<?php

namespace BusinessLogic\Attachments;


use BusinessLogic\Exceptions\AccessViolationException;
use BusinessLogic\Exceptions\ApiFriendlyException;
use BusinessLogic\Exceptions\ValidationException;
use BusinessLogic\Security\UserContext;
use BusinessLogic\Security\UserPrivilege;
use BusinessLogic\Security\UserToTicketChecker;
use BusinessLogic\Tickets\Attachment;
use BusinessLogic\Tickets\Ticket;
use BusinessLogic\ValidationModel;
use DataAccess\Attachments\AttachmentGateway;
use DataAccess\Files\FileDeleter;
use DataAccess\Files\FileWriter;
use DataAccess\Tickets\TicketGateway;

class AttachmentHandler {
    /* @var $ticketGateway TicketGateway */
    private $ticketGateway;

    /* @var $attachmentGateway AttachmentGateway */
    private $attachmentGateway;

    /* @var $fileWriter FileWriter */
    private $fileWriter;

    /* @var $fileDeleter FileDeleter */
    private $fileDeleter;

    /* @var  $userToTicketChecker UserToTicketChecker */
    private $userToTicketChecker;

    function __construct(TicketGateway $ticketGateway,
                         AttachmentGateway $attachmentGateway,
                         FileWriter $fileWriter,
                         UserToTicketChecker $userToTicketChecker,
                         FileDeleter $fileDeleter) {
        $this->ticketGateway = $ticketGateway;
        $this->attachmentGateway = $attachmentGateway;
        $this->fileWriter = $fileWriter;
        $this->userToTicketChecker = $userToTicketChecker;
        $this->fileDeleter = $fileDeleter;
    }


    /**
     * @param $createAttachmentModel CreateAttachmentForTicketModel
     * @param $userContext UserContext
     * @param $heskSettings array
     * @return TicketAttachment the newly created attachment
     * @throws \Exception
     */
    function createAttachmentForTicket($createAttachmentModel, $userContext, $heskSettings) {
        $this->validate($createAttachmentModel, $heskSettings);

        $decodedAttachment = base64_decode($createAttachmentModel->attachmentContents);

        $ticket = $this->ticketGateway->getTicketById($createAttachmentModel->ticketId, $heskSettings);

        if ($ticket === null) {
            throw new ApiFriendlyException("Ticket {$createAttachmentModel->ticketId} not found", "Ticket Not Found", 404);
        }

        $extraPermissions = $createAttachmentModel->isEditing
            ? array(UserPrivilege::CAN_EDIT_TICKETS)
            : array();

        if (!$this->userToTicketChecker->isTicketAccessibleToUser($userContext, $ticket, $heskSettings, $extraPermissions)) {
            throw new AccessViolationException("User does not have access to ticket {$ticket->id} being created / edited!");
        }

        $cleanedFileName = $this->cleanFileName($createAttachmentModel->displayName);
        $fileParts = pathinfo($cleanedFileName);

        $ticketAttachment = new TicketAttachment();
        $ticketAttachment->savedName = $this->generateSavedName($ticket->trackingId,
            $cleanedFileName, $fileParts['extension']);
        $ticketAttachment->displayName = $cleanedFileName;
        $ticketAttachment->ticketTrackingId = $ticket->trackingId;
        $ticketAttachment->type = 0;
        $ticketAttachment->downloadCount = 0;

        $ticketAttachment->fileSize =
            $this->fileWriter->writeToFile($ticketAttachment->savedName, $heskSettings['attach_dir'], $decodedAttachment);

        $attachmentId = $this->attachmentGateway->createAttachmentForTicket($ticketAttachment, $heskSettings);

        $this->updateAttachmentsOnTicket($ticket, $ticketAttachment, $attachmentId, $heskSettings);

        $ticketAttachment->id = $attachmentId;

        return $ticketAttachment;
    }

    /**
     * Supports deleting attachments from both ticket messages AND replies
     *
     * @param $ticketId int The ticket ID
     * @param $attachmentId int The attachment ID
     * @param $userContext UserContext
     * @param $heskSettings array
     * @throws ApiFriendlyException
     * @throws \Exception
     */
    function deleteAttachmentFromTicket($ticketId, $attachmentId, $userContext, $heskSettings) {
        $ticket = $this->ticketGateway->getTicketById($ticketId, $heskSettings);

        if ($ticket === null) {
            throw new ApiFriendlyException("Ticket {$ticketId} not found!", "Ticket Not Found", 404);
        }

        if (!$this->userToTicketChecker->isTicketAccessibleToUser($userContext, $ticket, $heskSettings, array(UserPrivilege::CAN_EDIT_TICKETS))) {
            throw new AccessViolationException("User does not have access to ticket {$ticketId} being created / edited!");
        }

        $indexToRemove = -1;
        $attachmentType = AttachmentType::MESSAGE;
        $replyId = -1;
        for ($i = 0; $i < count($ticket->attachments); $i++) {
            $attachment = $ticket->attachments[$i];
            if ($attachment->id === $attachmentId) {
                $indexToRemove = $i;
                $this->fileDeleter->deleteFile($attachment->savedName, $heskSettings['attach_dir']);
                $this->attachmentGateway->deleteAttachment($attachment->id, $heskSettings);
            }
        }

        foreach ($ticket->replies as $reply) {
            for ($i = 0; $i < count($reply->attachments); $i++) {
                $attachment = $reply->attachments[$i];
                if ($attachment->id === $attachmentId) {
                    $indexToRemove = $i;
                    $replyId = $reply->id;
                    $attachmentType = AttachmentType::REPLY;
                    $this->fileDeleter->deleteFile($attachment->savedName, $heskSettings['attach_dir']);
                    $this->attachmentGateway->deleteAttachment($attachment->id, $heskSettings);
                }
            }
        }

        if ($indexToRemove === -1) {
            throw new ApiFriendlyException("Attachment not found for ticket or reply! ID: {$attachmentId}", "Attachment not found", 404);
        }

        if ($attachmentType == AttachmentType::MESSAGE) {
            $attachments = $ticket->attachments;
            unset($attachments[$indexToRemove]);
            $this->ticketGateway->updateAttachmentsForTicket($ticketId, $attachments, $heskSettings);
        } else {
            $attachments = $ticket->replies[$replyId]->attachments;
            unset($attachments[$indexToRemove]);
            $this->ticketGateway->updateAttachmentsForReply($replyId, $attachments, $heskSettings);
        }
    }

    /**
     * @param $createAttachmentModel CreateAttachmentForTicketModel
     * @param $heskSettings array
     * @throws ValidationException
     */
    private function validate($createAttachmentModel, $heskSettings) {
        $errorKeys = array();
        if ($createAttachmentModel->attachmentContents === null ||
            trim($createAttachmentModel->attachmentContents) === '') {
            $errorKeys[] = 'CONTENTS_EMPTY';
        }

        if (base64_decode($createAttachmentModel->attachmentContents, true) === false) {
            $errorKeys[] = 'CONTENTS_NOT_BASE_64';
        }

        if ($createAttachmentModel->displayName === null ||
            trim($createAttachmentModel->displayName === '')) {
            $errorKeys[] = 'DISPLAY_NAME_EMPTY';
        }

        if ($createAttachmentModel->ticketId === null ||
            $createAttachmentModel->ticketId < 1) {
            $errorKeys[] = 'TICKET_ID_MISSING';
        }

        $fileParts = pathinfo($createAttachmentModel->displayName);
        if (!isset($fileParts['extension']) || !in_array(".{$fileParts['extension']}", $heskSettings['attachments']['allowed_types'])) {
            $errorKeys[] = 'EXTENSION_NOT_PERMITTED';
        }

        $fileContents = base64_decode($createAttachmentModel->attachmentContents);
        if (function_exists('mb_strlen')) {
            $fileSize = mb_strlen($fileContents, '8bit');
        } else {
            $fileSize = strlen($fileContents);
        }

        if ($fileSize > $heskSettings['attachments']['max_size']) {
            $errorKeys[] = 'FILE_SIZE_TOO_LARGE';
        }

        if (count($errorKeys) > 0) {
            $validationModel = new ValidationModel();
            $validationModel->errorKeys = $errorKeys;
            throw new ValidationException($validationModel);
        }
    }

    private function generateSavedName($trackingId, $displayName, $fileExtension) {
        $fileExtension = ".{$fileExtension}";
        $useChars = 'AEUYBDGHJLMNPQRSTVWXZ123456789';
        $tmp = uniqid();
        for ($j = 1; $j < 10; $j++) {
            $tmp .= $useChars{mt_rand(0, 29)};
        }


        return substr($trackingId . '_' . md5($tmp . $displayName), 0, 200) . $fileExtension;
    }

    /**
     * @param $displayName string original file name
     * @return string The cleaned file name
     */
    private function cleanFileName($displayName) {
        $filename = str_replace(array('%20', '+'), '-', $displayName);
        $filename = preg_replace('/[\s-]+/', '-', $filename);
        $filename = $this->removeAccents($filename);
        $filename = preg_replace('/[^A-Za-z0-9\.\-_]/', '', $filename);
        $filename = trim($filename, '-_');

        return $filename;
    }

    // The following code has been borrowed from Wordpress, and also from posting_functions.inc.php :P
    // Credits: http://wordpress.org
    private function removeAccents($string)
    {
        if (!preg_match('/[\x80-\xff]/', $string)) {
            return $string;
        }

        if ($this->seemsUtf8($string)) {
            $chars = array(
                // Decompositions for Latin-1 Supplement
                chr(194) . chr(170) => 'a', chr(194) . chr(186) => 'o',
                chr(195) . chr(128) => 'A', chr(195) . chr(129) => 'A',
                chr(195) . chr(130) => 'A', chr(195) . chr(131) => 'A',
                chr(195) . chr(132) => 'A', chr(195) . chr(133) => 'A',
                chr(195) . chr(134) => 'AE', chr(195) . chr(135) => 'C',
                chr(195) . chr(136) => 'E', chr(195) . chr(137) => 'E',
                chr(195) . chr(138) => 'E', chr(195) . chr(139) => 'E',
                chr(195) . chr(140) => 'I', chr(195) . chr(141) => 'I',
                chr(195) . chr(142) => 'I', chr(195) . chr(143) => 'I',
                chr(195) . chr(144) => 'D', chr(195) . chr(145) => 'N',
                chr(195) . chr(146) => 'O', chr(195) . chr(147) => 'O',
                chr(195) . chr(148) => 'O', chr(195) . chr(149) => 'O',
                chr(195) . chr(150) => 'O', chr(195) . chr(153) => 'U',
                chr(195) . chr(154) => 'U', chr(195) . chr(155) => 'U',
                chr(195) . chr(156) => 'U', chr(195) . chr(157) => 'Y',
                chr(195) . chr(158) => 'TH', chr(195) . chr(159) => 's',
                chr(195) . chr(160) => 'a', chr(195) . chr(161) => 'a',
                chr(195) . chr(162) => 'a', chr(195) . chr(163) => 'a',
                chr(195) . chr(164) => 'a', chr(195) . chr(165) => 'a',
                chr(195) . chr(166) => 'ae', chr(195) . chr(167) => 'c',
                chr(195) . chr(168) => 'e', chr(195) . chr(169) => 'e',
                chr(195) . chr(170) => 'e', chr(195) . chr(171) => 'e',
                chr(195) . chr(172) => 'i', chr(195) . chr(173) => 'i',
                chr(195) . chr(174) => 'i', chr(195) . chr(175) => 'i',
                chr(195) . chr(176) => 'd', chr(195) . chr(177) => 'n',
                chr(195) . chr(178) => 'o', chr(195) . chr(179) => 'o',
                chr(195) . chr(180) => 'o', chr(195) . chr(181) => 'o',
                chr(195) . chr(182) => 'o', chr(195) . chr(184) => 'o',
                chr(195) . chr(185) => 'u', chr(195) . chr(186) => 'u',
                chr(195) . chr(187) => 'u', chr(195) . chr(188) => 'u',
                chr(195) . chr(189) => 'y', chr(195) . chr(190) => 'th',
                chr(195) . chr(191) => 'y', chr(195) . chr(152) => 'O',
                // Decompositions for Latin Extended-A
                chr(196) . chr(128) => 'A', chr(196) . chr(129) => 'a',
                chr(196) . chr(130) => 'A', chr(196) . chr(131) => 'a',
                chr(196) . chr(132) => 'A', chr(196) . chr(133) => 'a',
                chr(196) . chr(134) => 'C', chr(196) . chr(135) => 'c',
                chr(196) . chr(136) => 'C', chr(196) . chr(137) => 'c',
                chr(196) . chr(138) => 'C', chr(196) . chr(139) => 'c',
                chr(196) . chr(140) => 'C', chr(196) . chr(141) => 'c',
                chr(196) . chr(142) => 'D', chr(196) . chr(143) => 'd',
                chr(196) . chr(144) => 'D', chr(196) . chr(145) => 'd',
                chr(196) . chr(146) => 'E', chr(196) . chr(147) => 'e',
                chr(196) . chr(148) => 'E', chr(196) . chr(149) => 'e',
                chr(196) . chr(150) => 'E', chr(196) . chr(151) => 'e',
                chr(196) . chr(152) => 'E', chr(196) . chr(153) => 'e',
                chr(196) . chr(154) => 'E', chr(196) . chr(155) => 'e',
                chr(196) . chr(156) => 'G', chr(196) . chr(157) => 'g',
                chr(196) . chr(158) => 'G', chr(196) . chr(159) => 'g',
                chr(196) . chr(160) => 'G', chr(196) . chr(161) => 'g',
                chr(196) . chr(162) => 'G', chr(196) . chr(163) => 'g',
                chr(196) . chr(164) => 'H', chr(196) . chr(165) => 'h',
                chr(196) . chr(166) => 'H', chr(196) . chr(167) => 'h',
                chr(196) . chr(168) => 'I', chr(196) . chr(169) => 'i',
                chr(196) . chr(170) => 'I', chr(196) . chr(171) => 'i',
                chr(196) . chr(172) => 'I', chr(196) . chr(173) => 'i',
                chr(196) . chr(174) => 'I', chr(196) . chr(175) => 'i',
                chr(196) . chr(176) => 'I', chr(196) . chr(177) => 'i',
                chr(196) . chr(178) => 'IJ', chr(196) . chr(179) => 'ij',
                chr(196) . chr(180) => 'J', chr(196) . chr(181) => 'j',
                chr(196) . chr(182) => 'K', chr(196) . chr(183) => 'k',
                chr(196) . chr(184) => 'k', chr(196) . chr(185) => 'L',
                chr(196) . chr(186) => 'l', chr(196) . chr(187) => 'L',
                chr(196) . chr(188) => 'l', chr(196) . chr(189) => 'L',
                chr(196) . chr(190) => 'l', chr(196) . chr(191) => 'L',
                chr(197) . chr(128) => 'l', chr(197) . chr(129) => 'L',
                chr(197) . chr(130) => 'l', chr(197) . chr(131) => 'N',
                chr(197) . chr(132) => 'n', chr(197) . chr(133) => 'N',
                chr(197) . chr(134) => 'n', chr(197) . chr(135) => 'N',
                chr(197) . chr(136) => 'n', chr(197) . chr(137) => 'N',
                chr(197) . chr(138) => 'n', chr(197) . chr(139) => 'N',
                chr(197) . chr(140) => 'O', chr(197) . chr(141) => 'o',
                chr(197) . chr(142) => 'O', chr(197) . chr(143) => 'o',
                chr(197) . chr(144) => 'O', chr(197) . chr(145) => 'o',
                chr(197) . chr(146) => 'OE', chr(197) . chr(147) => 'oe',
                chr(197) . chr(148) => 'R', chr(197) . chr(149) => 'r',
                chr(197) . chr(150) => 'R', chr(197) . chr(151) => 'r',
                chr(197) . chr(152) => 'R', chr(197) . chr(153) => 'r',
                chr(197) . chr(154) => 'S', chr(197) . chr(155) => 's',
                chr(197) . chr(156) => 'S', chr(197) . chr(157) => 's',
                chr(197) . chr(158) => 'S', chr(197) . chr(159) => 's',
                chr(197) . chr(160) => 'S', chr(197) . chr(161) => 's',
                chr(197) . chr(162) => 'T', chr(197) . chr(163) => 't',
                chr(197) . chr(164) => 'T', chr(197) . chr(165) => 't',
                chr(197) . chr(166) => 'T', chr(197) . chr(167) => 't',
                chr(197) . chr(168) => 'U', chr(197) . chr(169) => 'u',
                chr(197) . chr(170) => 'U', chr(197) . chr(171) => 'u',
                chr(197) . chr(172) => 'U', chr(197) . chr(173) => 'u',
                chr(197) . chr(174) => 'U', chr(197) . chr(175) => 'u',
                chr(197) . chr(176) => 'U', chr(197) . chr(177) => 'u',
                chr(197) . chr(178) => 'U', chr(197) . chr(179) => 'u',
                chr(197) . chr(180) => 'W', chr(197) . chr(181) => 'w',
                chr(197) . chr(182) => 'Y', chr(197) . chr(183) => 'y',
                chr(197) . chr(184) => 'Y', chr(197) . chr(185) => 'Z',
                chr(197) . chr(186) => 'z', chr(197) . chr(187) => 'Z',
                chr(197) . chr(188) => 'z', chr(197) . chr(189) => 'Z',
                chr(197) . chr(190) => 'z', chr(197) . chr(191) => 's',
                // Decompositions for Latin Extended-B
                chr(200) . chr(152) => 'S', chr(200) . chr(153) => 's',
                chr(200) . chr(154) => 'T', chr(200) . chr(155) => 't',
                // Euro Sign
                chr(226) . chr(130) . chr(172) => 'E',
                // GBP (Pound) Sign
                chr(194) . chr(163) => '',
                // Vowels with diacritic (Vietnamese)
                // unmarked
                chr(198) . chr(160) => 'O', chr(198) . chr(161) => 'o',
                chr(198) . chr(175) => 'U', chr(198) . chr(176) => 'u',
                // grave accent
                chr(225) . chr(186) . chr(166) => 'A', chr(225) . chr(186) . chr(167) => 'a',
                chr(225) . chr(186) . chr(176) => 'A', chr(225) . chr(186) . chr(177) => 'a',
                chr(225) . chr(187) . chr(128) => 'E', chr(225) . chr(187) . chr(129) => 'e',
                chr(225) . chr(187) . chr(146) => 'O', chr(225) . chr(187) . chr(147) => 'o',
                chr(225) . chr(187) . chr(156) => 'O', chr(225) . chr(187) . chr(157) => 'o',
                chr(225) . chr(187) . chr(170) => 'U', chr(225) . chr(187) . chr(171) => 'u',
                chr(225) . chr(187) . chr(178) => 'Y', chr(225) . chr(187) . chr(179) => 'y',
                // hook
                chr(225) . chr(186) . chr(162) => 'A', chr(225) . chr(186) . chr(163) => 'a',
                chr(225) . chr(186) . chr(168) => 'A', chr(225) . chr(186) . chr(169) => 'a',
                chr(225) . chr(186) . chr(178) => 'A', chr(225) . chr(186) . chr(179) => 'a',
                chr(225) . chr(186) . chr(186) => 'E', chr(225) . chr(186) . chr(187) => 'e',
                chr(225) . chr(187) . chr(130) => 'E', chr(225) . chr(187) . chr(131) => 'e',
                chr(225) . chr(187) . chr(136) => 'I', chr(225) . chr(187) . chr(137) => 'i',
                chr(225) . chr(187) . chr(142) => 'O', chr(225) . chr(187) . chr(143) => 'o',
                chr(225) . chr(187) . chr(148) => 'O', chr(225) . chr(187) . chr(149) => 'o',
                chr(225) . chr(187) . chr(158) => 'O', chr(225) . chr(187) . chr(159) => 'o',
                chr(225) . chr(187) . chr(166) => 'U', chr(225) . chr(187) . chr(167) => 'u',
                chr(225) . chr(187) . chr(172) => 'U', chr(225) . chr(187) . chr(173) => 'u',
                chr(225) . chr(187) . chr(182) => 'Y', chr(225) . chr(187) . chr(183) => 'y',
                // tilde
                chr(225) . chr(186) . chr(170) => 'A', chr(225) . chr(186) . chr(171) => 'a',
                chr(225) . chr(186) . chr(180) => 'A', chr(225) . chr(186) . chr(181) => 'a',
                chr(225) . chr(186) . chr(188) => 'E', chr(225) . chr(186) . chr(189) => 'e',
                chr(225) . chr(187) . chr(132) => 'E', chr(225) . chr(187) . chr(133) => 'e',
                chr(225) . chr(187) . chr(150) => 'O', chr(225) . chr(187) . chr(151) => 'o',
                chr(225) . chr(187) . chr(160) => 'O', chr(225) . chr(187) . chr(161) => 'o',
                chr(225) . chr(187) . chr(174) => 'U', chr(225) . chr(187) . chr(175) => 'u',
                chr(225) . chr(187) . chr(184) => 'Y', chr(225) . chr(187) . chr(185) => 'y',
                // acute accent
                chr(225) . chr(186) . chr(164) => 'A', chr(225) . chr(186) . chr(165) => 'a',
                chr(225) . chr(186) . chr(174) => 'A', chr(225) . chr(186) . chr(175) => 'a',
                chr(225) . chr(186) . chr(190) => 'E', chr(225) . chr(186) . chr(191) => 'e',
                chr(225) . chr(187) . chr(144) => 'O', chr(225) . chr(187) . chr(145) => 'o',
                chr(225) . chr(187) . chr(154) => 'O', chr(225) . chr(187) . chr(155) => 'o',
                chr(225) . chr(187) . chr(168) => 'U', chr(225) . chr(187) . chr(169) => 'u',
                // dot below
                chr(225) . chr(186) . chr(160) => 'A', chr(225) . chr(186) . chr(161) => 'a',
                chr(225) . chr(186) . chr(172) => 'A', chr(225) . chr(186) . chr(173) => 'a',
                chr(225) . chr(186) . chr(182) => 'A', chr(225) . chr(186) . chr(183) => 'a',
                chr(225) . chr(186) . chr(184) => 'E', chr(225) . chr(186) . chr(185) => 'e',
                chr(225) . chr(187) . chr(134) => 'E', chr(225) . chr(187) . chr(135) => 'e',
                chr(225) . chr(187) . chr(138) => 'I', chr(225) . chr(187) . chr(139) => 'i',
                chr(225) . chr(187) . chr(140) => 'O', chr(225) . chr(187) . chr(141) => 'o',
                chr(225) . chr(187) . chr(152) => 'O', chr(225) . chr(187) . chr(153) => 'o',
                chr(225) . chr(187) . chr(162) => 'O', chr(225) . chr(187) . chr(163) => 'o',
                chr(225) . chr(187) . chr(164) => 'U', chr(225) . chr(187) . chr(165) => 'u',
                chr(225) . chr(187) . chr(176) => 'U', chr(225) . chr(187) . chr(177) => 'u',
                chr(225) . chr(187) . chr(180) => 'Y', chr(225) . chr(187) . chr(181) => 'y',
                // Vowels with diacritic (Chinese, Hanyu Pinyin)
                chr(201) . chr(145) => 'a',
                // macron
                chr(199) . chr(149) => 'U', chr(199) . chr(150) => 'u',
                // acute accent
                chr(199) . chr(151) => 'U', chr(199) . chr(152) => 'u',
                // caron
                chr(199) . chr(141) => 'A', chr(199) . chr(142) => 'a',
                chr(199) . chr(143) => 'I', chr(199) . chr(144) => 'i',
                chr(199) . chr(145) => 'O', chr(199) . chr(146) => 'o',
                chr(199) . chr(147) => 'U', chr(199) . chr(148) => 'u',
                chr(199) . chr(153) => 'U', chr(199) . chr(154) => 'u',
                // grave accent
                chr(199) . chr(155) => 'U', chr(199) . chr(156) => 'u',
            );

            $string = strtr($string, $chars);
        } else {
            // Assume ISO-8859-1 if not UTF-8
            $chars['in'] = chr(128) . chr(131) . chr(138) . chr(142) . chr(154) . chr(158)
                . chr(159) . chr(162) . chr(165) . chr(181) . chr(192) . chr(193) . chr(194)
                . chr(195) . chr(196) . chr(197) . chr(199) . chr(200) . chr(201) . chr(202)
                . chr(203) . chr(204) . chr(205) . chr(206) . chr(207) . chr(209) . chr(210)
                . chr(211) . chr(212) . chr(213) . chr(214) . chr(216) . chr(217) . chr(218)
                . chr(219) . chr(220) . chr(221) . chr(224) . chr(225) . chr(226) . chr(227)
                . chr(228) . chr(229) . chr(231) . chr(232) . chr(233) . chr(234) . chr(235)
                . chr(236) . chr(237) . chr(238) . chr(239) . chr(241) . chr(242) . chr(243)
                . chr(244) . chr(245) . chr(246) . chr(248) . chr(249) . chr(250) . chr(251)
                . chr(252) . chr(253) . chr(255);

            $chars['out'] = "EfSZszYcYuAAAAAACEEEEIIIINOOOOOOUUUUYaaaaaaceeeeiiiinoooooouuuuyy";

            $string = strtr($string, $chars['in'], $chars['out']);
            $double_chars['in'] = array(chr(140), chr(156), chr(198), chr(208), chr(222), chr(223), chr(230), chr(240), chr(254));
            $double_chars['out'] = array('OE', 'oe', 'AE', 'DH', 'TH', 'ss', 'ae', 'dh', 'th');
            $string = str_replace($double_chars['in'], $double_chars['out'], $string);
        }

        return $string;
    }

    private function seemsUtf8($str)
    {
        $length = strlen($str);
        for ($i = 0; $i < $length; $i++) {
            $c = ord($str[$i]);
            if ($c < 0x80) $n = 0; # 0bbbbbbb
            elseif (($c & 0xE0) == 0xC0) $n = 1; # 110bbbbb
            elseif (($c & 0xF0) == 0xE0) $n = 2; # 1110bbbb
            elseif (($c & 0xF8) == 0xF0) $n = 3; # 11110bbb
            elseif (($c & 0xFC) == 0xF8) $n = 4; # 111110bb
            elseif (($c & 0xFE) == 0xFC) $n = 5; # 1111110b
            else return false; # Does not match any model
            for ($j = 0; $j < $n; $j++) { # n bytes matching 10bbbbbb follow ?
                if ((++$i == $length) || ((ord($str[$i]) & 0xC0) != 0x80))
                    return false;
            }
        }
        return true;
    }

    /**
     * @param $ticket Ticket
     * @param $ticketAttachment TicketAttachment
     * @param $attachmentId int
     * @param $heskSettings array
     */
    private function updateAttachmentsOnTicket($ticket, $ticketAttachment, $attachmentId, $heskSettings) {
        $attachments = $ticket->attachments === null ? array() : $ticket->attachments;
        $newAttachment = new Attachment();
        $newAttachment->savedName = $ticketAttachment->savedName;
        $newAttachment->fileName = $ticketAttachment->displayName;
        $newAttachment->id = $attachmentId;
        $attachments[] = $newAttachment;
        $this->ticketGateway->updateAttachmentsForTicket($ticket->id, $attachments, $heskSettings);
    }
}