make RangeConfig always return typed classes, fixes #6191

Closes #6191

Merge request studip/studip!4689

1 files changed, 31 insertions, 6 deletions

diff --git a/lib/classes/RangeConfig.class.php b/lib/classes/RangeConfig.class.php
index b1030e3..52d3ac0 100644
--- a/lib/classes/RangeConfig.class.php
+++ b/lib/classes/RangeConfig.class.php
@@ -15,8 +15,15 @@
  * @category    Stud.IP
 */
 
-class RangeConfig extends Config
+abstract class RangeConfig extends Config
 {
+    private static array $range_mapping = [
+        'sem'  => CourseConfig::class,
+        'user' => UserConfig::class,
+        'fak'  => InstituteConfig::class,
+        'inst' => InstituteConfig::class,
+    ];
+
     /**
      * range type
      */
@@ -24,9 +31,9 @@ class RangeConfig extends Config
 
     /**
      * cache of created RangeConfig instances
-     * @var array
+     * @var array<string, static>
      */
-    protected static $instances = [];
+    private static array $instances = [];
 
     /**
      * range_id
@@ -52,10 +59,28 @@ class RangeConfig extends Config
             $range_id = $range_id->getRangeId();
         }
 
-        if (!isset(static::$instances[$range_id])) {
-            static::$instances[$range_id] = new static($range_id);
+        $type = get_object_type($range_id, array_keys(self::$range_mapping));
+        if (self::class === static::class) {
+            // Detect correct class for range
+            if (!$type) {
+                throw new InvalidArgumentException('Invalid range_id given');
+            }
+
+            $class_name = self::$range_mapping[$type];
+        } else {
+            // Prevent type mismatches (allow non existing ids)
+            if (
+                $type
+                && !in_array($type, array_keys(self::$range_mapping, static::class))
+            ) {
+                throw new InvalidArgumentException('Invalid range_id given');
+            }
+
+            $class_name = static::class;
         }
-        return static::$instances[$range_id];
+
+        return self::$instances[$range_id]
+            ??= new $class_name($range_id);
     }
 
     /**