Calendar trigger: Handle optional offset better (#23474)

Calendar empty offset

src/data/automation_i18n.ts

@@ -737,18 +737,22 @@ const tryDescribeTrigger = (
       ? computeStateName(hass.states[trigger.entity_id])
       : trigger.entity_id;
 
-    let offsetChoice = trigger.offset.startsWith("-") ? "before" : "after";
-    let offset: string | string[] = trigger.offset.startsWith("-")
-      ? trigger.offset.substring(1).split(":")
-      : trigger.offset.split(":");
-    const duration = {
-      hours: offset.length > 0 ? +offset[0] : 0,
-      minutes: offset.length > 1 ? +offset[1] : 0,
-      seconds: offset.length > 2 ? +offset[2] : 0,
-    };
-    offset = formatDurationLong(hass.locale, duration);
-    if (offset === "") {
-      offsetChoice = "other";
+    let offsetChoice: string = "other";
+    let offset: string | string[] = "";
+    if (trigger.offset) {
+      offsetChoice = trigger.offset.startsWith("-") ? "before" : "after";
+      offset = trigger.offset.startsWith("-")
+        ? trigger.offset.substring(1).split(":")
+        : trigger.offset.split(":");
+      const duration = {
+        hours: offset.length > 0 ? +offset[0] : 0,
+        minutes: offset.length > 1 ? +offset[1] : 0,
+        seconds: offset.length > 2 ? +offset[2] : 0,
+      };
+      offset = formatDurationLong(hass.locale, duration);
+      if (offset === "") {
+        offsetChoice = "other";
+      }
     }
 
     return hass.localize(