emm - use string instead of date for start/endDate

components/book/dateSelect.tsx

@@ -15,8 +15,8 @@ export default function DateSelect() {
     <>
       <InputWrapper label="Datum" required>
         <Calendar
-          start={dateFormatBackend(startDate)}
-          end={dateFormatBackend(endDate)}
+          start={startDate}
+          end={endDate}
           onChange={onChange}
           className="my-6 max-w-lg"
         />
@@ -28,7 +28,7 @@ export default function DateSelect() {
             type="date"
             className=""
             name="startDate"
-            value={dateFormatBackend(startDate) || ''}
+            value={startDate || ''}
             onChange={onChangeEvent}
             min={today}
             required
@@ -41,10 +41,10 @@ export default function DateSelect() {
             type="date"
             className=""
             name="endDate"
-            value={dateFormatBackend(endDate) || ''}
+            value={endDate || ''}
             placeholder="Von"
             onChange={onChangeEvent}
-            min={dateFormatBackend(startDate) || today}
+            min={startDate || today}
           />
         </div>
       </div>

components/calendar.tsx

@@ -107,6 +107,8 @@ export default function MyCalendar({
               return
             }
 
+            const dateAsBackendFormat = dateFormatBackend(date);
+
             event.preventDefault()
             event.stopPropagation()
 
@@ -122,15 +124,15 @@ export default function MyCalendar({
 
             // when startDate missing or both are already set
             if (!startDate || (!!startDate && !!endDate)) {
-              onChange({ startDate: date, endDate: null })
+              onChange({ startDate: dateAsBackendFormat, endDate: null })
               return
             }
 
             // when startDate set, but end missing
             if (isAfter(date, startDate)) {
-              onChange({ endDate: date })
+              onChange({ endDate: dateAsBackendFormat })
             } else {
-              onChange({ startDate: date, endDate: date })
+              onChange({ startDate: dateAsBackendFormat, endDate: dateAsBackendFormat })
             }
           }}
           tileClassName={tileClassName}