2 files changed, 31 insertions, 3 deletions
diff --git a/lib/private/App/AppManager.php b/lib/private/App/AppManager.php
index f6494fa946d..4223d09e3dc 100644
--- a/lib/private/App/AppManager.php
+++ b/lib/private/App/AppManager.php
@@ -18,6 +18,7 @@ use OCP\Collaboration\AutoComplete\IManager as IAutoCompleteManager;
 use OCP\Collaboration\Collaborators\ISearch as ICollaboratorSearch;
 use OCP\Diagnostics\IEventLogger;
 use OCP\EventDispatcher\IEventDispatcher;
+use OCP\IAppConfig;
 use OCP\ICacheFactory;
 use OCP\IConfig;
 use OCP\IGroup;
@@ -134,7 +135,8 @@ class AppManager implements IAppManager {
 	 */
 	private function getEnabledAppsValues(): array {
 		if (!$this->enabledAppsCache) {
-			$values = $this->getAppConfig()->getValues(false, 'enabled');
+			/** @var array<string,string> */
+			$values = $this->getAppConfig()->searchValues('enabled', false, IAppConfig::VALUE_STRING);
 
 			$alwaysEnabledApps = $this->getAlwaysEnabledApps();
 			foreach ($alwaysEnabledApps as $appId) {
@@ -545,11 +547,16 @@ class AppManager implements IAppManager {
 	 * @param string $appId
 	 * @param bool $forceEnable
 	 * @throws AppPathNotFoundException
+	 * @throws \InvalidArgumentException if the application is not installed yet
 	 */
 	public function enableApp(string $appId, bool $forceEnable = false): void {
 		// Check if app exists
 		$this->getAppPath($appId);
 
+		if ($this->config->getAppValue($appId, 'installed_version', '') === '') {
+			throw new \InvalidArgumentException("$appId is not installed, cannot be enabled.");
+		}
+
 		if ($forceEnable) {
 			$this->overwriteNextcloudRequirement($appId);
 		}
@@ -596,6 +603,10 @@ class AppManager implements IAppManager {
 			throw new \InvalidArgumentException("$appId can't be enabled for groups.");
 		}
 
+		if ($this->config->getAppValue($appId, 'installed_version', '') === '') {
+			throw new \InvalidArgumentException("$appId is not installed, cannot be enabled.");
+		}
+
 		if ($forceEnable) {
 			$this->overwriteNextcloudRequirement($appId);
 		}
@@ -775,8 +786,8 @@ class AppManager implements IAppManager {
 	 *
 	 * @return array<string, string>
 	 */
-	public function getAppInstalledVersions(): array {
-		return $this->getAppConfig()->getAppInstalledVersions();
+	public function getAppInstalledVersions(bool $onlyEnabled = false): array {
+		return $this->getAppConfig()->getAppInstalledVersions($onlyEnabled);
 	}
 
 	/**
@@ -812,6 +823,10 @@ class AppManager implements IAppManager {
 	}
 
 	private function isAlwaysEnabled(string $appId): bool {
+		if ($appId === 'core') {
+			return true;
+		}
+
 		$alwaysEnabled = $this->getAlwaysEnabledApps();
 		return in_array($appId, $alwaysEnabled, true);
 	}
diff --git a/lib/private/App/AppStore/AppNotFoundException.php b/lib/private/App/AppStore/AppNotFoundException.php
new file mode 100644
index 00000000000..79ceebb4423
--- /dev/null
+++ b/lib/private/App/AppStore/AppNotFoundException.php
@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OC\App\AppStore;
+
+class AppNotFoundException extends \Exception {
+}