From f3b5e3a4aefae1efae0491909b17b12fedfcabf7 Mon Sep 17 00:00:00 2001
From: tibbi <tibor@kaputa.sk>
Date: Sat, 18 Feb 2017 23:08:15 +0100
Subject: [PATCH] improve ics parsing by calculating start + duration if end is
 missing

---
 .../calendar/helpers/IcsParser.kt             | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/app/src/main/kotlin/com/simplemobiletools/calendar/helpers/IcsParser.kt b/app/src/main/kotlin/com/simplemobiletools/calendar/helpers/IcsParser.kt
index 9ac8cab5b..db11db738 100644
--- a/app/src/main/kotlin/com/simplemobiletools/calendar/helpers/IcsParser.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/calendar/helpers/IcsParser.kt
@@ -18,6 +18,7 @@ class IcsParser {
     private val END = "END:VEVENT"
     private val DTSTART = "DTSTART"
     private val DTEND = "DTEND"
+    private val DURATION = "DURATION:"
     private val SUMMARY = "SUMMARY:"
     private val DESCRIPTION = "DESCRIPTION:"
     private val UID = "UID:"
@@ -55,6 +56,9 @@ class IcsParser {
                         curStart = getTimestamp(line.substring(DTSTART.length))
                     } else if (line.startsWith(DTEND)) {
                         curEnd = getTimestamp(line.substring(DTEND.length))
+                    } else if (line.startsWith(DURATION)) {
+                        val duration = line.substring(DURATION.length)
+                        curEnd = calculateEndTime(curStart, duration)
                     } else if (line.startsWith(SUMMARY)) {
                         curTitle = line.substring(SUMMARY.length)
                         curTitle = curTitle.substring(0, Math.min(curTitle.length, 50))
@@ -108,6 +112,24 @@ class IcsParser {
         }
     }
 
+    // P0DT1H0M0S
+    private fun calculateEndTime(curStart: Int, duration: String): Int {
+        val weeks = getDurationValue(duration, "W")
+        val days = getDurationValue(duration, "DT")
+        val hours = getDurationValue(duration, "H")
+        val minutes = getDurationValue(duration, "M")
+        val seconds = getDurationValue(duration, "S")
+
+        val minSecs = 60
+        val hourSecs = minSecs * 60
+        val daySecs = hourSecs * 24
+        val weekSecs = daySecs * 7
+
+        return curStart + seconds + (minutes * minSecs) + (hours * hourSecs) + (days * daySecs) + (weeks * weekSecs)
+    }
+
+    private fun getDurationValue(duration: String, char: String): Int = Regex("[0-9]+(?=$char)").find(duration)?.value?.toInt() ?: 0
+
     private fun parseLongFormat(digitString: String): Int {
         val dateTimeFormat = DateTimeFormat.forPattern("yyyyMMddHHmmss")
         return dateTimeFormat.parseDateTime(digitString).withZoneRetainFields(DateTimeZone.UTC).seconds()