Reaplce EventWriter by ICalendarWriter

Author: rfc2822

lib/src/main/kotlin/at/bitfire/ical4android/EventWriter.kt

@@ -13,6 +13,7 @@ import net.fortuna.ical4j.model.ComponentList
 import net.fortuna.ical4j.model.DateTime
 import net.fortuna.ical4j.model.TimeZone
 import net.fortuna.ical4j.model.component.CalendarComponent
+import net.fortuna.ical4j.model.property.DateProperty
 import net.fortuna.ical4j.model.property.ProdId
 import net.fortuna.ical4j.model.property.Version
 import java.io.Writer
@@ -56,12 +57,13 @@ class ICalendarWriter(
         val usedTimeZones = mutableSetOf<TimeZone>()
         var firstTs: Long? = null
         for (component in components)
-            for (dateProperty in component.properties.filterIsInstance<DateTime>()) {
-                usedTimeZones += dateProperty.timeZone
+            for (dateProperty in component.properties.filterIsInstance<DateProperty>()) {
+                if (dateProperty.timeZone != null)
+                    usedTimeZones += dateProperty.timeZone
                 firstTs = if (firstTs == null)
-                    dateProperty.time
+                    dateProperty.date.time
                 else
-                    min(firstTs, dateProperty.time)
+                    min(firstTs, dateProperty.date.time)
             }
         return TimeZoneInfo(
             usedTimeZones = usedTimeZones,

lib/src/main/kotlin/at/bitfire/synctools/icalendar/ICalendarWriter.kt

@@ -0,0 +1,72 @@
+/*
+ * This file is part of bitfireAT/synctools which is released under GPLv3.
+ * Copyright © All Contributors. See the LICENSE and AUTHOR files in the root directory for details.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package at.bitfire.synctools.icalendar
+
+import net.fortuna.ical4j.model.ComponentList
+import net.fortuna.ical4j.model.TimeZoneRegistryFactory
+import net.fortuna.ical4j.model.component.VAlarm
+import net.fortuna.ical4j.model.component.VEvent
+import net.fortuna.ical4j.model.property.Attendee
+import net.fortuna.ical4j.model.property.DtEnd
+import net.fortuna.ical4j.model.property.DtStart
+import net.fortuna.ical4j.model.property.Uid
+import net.fortuna.ical4j.util.TimeZones
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import java.io.StringWriter
+import java.time.Duration
+
+class ICalendarWriterTest {
+
+    private val tzRegistry = TimeZoneRegistryFactory.getInstance().createRegistry()
+    private val tzBerlin = tzRegistry.getTimeZone("Europe/Berlin")!!
+    private val tzUTC = tzRegistry.getTimeZone(TimeZones.UTC_ID)!!
+
+    private val writer = ICalendarWriter(prodId = javaClass.name)
+
+    @Test
+    fun testGenerateEtcUTC() {
+        val e = VEvent().apply {
+            properties += Uid("etc-utc-test@example.com")
+            properties += DtStart("20200926T080000", tzUTC)
+            properties += DtEnd("20200926T100000", tzUTC)
+            properties += Attendee("mailto:test@example.com")
+            components += VAlarm(Duration.ofMinutes(-30))
+        }
+        val ical = StringWriter()
+        writer.write(ComponentList(listOf(e)), ical)
+
+        assertTrue(
+            "BEGIN:VTIMEZONE.+BEGIN:STANDARD.+END:STANDARD.+END:VTIMEZONE"
+                .toRegex(RegexOption.DOT_MATCHES_ALL)
+                .containsMatchIn(ical.toString())
+        )
+    }
+
+    @Test
+    fun testWrite() {
+        val e = VEvent().apply {
+            properties += Uid("SAMPLEUID")
+            properties += DtStart("20190101T100000", tzBerlin)
+            components += VAlarm(Duration.ofHours(-1))
+        }
+
+        val iCal = StringWriter()
+        writer.write(ComponentList(listOf(e)), iCal)
+        val raw = iCal.toString()
+
+        assertTrue(raw.contains("PRODID:${javaClass.name}"))
+        assertTrue(raw.contains("UID:SAMPLEUID"))
+        assertTrue(raw.contains("DTSTART;TZID=Europe/Berlin:20190101T100000"))
+        assertTrue(raw.contains("DTSTAMP:"))
+        assertTrue(raw.contains("BEGIN:VALARM\r\n" +
+                "TRIGGER:-PT1H\r\n" +
+                "END:VALARM\r\n"))
+        assertTrue(raw.contains("BEGIN:VTIMEZONE"))
+    }
+
+}