Attachment count is not valid (0) with emails with a RELATED part that has more parts inside

[williamdes]

See: http://sgerwk.altervista.org/imapbodystructure.html

Subject: [Dmarc] =?utf-8?q?Report_Domain=3A_phpmyadmin=2Enet_Submitter=3A?=
    =?utf-8?q?_seznam=2Ecz_Report-ID=3A_szn=5Fphpmyadmin=2Enet-2022-03?=
    =?utf-8?q?-12?=

Content-Type: multipart/mixed; boundary="===============6354937196052198187=="

--===============6354937196052198187==
Content-Type: multipart/related;
    boundary="=_1baa9e3e522aec2136f10cef=177b6dc0-0a05-5f85-8902-5f8c7f19927a_="

--=_1baa9e3e522aec2136f10cef=177b6dc0-0a05-5f85-8902-5f8c7f19927a_=
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

This is a DMARC aggregate report for phpmyadmin.net generated at Sun Mar 13 
12:05:29 2022
--=_1baa9e3e522aec2136f10cef=177b6dc0-0a05-5f85-8902-5f8c7f19927a_=
Content-Type: application/zip;
    name="seznam.cz!phpmyadmin.net!1647043200!1647129600.xml.zip"
Content-Id: <cid_787>
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
    size=1615;
    filename="seznam.cz!phpmyadmin.net!1647043200!1647129600.xml.zip"

UEsDBB[...]AAEAYAAAANkFAAAAAA==
--=_1baa9e3e522aec2136f10cef=177b6dc0-0a05-5f85-8902-5f8c7f19927a_=--

--===============6354937196052198187==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
dmarc mailing list

--===============6354937196052198187==--

The code to handle parts in parts is present on this PHP example: https://www.php.net/manual/fr/function.imap-fetchbody.php#89002

I am working on a fix

I made a cleaned up version of the example, but did not run it:

    function create_part_array($structure, $prefix = '')
    {
        // There some sub parts
        if (count($structure->parts) > 0) {
            foreach ($structure->parts as $count => $part) {
                add_part_to_array($part, $prefix . ($count + 1), $part_array);
            }
            return $part_array;
        }

        // Email does not have a separate mime attachment for text
        $part_array[] = ['part_number' => $prefix . '1', 'part_object' => $obj];
        return $part_array;
    }

    function add_part_to_array($obj, $partNo, &$part_array)
    {
        $part_array[] = ['part_number' => $partNo, 'part_object' => $obj];
         // Check to see if the part is an attached email message, as in the RFC-822 type
        if ($obj->type === 2) {
            // Check to see if the email has parts
            if (count($obj->parts) > 0) {
                foreach ($obj->parts as $index => $part) {
                    // Iterate here again to compensate for the broken way that imap_fetchbody() handles attachments
                    if (count($part->parts) > 0) {
                        foreach ($part->parts as $subIndex => $subPart) {
                            add_part_to_array($subPart, $partNo . '.' . ($subIndex + 1), $part_array);
                        }
                    } else {    // Attached email does not have a separate mime attachment for text
                        $part_array[] = ['part_number' => $partNo . '.' . ($index + 1), 'part_object' => $obj];
                    }
                }
                return;
            }
            // Not sure if this is possible
            $part_array[] = ['part_number' => $prefix . '.1', 'part_object' => $obj];
            return;
        }

        // If there are more sub-parts, expand them out.
        if (count($obj->parts) > 0) {
            foreach ($obj->parts as $count => $p) {
                add_part_to_array($p, $partNo . '.' . ($count + 1), $part_array);
            }
        }
    }

I finally did not use this code, only the basic logic