Initial service DAV module

lib/Backends/PrincipalBackend.php

@@ -0,0 +1,97 @@
+<?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,
+        ];
+    }
+}