1 files changed, 54 insertions, 0 deletions

diff --git a/icalproxy.go b/icalproxy.go
index 0a3ea36..152eed6 100644
--- a/icalproxy.go
+++ b/icalproxy.go
@@ -5,6 +5,7 @@ import (
         "log"
         "net/http"
         "net/url"
+        "strings"
         "time"
 
         "github.com/emersion/go-ical"
@@ -15,10 +16,16 @@ func main() {
         cfg := loadConfig()
         printConfig(&cfg)
 
+        amsTz, err := time.LoadLocation("Europe/Amsterdam")
+        if err != nil {
+                log.Fatalln("Failed to load time zone", err)
+        }
+
         handler := handler{
                 calURL: url.URL(cfg.CalendarURL.v),
                 ignore: cfg.Ignore,
                 tokens: cfg.UserTokens,
+                amsTz:  amsTz,
         }
 
         mux := http.ServeMux{}
@@ -40,6 +47,7 @@ type handler struct {
         ignore ignoreRules
         tokens map[string]userToken
         calURL url.URL
+        amsTz  *time.Location
 }
 
 func (h handler) makeTokenURL(token string) string {
@@ -72,6 +80,7 @@ func (h handler) handle(w http.ResponseWriter, r *http.Request) {
         }
 
         filter(h.ignore, cal.Component)
+        skewMidnightDeadlines(h.amsTz, cal.Component)
 
         if err = ical.NewEncoder(w).Encode(cal); err != nil {
                 log.Println("Error writing calendar:", err)
@@ -108,6 +117,51 @@ func filter(ignore ignoreRules, c *ical.Component) {
         c.Children = c.Children[:j]
 }
 
+// We often see events which are scheduled for exactly 'end of day', i.e.
+// 23:59:59, with no difference between the start/end time. Unfortunately,
+// these are not shown properly in two open-source Android calendar apps, so we
+// monkey-hack the event to start at 23:30 and add a note to the description :)
+func skewMidnightDeadlines(ams *time.Location, c *ical.Component) {
+        for _, child := range c.Children {
+                if child.Name == ical.CompEvent {
+                        if summary := child.Props.Get(ical.PropSummary); summary != nil &&
+                                strings.HasSuffix(summary.Value, " - Due") {
+
+                                // Modify the start time of the event
+                                startTime, stErr := c.Props.DateTime(ical.PropDateTimeStart, ams)
+                                endTime, etErr := c.Props.DateTime(ical.PropDateTimeEnd, ams)
+                                if stErr != nil || etErr != nil || startTime.IsZero() ||
+                                        endTime.IsZero() || !startTime.Equal(endTime) ||
+                                        startTime.Hour() != 23 || startTime.Minute() != 59 ||
+                                        startTime.Second() != 59 {
+                                        continue
+                                }
+                                newStartTime := time.Date(startTime.Year(), startTime.Month(),
+                                        startTime.Day(), 23, 30, 0, 0, ams)
+                                child.Props.SetDateTime(ical.PropDateTimeStart, newStartTime)
+
+                                // Update the event description to notify about the change
+                                descProp := child.Props.Get(ical.PropDescription)
+                                if descProp == nil {
+                                        descProp = ical.NewProp(ical.PropDescription)
+                                }
+
+                                curText, err := descProp.Text()
+                                if err != nil {
+                                        // forget about editing the text, at least we 'fixed' the
+                                        // event time :)
+                                        continue
+                                }
+                                curText = "+++ ICALPROXY: DEADLINE MOVED FROM 23:59:59 TO" +
+                                        "23:30:00 (Europe/Amsterdam) +++\n\n" + curText
+                                descProp.SetText(curText)
+
+                                child.Props.Set(descProp)
+                        }
+                }
+        }
+}
+
 func userOK(tokens map[string]userToken, id string, token []byte) bool {
         info, ok := tokens[id]
         if !ok {