Implement Tobi feedback

Author: vmcj

webapp/src/Entity/Contest.php

@@ -1260,15 +1260,10 @@ public function getFreezeData(): FreezeData
         return new FreezeData($this);
     }
 
-    public function checkValidTimeString(string $timeString): bool {
+    public function checkValidTimeString(string $timeString): void {
         if (preg_match("/^[+-]?\d+:\d\d(:\d\d(\.\d{1,6})?)?$/", $timeString) !== 1) {
-            try {
-                $date = new DateTime($timeString);
-            } catch (Exception) {
-                return false;
-            }
+            $date = new DateTime($timeString);
         }
-        return true;
     }
 
     #[ORM\PrePersist]
@@ -1286,9 +1281,11 @@ public function validate(ExecutionContextInterface $context): void
         foreach (['Activate', 'Deactivate', 'Start', 'End', 'Freeze', 'Unfreeze'] as $timeString) {
             $tmpValue = $this->{'get' . $timeString . 'timeString'}();
             if ($tmpValue === null) continue;
-            if (!$this->checkValidTimeString($tmpValue)) {
+            try {
+                $this->checkValidTimeString($tmpValue))
+            } catch (Exception $e) {
                 $context
-                    ->buildViolation("Can't parse this time.")
+                    ->buildViolation("Can't parse this time," . $e->message)
                     ->atPath(strtolower($timeString) . "timeString")
                     ->addViolation();
             }