opnform/app/Notifications/Forms/FormSubmissionNotification.php

<?php

namespace App\Notifications\Forms;

use App\Events\Forms\FormSubmitted;
use App\Service\Forms\FormSubmissionFormatter;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Notifications\Messages\MailMessage;
use Illuminate\Notifications\Notification;
use Illuminate\Support\Str;
use Illuminate\Support\Arr;

class FormSubmissionNotification extends Notification implements ShouldQueue
{
    use Queueable;

    public FormSubmitted $event;

    /**
     * Create a new notification instance.
     *
     * @return void
     */
    public function __construct(FormSubmitted $event)
    {
        $this->event = $event;
    }

    /**
     * Get the notification's delivery channels.
     *
     * @param  mixed  $notifiable
     * @return array
     */
    public function via($notifiable)
    {
        return ['mail'];
    }

    /**
     * Get the mail representation of the notification.
     *
     * @param  mixed  $notifiable
     * @return \Illuminate\Notifications\Messages\MailMessage
     */
    public function toMail($notifiable)
    {
        $formatter = (new FormSubmissionFormatter($this->event->form, $this->event->data))
            ->showHiddenFields()
            ->createLinks()
            ->outputStringsOnly()
            ->useSignedUrlForFiles();

        return (new MailMessage)
            ->replyTo($this->getReplyToEmail($notifiable->routes['mail']))
            ->from($this->getFromEmail(), config('app.name'))
            ->subject('New form submission for "'.$this->event->form->title.'"')
            ->markdown('mail.form.submission-notification', [
                'fields' => $formatter->getFieldsWithValue(),
                'form' => $this->event->form,
            ]);
    }

    private function getFromEmail()
    {
        $originalFromAddress = Str::of(config('mail.from.address'))->explode('@');
        return $originalFromAddress->first(). '+' . time() . '@' . $originalFromAddress->last();
    }

    private function getReplyToEmail($default)
    {
        $replyTo = Arr::get((array)$this->event->form->notification_settings, 'notification_reply_to', null);
        if ($replyTo && $this->validateEmail($replyTo)) {
            return $replyTo;
        }
        return $this->getRespondentEmail() ?? $default;
    }

    private function getRespondentEmail()
    {
        // Make sure we only have one email field in the form
        $emailFields = collect($this->event->form->properties)->filter(function ($field) {
            $hidden = $field['hidden'] ?? false;

            return !$hidden && $field['type'] == 'email';
        });
        if ($emailFields->count() != 1) {
            return null;
        }

        if (isset($this->event->data[$emailFields->first()['id']])) {
            $email = $this->event->data[$emailFields->first()['id']];
            if ($this->validateEmail($email)) {
                return $email;
            }
        }

        return null;
    }

    public static function validateEmail($email): bool
    {
        return (bool)filter_var($email, FILTER_VALIDATE_EMAIL);
    }

}