From f48da0c0d0cb8a0f612a67c53a6fa5ca8592f5e6 Mon Sep 17 00:00:00 2001
From: Thibeau Fuhrer <thibeau@sr.solutions>
Date: Mon, 25 Nov 2024 11:22:30 +0100
Subject: [PATCH] [FIX] UI: properly count inputs of Field\HasDynamicInputs
 templates. (#8422)

---
 .../js/Input/Field/dynamic_inputs_renderer.js | 21 ++++++++++++++-----
 .../Component/Input/Field/Renderer.php        | 19 ++++++++++++++++-
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/components/ILIAS/UI/resources/js/Input/Field/dynamic_inputs_renderer.js b/components/ILIAS/UI/resources/js/Input/Field/dynamic_inputs_renderer.js
index 168c2ec68cd0..6a5fa18bb310 100755
--- a/components/ILIAS/UI/resources/js/Input/Field/dynamic_inputs_renderer.js
+++ b/components/ILIAS/UI/resources/js/Input/Field/dynamic_inputs_renderer.js
@@ -1,4 +1,19 @@
 /**
+ * This file is part of ILIAS, a powerful learning management system
+ * published by ILIAS open source e-Learning e.V.
+ *
+ * ILIAS is licensed with the GPL-3.0,
+ * see https://www.gnu.org/licenses/gpl-3.0.en.html
+ * You should have received a copy of said license along with the
+ * source code, too.
+ *
+ * If this is not the case or you just want to try ILIAS, you'll find
+ * us at:
+ * https://www.ilias.de
+ * https://github.com/ILIAS-eLearning
+ *
+ * *******************************************************************
+ *
  * this script is responsible for clientside rendering of Inputs
  * ILIAS\UI\Component\Input\Field\DynamicInputsAware.
  *
@@ -82,13 +97,9 @@ il.UI.Input = il.UI.Input || {};
      * @param {int} sub_input_count
      */
     let addInputTemplateIds = function (template_html, sub_input_count) {
-      if (1 >= sub_input_count) {
-        return replaceAll(template_html, INPUT_ID_PLACEHOLDER, generateId());
-      }
-
       // Ids must not be all the same, therefore we need to generate
       // one for each sub-input contained in the template.
-      for (let i = 0; i < sub_input_count; i++) {
+      for (let i = 0; i <= sub_input_count; i++) {
         template_html = replaceAll(
           template_html,
           `${INPUT_ID_PLACEHOLDER}_${i}`,
diff --git a/components/ILIAS/UI/src/Implementation/Component/Input/Field/Renderer.php b/components/ILIAS/UI/src/Implementation/Component/Input/Field/Renderer.php
index ee1bce23c599..8a3c0266d2fd 100755
--- a/components/ILIAS/UI/src/Implementation/Component/Input/Field/Renderer.php
+++ b/components/ILIAS/UI/src/Implementation/Component/Input/Field/Renderer.php
@@ -960,7 +960,7 @@ protected function initClientsideRenderer(
         string $template_html
     ): FI\HasDynamicInputs {
         $dynamic_inputs_template_html = $this->replaceTemplateIds($template_html);
-        $dynamic_input_count = count($input->getDynamicInputs());
+        $dynamic_input_count = $this->countInputsWithoutGroupsRecursively($input->getTemplateForDynamicInputs());
 
         // note that $dynamic_inputs_template_html is in tilted single quotes (`),
         // because otherwise the html syntax might collide with normal ones.
@@ -980,6 +980,23 @@ protected function initClientsideRenderer(
         });
     }
 
+    /**
+     * Counts all inputs and nested inputs of groups, without counting groups themselves.
+     */
+    protected function countInputsWithoutGroupsRecursively(FormInput|Input $input): int
+    {
+        if (!($input instanceof Component\Input\Group)) {
+            return 1;
+        }
+
+        $count = 0;
+        foreach ($input->getInputs() as $sub_input) {
+            $count += $this->countInputsWithoutGroupsRecursively($sub_input);
+        }
+
+        return $count;
+    }
+
     protected function replaceTemplateIds(string $template_html): string
     {
         // regex matches anything between 'id="' and '"', hence the js_id.