3 files changed, 107 insertions, 0 deletions
diff --git a/lib/public/Template/ITemplate.php b/lib/public/Template/ITemplate.php
new file mode 100644
index 00000000000..7131df4d17c
--- /dev/null
+++ b/lib/public/Template/ITemplate.php
@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCP\Template;
+
+/**
+ * @since 32.0.0
+ */
+interface ITemplate {
+	/**
+	 * Process the template
+	 * @since 32.0.0
+	 */
+	public function fetchPage(?array $additionalParams = null): string;
+
+	/**
+	 * Proceed the template and print its output.
+	 * @since 32.0.0
+	 */
+	public function printPage(): void;
+
+	/**
+	 * Assign variables
+	 *
+	 * This function assigns a variable. It can be accessed via $_[$key] in
+	 * the template.
+	 *
+	 * If the key existed before, it will be overwritten
+	 * @since 32.0.0
+	 */
+	public function assign(string $key, mixed $value): void;
+
+	/**
+	 * Appends a variable
+	 *
+	 * This function assigns a variable in an array context. If the key already
+	 * exists, the value will be appended. It can be accessed via
+	 * $_[$key][$position] in the template.
+	 */
+	public function append(string $key, mixed $value): void;
+}
diff --git a/lib/public/Template/ITemplateManager.php b/lib/public/Template/ITemplateManager.php
new file mode 100644
index 00000000000..05549bbddfd
--- /dev/null
+++ b/lib/public/Template/ITemplateManager.php
@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCP\Template;
+
+use OCP\AppFramework\Http\TemplateResponse;
+
+/**
+ * @since 32.0.0
+ */
+interface ITemplateManager {
+	/**
+	 * @param TemplateResponse::RENDER_AS_* $renderAs
+	 * @throws TemplateNotFoundException if the template cannot be found
+	 * @since 32.0.0
+	 */
+	public function getTemplate(string $app, string $name, string $renderAs = TemplateResponse::RENDER_AS_BLANK, bool $registerCall = true): ITemplate;
+
+	/**
+	 * Shortcut to print a simple page for guests
+	 * @since 32.0.0
+	 */
+	public function printGuestPage(string $application, string $name, array $parameters = []): void;
+
+	/**
+	 * Print a fatal error page and terminates the script
+	 * @since 32.0.0
+	 * @param string $error_msg The error message to show
+	 * @param string $hint An optional hint message - needs to be properly escape
+	 */
+	public function printErrorPage(string $error_msg, string $hint = '', int $statusCode = 500): never;
+
+	/**
+	 * Print error page using Exception details
+	 * @since 32.0.0
+	 */
+	public function printExceptionErrorPage(\Throwable $exception, int $statusCode = 503): never;
+}
diff --git a/lib/public/Template/TemplateNotFoundException.php b/lib/public/Template/TemplateNotFoundException.php
new file mode 100644
index 00000000000..e77fcd8646a
--- /dev/null
+++ b/lib/public/Template/TemplateNotFoundException.php
@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCP\Template;
+
+/**
+ * @since 32.0.0
+ */
+class TemplateNotFoundException extends \Exception {
+}