controller.php

<?php
 
namespace Bitrix\Mail\Integration\AI;
 
use Bitrix\Mail\MailMessageTable;
use Bitrix\Main\ArgumentException;
use Bitrix\Main\Event;
use Bitrix\Mail\Helper\Message\MessageThreadLoader;
use Bitrix\Main\ObjectPropertyException;
use Bitrix\Main\SystemException;
 
final class Controller
{
 
    public static function onContextGetMessages(Event $event): array
    {
        $moduleId = $event->getParameter('module');
        $contextId = $event->getParameter('id');
        $contextParameters = $event->getParameter('params');
 
        $isAddedQuote = filter_var(($contextParameters['isAddedQuote'] ?? null), FILTER_VALIDATE_BOOLEAN);
        $messageId = $contextParameters['messageId'];
        $messageIds = $contextParameters['messageIds'];
 
        if (!$moduleId || !$contextId)
        {
            return ['messages' => []];
        }
 
        if (!self::isNeededMailMessageContext($moduleId, $contextId, $isAddedQuote, $messageId, $messageIds))
        {
            return ['messages' => []];
        }
 
        if (!$messageIds)
        {
            $messageThreadLoader = new MessageThreadLoader($messageId);
            $messageThreadLoader->loadFullThreadMessageIds();
            $messageIds = $messageThreadLoader->getThreadMessageIds();
        }
 
        if (!$messageIds)
        {
            return ['messages' => []];
        }
 
        return self::loadMessages($messageIds);
    }
 
    private static function isNeededMailMessageContext(
        string $moduleId,
        string $contextId,
        bool $isAddedQuote,
        ?int $messageId = null,
        ?array $messageIds = null,
    ): bool
    {
        if ($moduleId !== 'mail' || $isAddedQuote !== false)
        {
            return false;
        }
 
        if (!str_starts_with($contextId, 'mail_reply') && !str_starts_with($contextId, 'crm_mail_reply'))
        {
            return false;
        }
 
        if ($messageId < 0 && empty($messageIds))
        {
            return false;
        }
 
        return true;
    }
 
    private static function loadMessages(array $messageIds): array
    {
        $messageIds = array_filter($messageIds, function ($item) {
            return filter_var($item, FILTER_VALIDATE_INT) !== false;
        });
 
        if (empty($messageIds))
        {
            return ['messages' => []];
        }
 
        $message = MailMessageTable::query()
            ->setSelect(['BODY'])
            ->where('ID', end($messageIds))
            ->fetchObject()
        ;
 
        if (!$message)
        {
            return ['messages' => []];
        }
 
        $messages[] = [
            'content' => $message['BODY']]
        ;
 
        return [
            'messages' => $messages,
        ];
    }
}