feat(archiving): add mapper support for archive override cleanup

Add UserArchiveMapper::findUserIdsForNode() and deleteAllForUser(),
plus ShareMapper::findNodesByReceiver(), as building blocks for
cleaning up per-user archive overrides when access is lost.

Assisted-by: ClaudeCode:claude-fable-5
Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

Author: AndyScherzinger

lib/Db/ShareMapper.php

@@ -301,6 +301,28 @@ public function changeReceiverForNode(string $nodeType, int $nodeId, string $new
 			->executeStatement();
 	}
 
+	/**
+	 * Find the distinct nodes shared with a given receiver.
+	 *
+	 * @return list<array{nodeType: string, nodeId: int}>
+	 * @throws Exception
+	 */
+	public function findNodesByReceiver(string $receiver, string $receiverType): array {
+		$qb = $this->db->getQueryBuilder();
+		$qb->selectDistinct(['node_type', 'node_id'])
+			->from($this->table)
+			->where($qb->expr()->eq('receiver', $qb->createNamedParameter($receiver, IQueryBuilder::PARAM_STR)))
+			->andWhere($qb->expr()->eq('receiver_type', $qb->createNamedParameter($receiverType, IQueryBuilder::PARAM_STR)));
+
+		$result = $qb->executeQuery();
+		$nodes = [];
+		while ($row = $result->fetchAssociative()) {
+			$nodes[] = ['nodeType' => (string)$row['node_type'], 'nodeId' => (int)$row['node_id']];
+		}
+		$result->closeCursor();
+		return $nodes;
+	}
+
 	/**
 	 * @throws Exception
 	 */

lib/Db/UserArchiveMapper.php

@@ -97,6 +97,41 @@ public function upsert(string $userId, int $nodeType, int $nodeId, bool $archive
 		]);
 	}
 
+	/**
+	 * Fetch the IDs of all users holding an archive override for a node.
+	 *
+	 * @return string[]
+	 * @throws Exception
+	 */
+	public function findUserIdsForNode(int $nodeType, int $nodeId): array {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select('user_id')
+			->from($this->table)
+			->where($qb->expr()->eq('node_type', $qb->createNamedParameter($nodeType, IQueryBuilder::PARAM_INT)))
+			->andWhere($qb->expr()->eq('node_id', $qb->createNamedParameter($nodeId, IQueryBuilder::PARAM_INT)));
+
+		$result = $qb->executeQuery();
+		$userIds = array_map(static fn (array $row) => (string)$row['user_id'], $result->fetchAllAssociative());
+		$result->closeCursor();
+		return $userIds;
+	}
+
+	/**
+	 * Remove every archive override a user holds, on any node.
+	 *
+	 * Called when the user account is deleted, so no orphaned rows remain
+	 * for nodes owned by other users.
+	 *
+	 * @throws Exception
+	 */
+	public function deleteAllForUser(string $userId): void {
+		$qb = $this->db->getQueryBuilder();
+		$qb->delete($this->table)
+			->where($qb->expr()->eq('user_id', $qb->createNamedParameter($userId, IQueryBuilder::PARAM_STR)));
+
+		$qb->executeStatement();
+	}
+
 	/**
 	 * Remove the per-user archive override for a single user.
 	 *

tests/unit/Db/UserArchiveMapperTest.php

@@ -148,6 +148,43 @@ public function testFindAllOverridesForUserIgnoresOtherNodeTypes(): void {
 		$this->assertEmpty($results);
 	}
 
+	// -------------------------------------------------------------------------
+	// findUserIdsForNode
+	// -------------------------------------------------------------------------
+
+	public function testFindUserIdsForNodeReturnsAllHolders(): void {
+		$this->mapper->upsert('alice', Application::NODE_TYPE_TABLE, 5, true);
+		$this->mapper->upsert('bob', Application::NODE_TYPE_TABLE, 5, false);
+		$this->mapper->upsert('carol', Application::NODE_TYPE_TABLE, 6, true);
+
+		$userIds = $this->mapper->findUserIdsForNode(Application::NODE_TYPE_TABLE, 5);
+
+		sort($userIds);
+		$this->assertSame(['alice', 'bob'], $userIds);
+	}
+
+	public function testFindUserIdsForNodeReturnsEmptyWhenNone(): void {
+		$this->assertSame([], $this->mapper->findUserIdsForNode(Application::NODE_TYPE_TABLE, 999));
+	}
+
+	// -------------------------------------------------------------------------
+	// deleteAllForUser
+	// -------------------------------------------------------------------------
+
+	public function testDeleteAllForUserRemovesAllNodesAndTypes(): void {
+		$this->mapper->upsert('alice', Application::NODE_TYPE_TABLE, 1, true);
+		$this->mapper->upsert('alice', Application::NODE_TYPE_TABLE, 2, false);
+		$this->mapper->upsert('alice', Application::NODE_TYPE_CONTEXT, 3, true);
+		$this->mapper->upsert('bob', Application::NODE_TYPE_TABLE, 1, true);
+
+		$this->mapper->deleteAllForUser('alice');
+
+		$this->assertNull($this->mapper->findForUser('alice', Application::NODE_TYPE_TABLE, 1));
+		$this->assertNull($this->mapper->findForUser('alice', Application::NODE_TYPE_TABLE, 2));
+		$this->assertNull($this->mapper->findForUser('alice', Application::NODE_TYPE_CONTEXT, 3));
+		$this->assertNotNull($this->mapper->findForUser('bob', Application::NODE_TYPE_TABLE, 1));
+	}
+
 	// -------------------------------------------------------------------------
 	// deleteForUser
 	// -------------------------------------------------------------------------