From d8d65ed415f67e18267b34d99c6aed2a6f13e2f6 Mon Sep 17 00:00:00 2001
From: Naveen <snaveen935@gmail.com>
Date: Mon, 2 Oct 2023 17:33:08 +0530
Subject: [PATCH] Properly calculate weekly day codes from start week timestamp

Because start week timestamp is in local timezone, just adding 86400 is not correct in regions with daylight savings time. See https://github.com/SimpleMobileTools/Simple-Calendar/issues/2211
---
 .../calendar/pro/fragments/WeekFragment.kt             | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/app/src/main/kotlin/com/simplemobiletools/calendar/pro/fragments/WeekFragment.kt b/app/src/main/kotlin/com/simplemobiletools/calendar/pro/fragments/WeekFragment.kt
index 691a19798..c83d1b4be 100644
--- a/app/src/main/kotlin/com/simplemobiletools/calendar/pro/fragments/WeekFragment.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/calendar/pro/fragments/WeekFragment.kt
@@ -48,6 +48,7 @@ class WeekFragment : Fragment(), WeeklyCalendar {
 
     var listener: WeekFragmentListener? = null
     private var weekTimestamp = 0L
+    private var weekDateTime = DateTime()
     private var rowHeight = 0f
     private var todayColumnIndex = -1
     private var primaryColor = 0
@@ -91,6 +92,7 @@ class WeekFragment : Fragment(), WeeklyCalendar {
         rowHeight = requireContext().getWeeklyViewItemHeight()
         defaultRowHeight = res.getDimension(R.dimen.weekly_view_row_height)
         weekTimestamp = requireArguments().getLong(WEEK_START_TIMESTAMP)
+        weekDateTime = Formatter.getDateTimeFromTS(weekTimestamp)
         dimPastEvents = config.dimPastEvents
         dimCompletedTasks = config.dimCompletedTasks
         highlightWeekends = config.highlightWeekends
@@ -193,14 +195,14 @@ class WeekFragment : Fragment(), WeeklyCalendar {
         binding.weekEventsColumnsHolder.removeAllViews()
         (0 until config.weeklyViewDays).forEach {
             val column = WeeklyViewDayColumnBinding.inflate(layoutInflater, binding.weekEventsColumnsHolder, false).root
-            column.tag = Formatter.getDayCodeFromTS(weekTimestamp + it * DAY_SECONDS)
+            column.tag = Formatter.getDayCodeFromDateTime(weekDateTime.plusDays(it))
             binding.weekEventsColumnsHolder.addView(column)
             dayColumns.add(column)
         }
     }
 
     private fun setupDayLabels() {
-        var curDay = Formatter.getDateTimeFromTS(weekTimestamp)
+        var curDay = weekDateTime
         val todayCode = Formatter.getDayCodeFromDateTime(DateTime())
         val screenWidth = context?.usableScreenSize?.x ?: return
         val dayWidth = screenWidth / config.weeklyViewDays
@@ -273,7 +275,7 @@ class WeekFragment : Fragment(), WeeklyCalendar {
                                     val event = context?.eventsDB?.getEventOrTaskWithId(eventId)
                                     event?.let {
                                         val currentStartTime = Formatter.getDateTimeFromTS(event.startTS)
-                                        val startTime = Formatter.getDateTimeFromTS(weekTimestamp + index * DAY_SECONDS)
+                                        val startTime = weekDateTime.plusDays(index)
                                             .withTime(
                                                 startHour,
                                                 currentStartTime.minuteOfHour,
@@ -364,7 +366,7 @@ class WeekFragment : Fragment(), WeeklyCalendar {
                     applyColorFilter(primaryColor.getContrastColor())
 
                     setOnClickListener {
-                        val timestamp = Formatter.getDateTimeFromTS(weekTimestamp + index * DAY_SECONDS).withTime(hour, 0, 0, 0).seconds()
+                        val timestamp = weekDateTime.plusDays(index).withTime(hour, 0, 0, 0).seconds()
                         if (config.allowCreatingTasks) {
                             val items = arrayListOf(
                                 RadioItem(TYPE_EVENT, getString(R.string.event)),