From ea78b1c2df4f655c571f872e66e489e6ae531d11 Mon Sep 17 00:00:00 2001
From: Aleksander Machniak <machniak@kolabsys.com>
Date: Fri, 17 Dec 2021 11:26:48 +0100
Subject: [PATCH] Display original time and timezone in iTip info box

---
 plugins/calendar/calendar.php                 | 16 +++--
 .../lib/libcalendaring_itip.php               |  2 +-
 plugins/libcalendaring/libcalendaring.php     | 59 ++++++++++++-------
 3 files changed, 51 insertions(+), 26 deletions(-)

diff --git a/plugins/calendar/calendar.php b/plugins/calendar/calendar.php
index 475f1bfa..eea9cfd6 100644
--- a/plugins/calendar/calendar.php
+++ b/plugins/calendar/calendar.php
@@ -3149,10 +3149,16 @@ $("#rcmfd_new_category").keypress(function(event) {
      */
     private function mail_agenda_event_row($event, $class = '')
     {
-        $time = !empty($event['allday']) ? $this->gettext('all-day') :
-            $this->rc->format_date($event['start'], $this->rc->config->get('time_format'))
-            . ' - ' .
-            $this->rc->format_date($event['end'], $this->rc->config->get('time_format'));
+        if (!empty($event['allday'])) {
+            $time = $this->gettext('all-day');
+        }
+        else {
+            $start = is_object($event['start']) ? clone $event['start'] : $event['start'];
+            $end = is_object($event['end']) ? clone $event['end'] : $event['end'];
+
+            $time = $this->rc->format_date($start, $this->rc->config->get('time_format'))
+                . ' - ' . $this->rc->format_date($end, $this->rc->config->get('time_format'));
+        }
 
         return html::div(rtrim('event-row ' . ($class ?: $event['className'])),
             html::span('event-date', $time)
@@ -3217,7 +3223,7 @@ $("#rcmfd_new_category").keypress(function(event) {
             // get prepared inline UI for this event object
             if ($ical_objects->method) {
                 $append   = '';
-                $date_str = $this->rc->format_date($event['start'], $this->rc->config->get('date_format'), empty($event['start']->_dateonly));
+                $date_str = $this->rc->format_date(clone $event['start'], $this->rc->config->get('date_format'), empty($event['start']->_dateonly));
                 $date     = new DateTime($event['start']->format('Y-m-d') . ' 12:00:00', new DateTimeZone('UTC'));
 
                 // prepare a small agenda preview to be filled with actual event data on async request
diff --git a/plugins/libcalendaring/lib/libcalendaring_itip.php b/plugins/libcalendaring/lib/libcalendaring_itip.php
index 93e0a26e..1338a56c 100644
--- a/plugins/libcalendaring/lib/libcalendaring_itip.php
+++ b/plugins/libcalendaring/lib/libcalendaring_itip.php
@@ -136,7 +136,7 @@ class libcalendaring_itip
             'name' => $bodytext,
             'vars' => array(
                 'title'       => $event['title'],
-                'date'        => $this->lib->event_date_text($event, true) . $recurrence_info,
+                'date'        => $this->lib->event_date_text($event) . $recurrence_info,
                 'attendees'   => join(",\n ", $attendees_list),
                 'sender'      => $this->sender['name'],
                 'organizer'   => $this->sender['name'],
diff --git a/plugins/libcalendaring/libcalendaring.php b/plugins/libcalendaring/libcalendaring.php
index c98325ec..426f6f48 100644
--- a/plugins/libcalendaring/libcalendaring.php
+++ b/plugins/libcalendaring/libcalendaring.php
@@ -288,19 +288,43 @@ class libcalendaring extends rcube_plugin
     /**
      * Compose a date string for the given event
      */
-    public function event_date_text($event, $tzinfo = false)
+    public function event_date_text($event)
     {
         $fromto  = '--';
         $is_task = !empty($event['_type']) && $event['_type'] == 'task';
 
+        $this->date_format_defaults();
+
+        $date_format = self::to_php_date_format($this->rc->config->get('calendar_date_format', $this->defaults['calendar_date_format']));
+        $time_format = self::to_php_date_format($this->rc->config->get('calendar_time_format', $this->defaults['calendar_time_format']));
+
+        $getTimezone = function ($date) {
+            if ($newTz = $date->getTimezone()) {
+                return $newTz->getName();
+            }
+
+            return '';
+        };
+
+        $formatDate = function ($date, $format) use ($getTimezone) {
+            // This is a workaround for the rcmail::format_date() which does not play nice with timezone
+            $tz = $this->rc->config->get('timezone');
+            if ($dateTz = $getTimezone($date)) {
+                $this->rc->config->set('timezone', $dateTz);
+            }
+            $result = $this->rc->format_date($date, $format);
+            $this->rc->config->set('timezone', $tz);
+
+            return $result;
+        };
+
         // handle task objects
         if ($is_task && !empty($event['due']) && is_object($event['due'])) {
-            $date_format = !empty($event['due']->_dateonly) ? self::to_php_date_format($this->rc->config->get('calendar_date_format', $this->defaults['calendar_date_format'])) : null;
-            $fromto = $this->rc->format_date($event['due'], $date_format, false);
+            $fromto = $formatDate($event['due'], !empty($event['due']->_dateonly) ? $date_format : null);
 
             // add timezone information
-            if ($fromto && $tzinfo && ($tzname = $this->timezone->getName())) {
-                $fromto .= ' (' . strtr($tzname, '_', ' ') . ')';
+            if ($fromto && empty($event['due']->_dateonly) && ($tz = $getTimezone($event['due']))) {
+                $fromto .= ' (' . strtr($tz, '_', ' ') . ')';
             }
 
             return $fromto;
@@ -311,29 +335,24 @@ class libcalendaring extends rcube_plugin
             return $fromto;
         }
 
-        $duration = $event['start']->diff($event['end'])->format('s');
-
-        $this->date_format_defaults();
-        $date_format = self::to_php_date_format($this->rc->config->get('calendar_date_format', $this->defaults['calendar_date_format']));
-        $time_format = self::to_php_date_format($this->rc->config->get('calendar_time_format', $this->defaults['calendar_time_format']));
-
         if ($event['allday']) {
-            $fromto = $this->rc->format_date($event['start'], $date_format, false);
-            if (($todate = $this->rc->format_date($event['end'], $date_format, false)) != $fromto)
+            $fromto = $formatDate($event['start'], $date_format);
+            if (($todate = $formatDate($event['end'], $date_format)) != $fromto) {
                 $fromto .= ' - ' . $todate;
+            }
         }
-        else if ($duration < 86400 && $event['start']->format('d') == $event['end']->format('d')) {
-            $fromto = $this->rc->format_date($event['start'], $date_format) . ' ' . $this->rc->format_date($event['start'], $time_format) .
-                ' - ' . $this->rc->format_date($event['end'], $time_format);
+        else if ($event['start']->format('Ymd') === $event['end']->format('Ymd')) {
+            $fromto = $formatDate($event['start'], $date_format) . ' ' . $formatDate($event['start'], $time_format) .
+                ' - ' . $formatDate($event['end'], $time_format);
         }
         else {
-            $fromto = $this->rc->format_date($event['start'], $date_format) . ' ' . $this->rc->format_date($event['start'], $time_format) .
-                ' - ' . $this->rc->format_date($event['end'], $date_format) . ' ' . $this->rc->format_date($event['end'], $time_format);
+            $fromto = $formatDate($event['start'], $date_format) . ' ' . $formatDate($event['start'], $time_format) .
+                ' - ' . $formatDate($event['end'], $date_format) . ' ' . $formatDate($event['end'], $time_format);
         }
 
         // add timezone information
-        if ($tzinfo && ($tzname = $this->timezone->getName())) {
-            $fromto .= ' (' . strtr($tzname, '_', ' ') . ')';
+        if ($fromto && empty($event['allday']) && ($tz = $getTimezone($event['start']))) {
+            $fromto .= ' (' . strtr($tz, '_', ' ') . ')';
         }
 
         return $fromto;