From 0ea7ec6acfe5ca7680701e4a77f1f87f6f813852 Mon Sep 17 00:00:00 2001
From: Manuel Cillero <manuel@cillero.es>
Date: Thu, 14 Sep 2017 20:02:42 +0200
Subject: [PATCH] Fixed validation error with empty dates

---
 modules/storm/storm.module | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/modules/storm/storm.module b/modules/storm/storm.module
index 23bcc81..51ec60b 100644
--- a/modules/storm/storm.module
+++ b/modules/storm/storm.module
@@ -2410,15 +2410,20 @@ function storm_dateext_validate($element, &$form_state) {
       $format_match = str_replace('/', '\/', $format_match);
       preg_match("/$format_match/", $element['#value']['popup']['date'], $matches);
 
-      $format = str_replace(array('/', '-'), '', $format);
-      $pos_d = max(strpos($format, 'd'), strpos($format, 'j')) + 1;
-      $pos_m = max(strpos($format, 'm'), strpos($format, 'M')) + 1;
-      $pos_y = strpos($format, 'Y') + 1;
+      if (empty($matches)) {
+        $element['#value'] = array('day' => -1, 'month' => -1, 'year' => -1);
+      }
+      else {
+        $format = str_replace(array('/', '-'), '', $format);
+        $pos_d = max(strpos($format, 'd'), strpos($format, 'j')) + 1;
+        $pos_m = max(strpos($format, 'm'), strpos($format, 'M')) + 1;
+        $pos_y = strpos($format, 'Y') + 1;
 
-      $element['#value'] = array();
-      $element['#value']['day'] = (int) $matches[$pos_d];
-      $element['#value']['month'] = (int) $matches[$pos_m];
-      $element['#value']['year'] = (int) $matches[$pos_y];
+        $element['#value'] = array();
+        $element['#value']['day'] = (int) $matches[$pos_d];
+        $element['#value']['month'] = (int) $matches[$pos_m];
+        $element['#value']['year'] = (int) $matches[$pos_y];
+      }
     }
     else {
       if (!$element['#withnull'] && !empty($element['#value']['popup']['date'])) {