From 580dafe12344efc6bbb7ed279bc1ee3a165d1e68 Mon Sep 17 00:00:00 2001
From: Andreas Schneider <aksdb@gmx.de>
Date: Mon, 2 Apr 2018 12:56:55 +0200
Subject: [PATCH] Added wholeDay updating

---
 src/calanonsync/calanonsync.go |  2 +-
 src/calanonsync/caldav.go      | 38 +++++++++++++++++++++++++++++++---
 src/calanonsync/caldav_test.go | 24 +++++++++++++++++++--
 3 files changed, 58 insertions(+), 6 deletions(-)

diff --git a/src/calanonsync/calanonsync.go b/src/calanonsync/calanonsync.go
index c03073d..3f21ba3 100644
--- a/src/calanonsync/calanonsync.go
+++ b/src/calanonsync/calanonsync.go
@@ -52,7 +52,7 @@ func main() {
 				!ewsItem.End.Equal(calDavItem.End()) {
 
 				// So times have changed. Update.
-				calDavItem.Update(ewsItem.Start, ewsItem.End)
+				calDavItem.Update(ewsItem.Start, ewsItem.End, ewsItem.IsAllDayEvent)
 
 				err := c.UploadItem(calDavItem)
 				if err == nil {
diff --git a/src/calanonsync/caldav.go b/src/calanonsync/caldav.go
index 43554a3..2040e02 100644
--- a/src/calanonsync/caldav.go
+++ b/src/calanonsync/caldav.go
@@ -78,7 +78,39 @@ var fieldMatch = regexp.MustCompile(`^(\w+)[;:]`)
 
 // Update the ical structure with a new start/end time (and the
 // timestamp of the last modification).
-func (ical *ICal) Update(newStart, newEnd time.Time) {
+// If wholeDay is requested, the start and end times are tried
+// first. If they are precisely 0:00 to 0:00, fine. Otherwise
+// they are converted to local timezone and tried again. If that
+// also fails the event is NOT considered whole day!
+func (ical *ICal) Update(newStart, newEnd time.Time, wholeDay bool) {
+	if wholeDay && (newStart.Hour() != 0 || newStart.Minute() != 0 ||
+		newEnd.Hour() != 0 || newEnd.Hour() != 0) {
+
+		newStart = newStart.In(time.Local)
+		newEnd = newEnd.In(time.Local)
+
+		if newStart.Hour() != 0 || newStart.Minute() != 0 ||
+			newEnd.Hour() != 0 || newEnd.Hour() != 0 {
+
+			log.Printf("Cannot update event %s as whole day.\n", ical.UID())
+			wholeDay = false
+		}
+	}
+
+	if wholeDay {
+		// For wholeDay events, the endDate is the beginning of the next day. For
+		// the formatting to work, we need to move that back into the previous day.
+		newEnd = newEnd.Add(-1 * time.Second)
+	}
+
+	formatTime := func(t time.Time) string {
+		if wholeDay {
+			return ";VALUE=DATE:" + t.Format(ICAL_DATE)
+		} else {
+			return ":" + t.UTC().Format(ICAL_TIME) + "Z"
+		}
+	}
+
 	for i, line := range ical.eventData {
 		match := fieldMatch.FindStringSubmatch(line)
 		if match == nil {
@@ -90,9 +122,9 @@ func (ical *ICal) Update(newStart, newEnd time.Time) {
 
 		switch match[1] {
 		case "DTSTART":
-			ical.eventData[i] = "DTSTART:" + newStart.UTC().Format(ICAL_TIME) + "Z"
+			ical.eventData[i] = match[1] + formatTime(newStart)
 		case "DTEND":
-			ical.eventData[i] = "DTEND:" + newEnd.UTC().Format(ICAL_TIME) + "Z"
+			ical.eventData[i] = match[1] + formatTime(newEnd)
 		case "DTSTAMP", "LAST-MODIFIED":
 			ical.eventData[i] = match[1] + ":" + now.Format(ICAL_TIME) + "Z"
 		}
diff --git a/src/calanonsync/caldav_test.go b/src/calanonsync/caldav_test.go
index 3ea4be8..fb4fc45 100644
--- a/src/calanonsync/caldav_test.go
+++ b/src/calanonsync/caldav_test.go
@@ -79,7 +79,7 @@ func TestICal_Update(t *testing.T) {
 
 	t.Run("Values updated", func(t *testing.T) {
 		ical, _ := ParseICal(strings.NewReader(icsSimple))
-		ical.Update(newStart, newEnd)
+		ical.Update(newStart, newEnd, false)
 
 		if ical.Start() != newStart {
 			t.Error("Start not updated correctly")
@@ -92,6 +92,7 @@ func TestICal_Update(t *testing.T) {
 			t.Error("Timestamp doesn't seem to be updated")
 		}
 	})
+
 	t.Run("Other values untouched", func(t *testing.T) {
 		// Use a ICal structure with dummy/unknown fields but also without
 		// DTSTAMP or LAST-MODIFIED, so we can do a string comparison against
@@ -112,7 +113,7 @@ END:VEVENT
 EVEN;MORE:STUFF
 END:VCALENDAR`))
 
-		ical.Update(newStart, newEnd)
+		ical.Update(newStart, newEnd, false)
 
 		if ical.String() != `BEGIN:VCALENDAR
 PRODID:-//some//thing//EN
@@ -133,6 +134,25 @@ END:VCALENDAR` {
 			t.Error("The resulting ICS seems wrong.")
 		}
 	})
+
+	t.Run("Values wholeDay", func(t *testing.T) {
+		newStart := time.Date(2019, 1, 2, 0, 0, 0, 0, time.Local)
+		newEnd := time.Date(2019, 1, 3, 0, 0, 0, 0, time.Local)
+
+		ical, _ := ParseICal(strings.NewReader(icsSimple))
+		ical.Update(newStart, newEnd, true)
+
+		if ical.Start() != newStart {
+			t.Error("Start not updated correctly")
+		}
+		if ical.End() != newEnd {
+			t.Error("End not updated correctly")
+		}
+
+		if ical.getTimeField("DTSTAMP").Sub(time.Now()) > 5*time.Second {
+			t.Error("Timestamp doesn't seem to be updated")
+		}
+	})
 }
 
 const icsWithTZ = `BEGIN:VCALENDAR