TF-2502 Write unit test for all day event

lib/features/email/presentation/extensions/calendar_event_extension.dart

@@ -272,21 +272,53 @@ extension CalendarEventExtension on CalendarEvent {
     );
   }
 
-  String get dateTimeEventAsString {
+  bool get isAllDayEvent {
     if (startUtcDate != null && endUtcDate != null) {
-      final startHour = startUtcDate!.value.hour;
+      final startDateValue = startUtcDate!.value;
-      final startMinute = startUtcDate!.value.minute;
+      final endDateValue = endUtcDate!.value;
-      final endHour = endUtcDate!.value.hour;
+
-      final endMinute = endUtcDate!.value.minute;
+      final eventDurationInHours = startDateValue.difference(endDateValue).inHours;
-      log('CalendarEventExtension::endDate: $endUtcDate');
+
-      if (startHour == 0 && startMinute == 0 && endHour == 0 && endMinute == 0 && !DateUtils.isSameDay(localStartDate, localEndDate)) {
+      final startHour = startDateValue.hour;
-        final timeZoneOffset = DateTime.now().timeZoneOffset.inHours;
+      final startMinute = startDateValue.minute;
-        final timeZoneOffsetAsString = timeZoneOffset >= 0 ? '+$timeZoneOffset' : '$timeZoneOffset';
+      final startSecond = startDateValue.second;
-        final timeStart = formatDate(AppUtils.getCurrentDateLocale(), startUtcDate!.value);
+      
-        final timeEnd = formatDate(AppUtils.getCurrentDateLocale(), endUtcDate!.value);
+      final endHour = endDateValue.hour;
-        return '$timeStart - $timeEnd (GMT$timeZoneOffsetAsString)';
+      final endMinute = endDateValue.minute;
-      }
+      final endSecond = endDateValue.second;
+
+      return startHour == 0 
+        && startMinute == 0
+        && startSecond == 0
+        && endHour == 0
+        && endMinute == 0
+        && endSecond == 0
+        && eventDurationInHours % 24 == 0;
     }
+    return false;
+  }
+
+  String dateTimeStringForAllDayEvent(DateTime startDate, DateTime endDate) {
+    final timeZoneOffset = DateTime.now().timeZoneOffset.inHours;
+    final timeZoneOffsetAsString = timeZoneOffset >= 0 ? '+$timeZoneOffset' : '$timeZoneOffset';
+
+    final dateStart = formatDate(AppUtils.getCurrentDateLocale(), startDate);
+
+    final endDateToDisplay = endDate.subtract(const Duration(days: 1));
+    final dateEnd = formatDate(AppUtils.getCurrentDateLocale(), endDateToDisplay);
+
+    if (DateUtils.isSameDay(startDate, endDateToDisplay)) {
+      return '$dateStart (GMT$timeZoneOffsetAsString)';
+    } else {
+      return '$dateStart - $dateEnd (GMT$timeZoneOffsetAsString)';
+    }
+  }
+
+  String get dateTimeEventAsString {
+    if (isAllDayEvent) {
+      return dateTimeStringForAllDayEvent(startUtcDate!.value, endUtcDate!.value);
+    }
+
     if (localStartDate != null && localEndDate != null) {
       final timeStart = formatDateTime(localStartDate!);
       final timeEnd = DateUtils.isSameDay(localStartDate, localEndDate)

test/features/features/email/presentation/extensions/calendar_event_extension_test.dart

@@ -0,0 +1,44 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:jmap_dart_client/jmap/core/utc_date.dart';
+import 'package:jmap_dart_client/jmap/mail/calendar/calendar_event.dart';
+import 'package:tmail_ui_user/features/email/presentation/extensions/calendar_event_extension.dart';
+
+void main() {
+  group('calendar event extension test', () {
+    test('dateTimeEventAsString should return string with format start date - end date (timezone offset) and date formatted as DD, MM dd, YYYY for all-day event for many days', () {
+      const expectedFormattedDateString = 'Sunday, October 10, 2021 - Sunday, October 24, 2021 (GMT+0)';
+
+      final startDate = DateTime(2021, 10, 10, 00, 00, 00, 00, 00);
+      final endDate = DateTime(2021, 10, 25, 00, 00, 00, 00, 00);
+
+      final calendarEvent = CalendarEvent(
+        startDate: startDate,
+        endDate: endDate,
+        startUtcDate: UTCDate(startDate),
+        endUtcDate: UTCDate(endDate),
+      );
+
+      final formattedDateString = calendarEvent.dateTimeEventAsString;
+
+      expect(formattedDateString, expectedFormattedDateString);
+    });
+
+    test('dateTimeEventAsString should return string with format date (timezone offset) and date formatted as DD, MM dd, YYYY for all-day event for one day', () {
+      const expectedFormattedDateString = 'Sunday, October 10, 2021 (GMT+0)';
+
+      final startDate = DateTime(2021, 10, 10, 00, 00, 00, 00, 00);
+      final endDate = DateTime(2021, 10, 11, 00, 00, 00, 00, 00);
+
+      final calendarEvent = CalendarEvent(
+        startDate: startDate,
+        endDate: endDate,
+        startUtcDate: UTCDate(startDate),
+        endUtcDate: UTCDate(endDate),
+      );
+
+      final formattedDateString = calendarEvent.dateTimeEventAsString;
+
+      expect(formattedDateString, expectedFormattedDateString);
+    });
+  });
+}