<?php

declare(strict_types=1);

namespace KTXM\ServiceDav\Backends;

use KTXC\SessionIdentity;
use KTXC\SessionTenant;
use KTXM\ServiceDav\DavProperties;
use Sabre\DAVACL\PrincipalBackend\BackendInterface;

/**
 * DAVACL principal backend.
 */
class PrincipalBackend implements BackendInterface
{
    public const PRINCIPAL_PREFIX = 'principals';

    public function __construct(
        private readonly SessionIdentity $identity,
        private readonly SessionTenant $tenant,
    ) {}

    // -------------------------------------------------------------------------
    // BackendInterface
    // -------------------------------------------------------------------------

    public function getPrincipalsByPrefix($prefixPath): array
    {
        if ($prefixPath !== self::PRINCIPAL_PREFIX || $this->identity->identity() === null) {
            return [];
        }

        return [$this->buildPrincipal()];
    }

    public function getPrincipalByPath($path): ?array
    {
        if ($this->identity->identity() === null) {
            return null;
        }

        $expected = self::PRINCIPAL_PREFIX . '/' . $this->identity->identifier();
        if ($path !== $expected) {
            return null;
        }

        return $this->buildPrincipal();
    }

    public function getGroupMemberSet($principal): array
    {
        return [];
    }

    public function getGroupMembership($principal): array
    {
        return [];
    }

    public function setGroupMemberSet($principal, $members): void
    {
        // not supported
    }

    public function updatePrincipal($path, $propPatch): int
    {
        return 403;
    }

    public function searchPrincipals($prefixPath, $searchProperties, $test = 'allof'): array
    {
        return [];
    }

    public function findByUri($uri, $principalPrefix): ?string
    {
        return null;
    }

    // -------------------------------------------------------------------------
    // Helpers
    // -------------------------------------------------------------------------

    private function buildPrincipal(): array
    {
        $userId = $this->identity->identifier();
        $label  = $this->identity->label() ?? $userId;
        $email  = $this->identity->mailAddress() ?? '';

        return [
            DavProperties::URI          => self::PRINCIPAL_PREFIX . '/' . $userId,
            DavProperties::DISPLAYNAME  => $label,
            DavProperties::SABRE_EMAIL  => $email,
        ];
    }
}