fix(isLegitimatedForUserId): Setup mountpoints to check file access

This fixes workflows on groupfolders, as it will consider access to
files in groupfolders.

It also fixes false positives where access to files was limited by other
means not taken into account before, e.g. access control.

Fixes: nextcloud/flow_notifications#71

Signed-off-by: Jonas <jonas@freesources.org>

apps/workflowengine/lib/Entity/File.php

@@ -26,6 +26,7 @@
  */
 namespace OCA\WorkflowEngine\Entity;
 
+use OC\Files\Config\UserMountCache;
 use OCP\EventDispatcher\Event;
 use OCP\EventDispatcher\GenericEvent;
 use OCP\Files\InvalidPathException;
@@ -77,6 +78,8 @@ class File implements IEntity, IDisplayText, IUrl, IIcon, IContextPortation {
 	private $actingUser = null;
 	/** @var IUserManager */
 	private $userManager;
+	/** @var UserMountCache */
+	private $userMountCache;
 
 	public function __construct(
 		IL10N $l10n,
@@ -86,7 +89,8 @@ public function __construct(
 		ShareManager $shareManager,
 		IUserSession $userSession,
 		ISystemTagManager $tagManager,
-		IUserManager $userManager
+		IUserManager $userManager,
+		UserMountCache $userMountCache
 	) {
 		$this->l10n = $l10n;
 		$this->urlGenerator = $urlGenerator;
@@ -96,6 +100,7 @@ public function __construct(
 		$this->userSession = $userSession;
 		$this->tagManager = $tagManager;
 		$this->userManager = $userManager;
+		$this->userMountCache = $userMountCache;
 	}
 
 	public function getName(): string {
@@ -136,12 +141,19 @@ public function prepareRuleMatcher(IRuleMatcher $ruleMatcher, string $eventName,
 
 	public function isLegitimatedForUserId(string $uid): bool {
 		try {
-			$node = $this->getNode();
-			if ($node->getOwner()->getUID() === $uid) {
-				return true;
+			$fileId = $this->getNode()->getId();
+			$mounts = $this->userMountCache->getMountsForFileId($fileId);
+			foreach ($mounts as $mount) {
+				if ($mount->getUser()->getUID() !== $uid) {
+					continue;
+				}
+
+				$userFolder = $this->root->getUserFolder($uid);
+				if (!empty($userFolder->getById($fileId))) {
+					return true;
+				}
 			}
-			$acl = $this->shareManager->getAccessList($node, true, true);
-			return isset($acl['users']) && array_key_exists($uid, $acl['users']);
+			return false;
 		} catch (NotFoundException $e) {
 			return false;
 		}