get_post_meta($event_id, 'mec_moved_online_link', true));
        $message = str_replace('%%online_link%%', esc_url($online_link), $message);

        $featured_image = '';
        $thumbnail_url = $this->main->get_post_thumbnail_url($event_id, 'medium');
        if(trim($thumbnail_url)) $featured_image = '<img src="'.$thumbnail_url.'">';

        $message = str_replace('%%event_featured_image%%', $featured_image, $message);

        $message = str_replace('%%event_organizer_name%%', ($organizer->name ?? ''), $message);
        $message = str_replace('%%event_organizer_tel%%', get_term_meta($organizer_id, 'tel', true), $message);
        $message = str_replace('%%event_organizer_email%%', get_term_meta($organizer_id, 'email', true), $message);
        $message = str_replace('%%event_organizer_url%%', get_term_meta($organizer_id, 'url', true), $message);

        $additional_organizers_name = '';
        $additional_organizers_tel = '';
        $additional_organizers_email = '';
        $additional_organizers_url = '';

        $additional_organizers_ids = get_post_meta($event_id, 'mec_additional_organizer_ids', true);
        if(!is_array($additional_organizers_ids)) $additional_organizers_ids = [];

        foreach($additional_organizers_ids as $additional_organizers_id)
        {
            $additional_organizer = get_term($additional_organizers_id, 'mec_organizer');
            if(isset($additional_organizer->name))
            {
                $additional_organizers_name .= $additional_organizer->name.', ';
                $additional_organizers_tel .= get_term_meta($additional_organizers_id, 'tel', true).'<br>';
                $additional_organizers_email .= get_term_meta($additional_organizers_id, 'email', true).'<br>';
                $additional_organizers_url .= get_term_meta($additional_organizers_id, 'url', true).'<br>';
            }
        }

        $message = str_replace('%%event_other_organizers_name%%', trim($additional_organizers_name, ', '), $message);
        $message = str_replace('%%event_other_organizers_tel%%', trim($additional_organizers_tel, ', '), $message);
        $message = str_replace('%%event_other_organizers_email%%', trim($additional_organizers_email, ', '), $message);
        $message = str_replace('%%event_other_organizers_url%%', trim($additional_organizers_url, ', '), $message);

        $speaker_name = [];
        foreach($speaker_id as $speaker) $speaker_name[] = $speaker->name ?? null;

        $message = str_replace('%%event_speaker_name%%', (isset($speaker_name) ? implode(', ', $speaker_name): ''), $message);
        $message = str_replace('%%event_location_name%%', ($location->name ?? get_term_meta($location_id, 'address', true)), $message);
        $message = str_replace('%%event_location_address%%', get_term_meta($location_id, 'address', true), $message);

        $additional_locations_name = '';
        $additional_locations_address = '';

        $additional_locations_ids = get_post_meta($event_id, 'mec_additional_location_ids', true);
        if(!is_array($additional_locations_ids)) $additional_locations_ids = [];

        foreach($additional_locations_ids as $additional_locations_id)
        {
            $additional_location = get_term($additional_locations_id, 'mec_location');
            if(isset($additional_location->name))
            {
                $additional_locations_name .= $additional_location->name.', ';
                $additional_locations_address .= get_term_meta($additional_locations_id, 'address', true).'<br>';
            }
        }

        $message = str_replace('%%event_other_locations_name%%', trim($additional_locations_name, ', '), $message);
        $message = str_replace('%%event_other_locations_address%%', trim($additional_locations_address, ', '), $message);

        $ticket_names = [];
        $ticket_times = [];
        $ticket_private_descriptions = [];

        $ticket_ids_str = get_post_meta($book_id, 'mec_ticket_id', true);
        $tickets = get_post_meta($event_id, 'mec_tickets', true);

        $ticket_ids = explode(',', $ticket_ids_str);
        $ticket_ids = array_filter($ticket_ids);

        if(!is_array($tickets)) $tickets = [];

        foreach($ticket_ids as $value)
        {
            foreach($tickets as $ticket=>$ticket_info)
            {
                if($ticket != $value) continue;

                $ticket_names[] = $ticket_info['name'];
                $ticket_private_descriptions[] = $ticket_info['private_description'] ?? '';

                $ticket_start_hour = $ticket_info['ticket_start_time_hour'] ?? '';
                $ticket_start_minute = $ticket_info['ticket_start_time_minute'] ?? '';
                $ticket_start_ampm = $ticket_info['ticket_start_time_ampm'] ?? '';
                $ticket_end_hour = $ticket_info['ticket_end_time_hour'] ?? '';
                $ticket_end_minute = $ticket_info['ticket_end_time_minute'] ?? '';
                $ticket_end_ampm = $ticket_info['ticket_end_time_ampm'] ?? '';

                $ticket_start_minute_s = $ticket_start_minute;
                $ticket_end_minute_s = $ticket_end_minute;

                if($ticket_start_minute == '0') $ticket_start_minute_s = '00';
                if($ticket_start_minute == '5') $ticket_start_minute_s = '05';
                if($ticket_end_minute == '0') $ticket_end_minute_s = '00';
                if($ticket_end_minute == '5') $ticket_end_minute_s = '05';

                $ticket_start_seconds = $this->main->time_to_seconds($this->main->to_24hours($ticket_start_hour, $ticket_start_ampm), $ticket_start_minute_s);
                $ticket_end_seconds = $this->main->time_to_seconds($this->main->to_24hours($ticket_end_hour, $ticket_end_ampm), $ticket_end_minute_s);

                $ticket_times[] = $this->main->get_time($ticket_start_seconds).' ' . esc_html__('to' , 'mec') . ' ' . $this->main->get_time($ticket_end_seconds);
            }
        }

        // Private Description
        $private_description_status = (!isset($this->settings['booking_private_description']) || $this->settings['booking_private_description']);

        $ticket_times = array_unique($ticket_times);
        $message = str_replace('%%ticket_time%%', implode(',', $ticket_times), $message);
        $message = str_replace('%%ticket_name%%', implode(',', $ticket_names), $message);

        if($private_description_status) $message = str_replace('%%ticket_private_description%%', implode(',', array_unique($ticket_private_descriptions)), $message);

        $ticket_name_time = '';
        foreach($ticket_names as $t_i=>$ticket_name)
        {
            $ticket_name_time .= $ticket_name.(isset($ticket_times[$t_i]) ? ' ('.$ticket_times[$t_i].'), ' : ', ');
        }

        $message = str_replace('%%ticket_name_time%%', trim($ticket_name_time, ', '), $message);

        $gmt_offset_seconds = $this->main->get_gmt_offset_seconds($start_timestamp, $event_id);
        $event_title = get_the_title($event_id);
        $event_info = get_post($event_id);
        $event_content = trim($event_info->post_content) ? strip_shortcodes(strip_tags($event_info->post_content)) : $event_title;
        $event_content = apply_filters('mec_add_content_to_export_google_calendar_details', $event_content,$event_id );

        $google_calendar_location = get_term_meta($location_id, 'address', true);

        // Recurring Rules
        $rrule = $this->main->get_ical_rrules($event_id, true);

        $google_calendar_link = '<a href="https://calendar.google.com/calendar/render?action=TEMPLATE&text=' . urlencode($event_title) . '&dates='. gmdate('Ymd\\THi00\\Z', ($start_timestamp - $gmt_offset_seconds)) . '/' . gmdate('Ymd\\THi00\\Z', ($end_timestamp - $gmt_offset_seconds)) . '&details=' . urlencode($event_content) . (trim($google_calendar_location) ? '&location=' . urlencode($google_calendar_location) : ''). ((trim($rrule) ? '&recur='.urlencode($rrule) : '')). '" target="_blank">' . esc_html__('+ Add to Google Calendar', 'mec') . '</a>';
        $ical_export_link  = '<a href="' . esc_url($this->main->ical_URL_email($event_id, $book_id, get_the_date('Y-m-d', $book_id))) . '">'. esc_html__('+ iCal / Outlook export', 'mec') . '</a>';

        $message = str_replace('%%google_calendar_link%%', $google_calendar_link, $message);
        $message = str_replace('%%ics_link%%', $ical_export_link, $message);

        // Downloadable File
        $dl_file = $this->book->get_dl_file_link($book_id);
        $message = str_replace('%%dl_file%%', $dl_file, $message);

        $message = str_replace('%%zoom_join%%', get_post_meta($event_id, 'mec_zoom_join_url', true), $message);
        $message = str_replace('%%zoom_link%%', get_post_meta($event_id, 'mec_zoom_link_url', true), $message);
        $message = str_replace('%%zoom_password%%', get_post_meta($event_id, 'mec_zoom_password', true), $message);
        $message = str_replace('%%zoom_embed%%', get_post_meta($event_id, 'mec_zoom_embed', true), $message);

        // Next Occurrences
        $next_occurrences = $db->select("SELECT `tstart`, `tend` FROM `#__mec_dates` WHERE `post_id`='".$event_id."' AND `tstart`>='".$start_timestamp."' ORDER BY `tstart` ASC LIMIT 20", 'loadAssocList');

        $google_calendar_links = '';
        $book_date_next_occurrences = '';
        $book_datetime_next_occurrences = '';

        // Occurrences
        foreach($next_occurrences as $next_occurrence)
        {
            // Book Date
            if(isset($next_occurrence['tstart']) and trim($next_occurrence['tstart']) and isset($next_occurrence['tend']) and trim($next_occurrence['tend']))
            {
                if(trim($next_occurrence['tstart']) != trim($next_occurrence['tend']))
                {
                    $book_date_next_occurrences .= sprintf(esc_html__('%s to %s', 'mec'), $this->main->date_i18n($date_format, $next_occurrence['tstart']), $this->main->date_i18n($date_format, $next_occurrence['tend'])).'<br>';
                    $book_datetime_next_occurrences .= sprintf(esc_html__('%s to %s', 'mec'), $this->main->date_i18n($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $next_occurrence['tstart']), $this->main->date_i18n($date_format.((!$allday and !$hide_time and !$hide_end_time) ? ' '.$time_format : ''), $next_occurrence['tend'])).'<br>';
                }
                else
                {
                    $book_date_next_occurrences .= $this->main->date_i18n($date_format, $next_occurrence['tstart']).'<br>';
                    $book_datetime_next_occurrences .= $this->main->date_i18n($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $next_occurrence['tstart']).'<br>';
                }
            }
            else
            {
                $book_date_next_occurrences .= $this->main->date_i18n($date_format, $next_occurrence['tstart']).'<br>';
                $book_datetime_next_occurrences .= $this->main->date_i18n($date_format.((!$allday and !$hide_time) ? ' '.$time_format : ''), $next_occurrence['tstart']).'<br>';
            }

            $google_calendar_links .= '<a href="https://calendar.google.com/calendar/render?action=TEMPLATE&text=' . urlencode($event_title) . '&dates='. gmdate('Ymd\\THi00\\Z', ($next_occurrence['tstart'] - $gmt_offset_seconds)) . '/' . gmdate('Ymd\\THi00\\Z', ($next_occurrence['tend'] - $gmt_offset_seconds)) . '&details=' . urlencode($event_content) . (trim($google_calendar_location) ? '&location=' . urlencode($google_calendar_location) : ''). '" target="_blank">' . sprintf(esc_html__('+ %s to Google Calendar', 'mec'), date($date_format .' '.$time_format, $next_occurrence['tstart'])) . '</a><br>';
        }

        $message = str_replace('%%google_calendar_link_next_occurrences%%', $google_calendar_links, $message);
        $message = str_replace('%%book_date_next_occurrences%%', $book_date_next_occurrences, $message);
        $message = str_replace('%%book_datetime_next_occurrences%%', $book_datetime_next_occurrences, $message);

        // Enable Cache
        $cache->enable();

        return apply_filters('mec_render_message_email', $message, $book_id, $attendee, $timestamps);
    }

    /**
     * Get Booking Organizer Email by Book ID
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @return string
     */
    public function get_booking_organizer_email($book_id)
    {
        $event_id = get_post_meta($book_id, 'mec_event_id', true);
        $mec_date = explode(':', get_post_meta($book_id, 'mec_date', true));

        $organizer_id = $this->main->get_master_organizer_id($event_id, $mec_date[0]);
        $email = get_term_meta($organizer_id, 'email', true);

        return trim($email) ? $email : false;
    }

    /**
     * Get Emails of Additional Organizers
     * @author Webnus <info@webnus.net>
     * @param int $book_id
     * @return array
     */
    public function get_booking_additional_organizers_emails($book_id)
    {
        $event_id = get_post_meta($book_id, 'mec_event_id', true);

        $organizer_ids = get_post_meta($event_id, 'mec_additional_organizer_ids', true);
        if(!is_array($organizer_ids)) $organizer_ids = [];

        $emails = [];

        $organizer_ids = array_unique($organizer_ids);
        foreach($organizer_ids as $organizer_id)
        {
            $email = get_term_meta($organizer_id, 'email', true);
            if($email and is_email($email)) $emails[] = $email;
        }

        return array_unique($emails);
    }

    /**
     * Get full attendees info
     * @param $book_id
     * @return string
     */
    public function get_full_attendees_info($book_id)
    {
        $attendees_full_info = '';

        $attendees = get_post_meta($book_id, 'mec_attendees', true);
        if(!is_array($attendees) || !count($attendees)) $attendees = array(get_post_meta($book_id, 'mec_attendee', true));

        $event_id = get_post_meta($book_id, 'mec_event_id', true);
        $reg_fields = $this->main->get_reg_fields($event_id);
        $reg_fields = apply_filters( 'mec_notification_reg_fields', $reg_fields, $event_id, $book_id );

        $attachments = (isset($attendees['attachments']) and is_array($attendees['attachments'])) ? $attendees['attachments'] : [];
        $attachment_field = [];
        if(count($attachments))
        {
            foreach($reg_fields as $reg_field_id => $reg_field)
            {
                if(!is_numeric($reg_field_id)) continue;
                if($reg_field['type'] !== 'file') continue;

                $attachment_field = $reg_field;
                break;
            }
        }

        foreach($attendees as $key => $attendee)
        {
            if($key === 'attachments') continue;

            $reg_form = $attendee['reg'] ?? [];

            $attendees_full_info .= esc_html__('Name', 'mec').': '.((isset($attendee['name']) and trim($attendee['name'])) ? $attendee['name'] : '---')."\r\n";
            $attendees_full_info .= esc_html__('Email', 'mec').': '.((isset($attendee['email']) and trim($attendee['email'])) ? $attendee['email'] : '---')."\r\n";

            if(is_array($reg_form) and count($reg_form))
            {
                foreach($reg_form as $field_id=>$value)
                {
                    // Placeholder Keys
                    if(!is_numeric($field_id)) continue;

                    $reg_fields = apply_filters( 'mec_booking_notification_reg_fields', $reg_fields, $field_id);

                    $type = $reg_fields[$field_id]['type'];

                    $label = isset($reg_fields[$field_id]) ? $reg_fields[$field_id]['label'] : '';
                    if(trim($label) == '') continue;

                    if($type == 'agreement')
                    {
                        $label = sprintf(esc_html__($label, 'mec'), '<a href="'.get_the_permalink($reg_fields[$field_id]['page']).'">'.get_the_title($reg_fields[$field_id]['page']).'</a>');
                        $attendees_full_info .= $label.': '.($value == '1' ? esc_html__('Yes', 'mec') : esc_html__('No', 'mec'))."\r\n";
                    }
                    else
                    {
                        $attendees_full_info .= esc_html__($label, 'mec').': '.(is_string($value) ? $value : (is_array($value) ? implode(', ', $value) : '---'))."\r\n";
                    }
                }
            }

            $attendees_full_info .= "\r\n";
        }

        // Attachment
        if(count($attachments))
        {
            $attendees_full_info .= esc_html__($attachment_field['label'], 'mec').': <a href="'.esc_url($attachments[0]['url']).'" target="_blank">'.esc_url($attachments[0]['url']).'</a>'."\r\n";
        }

        return $attendees_full_info;
    }

    /**
     * Add filters for sender name and sender email
     */
    public function mec_sender_email_notification_filter()
    {
        // MEC Notification Sender Email
        add_filter('wp_mail_from_name', [$this, 'notification_sender_name']);
        add_filter('wp_mail_from', [$this, 'notification_sender_email']);
    }

    /**
     * Change Notification Sender Name
     * @param string $sender_name
     * @return string
     */
    public function notification_sender_name($sender_name)
    {
        return (isset($this->settings['booking_sender_name']) and trim($this->settings['booking_sender_name'])) ? stripslashes(trim($this->settings['booking_sender_name'])) : $sender_name;
    }

    /**
     * Change Notification Sender Email
     * @param string $sender_email
     * @return string
     */
    public function notification_sender_email($sender_email)
    {
        return (isset($this->settings['booking_sender_email']) and trim($this->settings['booking_sender_email'])) ? trim($this->settings['booking_sender_email']) : $sender_email;
    }

    /**
     * Add template to the email content
     * @param string $content
     * @return string
     */
    public function add_template($content)
    {
        // MEC Template is disabled
        if(isset($this->settings['notif_template_disable']) and $this->settings['notif_template_disable']) return apply_filters('mec_email_template', $content);

        $style = $this->main->get_styling();
        $bg = $style['notification_bg'] ?? '#f6f6f6';

        return '<table border="0" cellpadding="0" cellspacing="0" class="wn-body" style="background-color: '.esc_attr($bg).'; font-family: -apple-system,BlinkMacSystemFont,Segoe UI,Oxygen,Open Sans, sans-serif;border-collapse: separate; mso-table-lspace: 0; mso-table-rspace: 0; width: 100%;">
            <tr>
                <td class="wn-container" style="display: block; margin: 0 auto !important; max-width: 680px; padding: 10px;font-family: sans-serif; font-size: 14px; vertical-align: top;">
                    <div class="wn-wrapper" style="box-sizing: border-box; padding: 38px 9% 50px; width: 100%; height: auto; background: #fff; background-size: contain; margin-bottom: 25px; margin-top: 30px; border-radius: 4px; box-shadow: 0 3px 55px -18px rgba(0,0,0,0.1);">
                        '.MEC_kses::page($content).'
                    </div>
                </td>
            </tr>
        </table>';
    }

    /**
     * Get notification subject
     * @param $value
     * @param $notification_key
     * @param $event_id
     * @param $book_id
     * @return mixed
     */
    public function get_subject($value, $notification_key, $event_id, $book_id = NULL)
    {
        // Translated Event
        if($book_id)
        {
            $transaction_id = get_post_meta($book_id, 'mec_transaction_id', true);
            $transaction = $this->book->get_transaction($transaction_id);

            // Use Translated Event for Content & Subject
            if(isset($transaction['translated_event_id']) && $transaction['translated_event_id'] && $transaction['translated_event_id'] != $event_id) $event_id = $transaction['translated_event_id'];
        }

        $custom_subject = apply_filters('mec_notification_get_subject', '', $notification_key, $event_id);
        if(!empty($custom_subject)) return $custom_subject;

        $values = get_post_meta($event_id, 'mec_notifications', true);
        if(!is_array($values) or !count($values)) return $value;

        $notification = $values[$notification_key] ?? [];

        if(!is_array($notification) or !count($notification)) return $value;
        if(!isset($notification['status']) or !$notification['status']) return $value;

        return ((isset($notification['subject']) and trim($notification['subject'])) ? $notification['subject'] : $value);
    }

    /**
     * Get Notification Content
     * @param $value
     * @param $notification_key
     * @param $event_id
     * @param $book_id
     * @return mixed
     */
    public function get_content($value, $notification_key, $event_id, $book_id = NULL)
    {
        // Translated Event
        if($book_id)
        {
            $transaction_id = get_post_meta($book_id, 'mec_transaction_id', true);
            $transaction = $this->book->get_transaction($transaction_id);

            // Use Translated Event for Content & Subject
            if(isset($transaction['translated_event_id']) && $transaction['translated_event_id'] && $transaction['translated_event_id'] != $event_id) $event_id = $transaction['translated_event_id'];
        }

        $custom_message = apply_filters('mec_notification_get_content', '', $notification_key, $event_id);
        if(!empty($custom_message)) return $custom_message;

        $values = get_post_meta($event_id, 'mec_notifications', true);
        if(!is_array($values) or !count($values)) return $value;

        $notification = $values[$notification_key] ?? [];

        if(!is_array($notification) or !count($notification)) return $value;
        if(!isset($notification['status']) or !$notification['status']) return $value;

        return ((isset($notification['content']) and trim($notification['content'])) ? $notification['content'] : $value);
    }

    /**
     * @return string
     */
    public function get_cc_bcc_method()
    {
        return ((isset($this->settings['booking_recipients_method']) and trim($this->settings['booking_recipients_method'])) ? strtoupper($this->settings['booking_recipients_method']) : 'BCC');
    }
}