invoiceninja/app/Services/Quote/SendEmail.php

<?php

namespace App\Services\Quote;

use App\Helpers\Email\QuoteEmail;
use App\Jobs\Quote\EmailQuote;
use App\Models\ClientContact;
use App\Models\Quote;

class SendEmail
{
    public $quote;

    protected $reminder_template;

    protected $contact;

    public function __construct($quote, $reminder_template = null, ClientContact $contact = null)
    {
        $this->quote = $quote;

        $this->reminder_template = $reminder_template;

        $this->contact = $contact;
    }

    /**
     * Builds the correct template to send
     * @param string $this->reminder_template The template name ie reminder1
     * @return array
     */
    public function run(): array
    {
        if (!$this->reminder_template) {
            $this->reminder_template = $this->quote->calculateTemplate();
        }

        $this->quote->invitations->each(function ($invitation) {
            if ($invitation->contact->send_email && $invitation->contact->email) {
                $email_builder = (new QuoteEmail())->build($invitation, $this->reminder_template);

                EmailQuote::dispatchNow($email_builder, $invitation);
            }
        });
    }
}