Convert RDate/ExDate properties <-> Android RDATE/EXDATE strings more precisely (+ tests)

app/src/androidTest/java/at/bitfire/davdroid/DateUtilsTest.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid;
+
+import junit.framework.TestCase;
+
+import net.fortuna.ical4j.model.Date;
+import net.fortuna.ical4j.model.DateList;
+import net.fortuna.ical4j.model.TimeZone;
+import net.fortuna.ical4j.model.TimeZoneRegistry;
+import net.fortuna.ical4j.model.TimeZoneRegistryFactory;
+import net.fortuna.ical4j.model.parameter.Value;
+import net.fortuna.ical4j.model.property.DateListProperty;
+import net.fortuna.ical4j.model.property.ExDate;
+import net.fortuna.ical4j.model.property.RDate;
+
+import java.text.ParseException;
+import java.util.ArrayList;
+import java.util.List;
+
+public class DateUtilsTest extends TestCase {
+	private static final String tzIdVienna = "Europe/Vienna";
+
+	public void testRecurrenceSetsToAndroidString() throws ParseException {
+		// one entry without time zone (implicitly UTC)
+		final List<RDate> list = new ArrayList<>(2);
+		list.add(new RDate(new DateList("20150101T103010Z,20150102T103020Z", Value.DATE_TIME)));
+		assertEquals("20150101T103010Z,20150102T103020Z", DateUtils.recurrenceSetsToAndroidString(list, false));
+
+		// two entries (previous one + this), both with time zone Vienna
+		list.add(new RDate(new DateList("20150103T113030,20150704T123040", Value.DATE_TIME)));
+		final TimeZone tz = DateUtils.tzRegistry.getTimeZone(tzIdVienna);
+		for (RDate rdate : list)
+			rdate.setTimeZone(tz);
+		assertEquals("20150101T103010Z,20150102T103020Z,20150103T103030Z,20150704T103040Z", DateUtils.recurrenceSetsToAndroidString(list, false));
+
+		// DATEs (without time) have to be converted to <date>T000000Z for Android
+		list.clear();
+		list.add(new RDate(new DateList("20150101,20150702", Value.DATE)));
+		assertEquals("20150101T000000Z,20150702T000000Z", DateUtils.recurrenceSetsToAndroidString(list, true));
+
+		// DATE-TIME (floating time or UTC) recurrences for all-day events have to converted to <date>T000000Z for Android
+		list.clear();
+		list.add(new RDate(new DateList("20150101T000000,20150702T000000Z", Value.DATE_TIME)));
+		assertEquals("20150101T000000Z,20150702T000000Z", DateUtils.recurrenceSetsToAndroidString(list, true));
+	}
+
+	public void testAndroidStringToRecurrenceSets() throws ParseException {
+		// list of UTC times
+		ExDate exDate = (ExDate)DateUtils.androidStringToRecurrenceSet("20150101T103010Z,20150702T103020Z", ExDate.class, false);
+		DateList exDates = exDate.getDates();
+		assertEquals(Value.DATE_TIME, exDates.getType());
+		assertTrue(exDates.isUtc());
+		assertEquals(2, exDates.size());
+		assertEquals(1420108210000L, exDates.get(0).getTime());
+		assertEquals(1435833020000L, exDates.get(1).getTime());
+
+		// list of time zone times
+		exDate = (ExDate)DateUtils.androidStringToRecurrenceSet(tzIdVienna + ";20150101T103010,20150702T103020", ExDate.class, false);
+		exDates = exDate.getDates();
+		assertEquals(Value.DATE_TIME, exDates.getType());
+		assertEquals(DateUtils.tzRegistry.getTimeZone(tzIdVienna), exDates.getTimeZone());
+		assertEquals(2, exDates.size());
+		assertEquals(1420104610000L, exDates.get(0).getTime());
+		assertEquals(1435825820000L, exDates.get(1).getTime());
+
+		// list of dates
+		exDate = (ExDate)DateUtils.androidStringToRecurrenceSet("20150101T103010Z,20150702T103020Z", ExDate.class, true);
+		exDates = exDate.getDates();
+		assertEquals(Value.DATE, exDates.getType());
+		assertEquals(2, exDates.size());
+		assertEquals("20150101", exDates.get(0).toString());
+		assertEquals("20150702", exDates.get(1).toString());
+	}
+
+}

app/src/androidTest/java/at/bitfire/davdroid/resource/LocalCalendarTest.java

@@ -30,17 +30,22 @@ import net.fortuna.ical4j.model.Dur;
 import net.fortuna.ical4j.model.TimeZone;
 import net.fortuna.ical4j.model.TimeZoneRegistry;
 import net.fortuna.ical4j.model.TimeZoneRegistryFactory;
+import net.fortuna.ical4j.model.ValidationException;
 import net.fortuna.ical4j.model.component.VAlarm;
 import net.fortuna.ical4j.model.parameter.Value;
+import net.fortuna.ical4j.model.property.DateListProperty;
 import net.fortuna.ical4j.model.property.DtEnd;
 import net.fortuna.ical4j.model.property.DtStart;
+import net.fortuna.ical4j.model.property.ExDate;
 import net.fortuna.ical4j.model.property.RDate;
+import net.fortuna.ical4j.util.Dates;
 
 import java.text.ParseException;
 import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.List;
 
+import at.bitfire.davdroid.DateUtils;
 import lombok.Cleanup;
 
 public class LocalCalendarTest extends InstrumentationTestCase {
@@ -133,8 +138,7 @@ public class LocalCalendarTest extends InstrumentationTestCase {
 	public void testBuildEntry() throws LocalStorageException, ParseException {
 		final String vcardName = "testBuildEntry";
 
-		TimeZoneRegistry tzRegistry = TimeZoneRegistryFactory.getInstance().createRegistry();
+		final TimeZone tzVienna = DateUtils.tzRegistry.getTimeZone("Europe/Vienna");
-		TimeZone tzVienna = tzRegistry.getTimeZone("Europe/Vienna");
 		assertNotNull(tzVienna);
 
 		// build and write event to calendar provider
@@ -231,23 +235,4 @@ public class LocalCalendarTest extends InstrumentationTestCase {
 		}
 	}
 
-	public void testRecurrenceSetsToAndroidString() throws ParseException {
-		final String tzId = "Europe/Vienna";
-
-		// one entry without time zone
-		final List<RDate> list = new ArrayList<>(2);
-		list.add(new RDate(new DateList("20150101T103000,20150102T103000", Value.DATE_TIME)));
-		assertEquals("20150101T103000,20150102T103000", LocalCalendar.recurrenceSetsToAndroidString(list));
-
-		// two entries with time zone
-		list.add(new RDate(new DateList("20150103T103000,20150104T103000", Value.DATE_TIME)));
-
-		final TimeZoneRegistry tzRegistry = TimeZoneRegistryFactory.getInstance().createRegistry();
-		final TimeZone tz = tzRegistry.getTimeZone(tzId);
-		for (RDate rdate : list)
-			rdate.setTimeZone(tz);
-
-		assertEquals(tzId + ";20150101T103000,20150102T103000,20150103T103000,20150104T103000", LocalCalendar.recurrenceSetsToAndroidString(list));
-	}
-
 }

app/src/main/java/at/bitfire/davdroid/DateUtils.java

@@ -11,19 +11,43 @@ package at.bitfire.davdroid;
 import android.text.format.Time;
 import android.util.Log;
 
+import net.fortuna.ical4j.model.Date;
+import net.fortuna.ical4j.model.DateList;
+import net.fortuna.ical4j.model.DateTime;
 import net.fortuna.ical4j.model.DefaultTimeZoneRegistryFactory;
 import net.fortuna.ical4j.model.TimeZone;
 import net.fortuna.ical4j.model.TimeZoneRegistry;
+import net.fortuna.ical4j.model.TimeZoneRegistryFactory;
+import net.fortuna.ical4j.model.parameter.Value;
+import net.fortuna.ical4j.model.property.DateListProperty;
+import net.fortuna.ical4j.model.property.ExDate;
+import net.fortuna.ical4j.model.property.RDate;
+import net.fortuna.ical4j.util.TimeZones;
 
 import org.apache.commons.lang3.StringUtils;
 
+import java.lang.reflect.InvocationTargetException;
+import java.text.DateFormat;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.GregorianCalendar;
+import java.util.LinkedList;
+import java.util.List;
 import java.util.SimpleTimeZone;
+import java.util.StringTokenizer;
 
 public class DateUtils {
     private final static String TAG = "davdroid.DateUtils";
 
-	private final static TimeZoneRegistry tzRegistry = new DefaultTimeZoneRegistryFactory().createRegistry();
+	public final static TimeZoneRegistry tzRegistry = TimeZoneRegistryFactory.getInstance().createRegistry();
 
+	static {
+		// disable automatic time-zone updates (causes unwanted network traffic)
+		System.setProperty("net.fortuna.ical4j.timezone.update.enabled", "false");
+	}
+
+
+	// time zones
 
     public static String findAndroidTimezoneID(String tzID) {
         String localTZ = null;
@@ -56,8 +80,95 @@ public class DateUtils {
         return localTZ;
     }
 
-	public static TimeZone getTimeZone(String tzID) {
+
-		return tzRegistry.getTimeZone(tzID);
+	// recurrence sets
+
+	/**
+	 * Concatenates, if necessary, multiple RDATE/EXDATE lists and converts them to
+	 * a formatted string which Android calendar provider can process.
+	 * Android expects this format: "[TZID;]date1,date2,date3" where date is "yyyymmddThhmmss" (when
+	 * TZID is given) or "yyyymmddThhmmssZ". We don't use the TZID format here because then we're limited
+	 * to one time-zone, while an iCalendar may contain multiple EXDATE/RDATE lines with different time zones.
+	 * @param dates		one more more lists of RDATE or EXDATE
+	 * @param allDay    indicates whether the event is an all-day event or not
+	 * @return			formatted string for Android calendar provider:
+	 *                  - in case of all-day events, all dates/times are returned as yyyymmddT000000Z
+	 *                  - in case of timed events, all dates/times are returned as UTC time: yyyymmddThhmmssZ
+	 */
+	public static String recurrenceSetsToAndroidString(List<? extends DateListProperty> dates, boolean allDay) throws ParseException {
+		List<String> strDates = new LinkedList<>();
+
+		/*        rdate/exdate: DATE                                DATE_TIME
+		    all-day             store as ...T000000Z                cut off time and store as ...T000000Z
+		    event with time     (ignored)                           store as ...ThhmmssZ
+		*/
+		final DateFormat dateFormatUtcMidnight = new SimpleDateFormat("yyyyMMdd'T'000000'Z'");
+
+		for (DateListProperty dateListProp : dates) {
+			final Value type = dateListProp.getDates().getType();
+
+			if (Value.DATE_TIME.equals(type)) {         // DATE-TIME values will be stored in UTC format for Android
+				if (allDay) {
+					DateList dateList = dateListProp.getDates();
+					for (Date date : dateList)
+						strDates.add(dateFormatUtcMidnight.format(date));
+				} else {
+					dateListProp.setUtc(true);
+					strDates.add(dateListProp.getValue());
+				}
+
+			} else if (Value.DATE.equals(type))       // DATE values have to be converted to DATE-TIME <date>T000000Z for Android
+				for (Date date : dateListProp.getDates())
+					strDates.add(dateFormatUtcMidnight.format(date));
+		}
+		return StringUtils.join(strDates, ",");
+	}
+
+	/**
+	 * Takes a formatted string as provided by the Android calendar provider and returns a DateListProperty
+	 * constructed from these values.
+	 * @param dbStr     formatted string from Android calendar provider (RDATE/EXDATE field)
+	 *                  expected format: "[TZID;]date1,date2,date3" where date is "yyyymmddThhmmss[Z]"
+	 * @param type      subclass of DateListProperty, e.g. RDate or ExDate
+	 * @param allDay    true: list will contain DATE values; false: list will contain DATE_TIME values
+	 * @return          instance of "type" containing the parsed dates/times from the string
+	 */
+	public static DateListProperty androidStringToRecurrenceSet(String dbStr, Class<? extends DateListProperty> type, boolean allDay) throws ParseException {
+		// 1. split string into time zone and actual dates
+		TimeZone timeZone;
+		String datesStr;
+		final int limiter = dbStr.indexOf(';');
+		if (limiter != -1) {    // TZID given
+			timeZone = DateUtils.tzRegistry.getTimeZone(dbStr.substring(0, limiter));
+			datesStr = dbStr.substring(limiter + 1);
+		} else {
+			timeZone = null;
+			datesStr = dbStr;
+		}
+
+		// 2. process date string and generate list of DATEs or DATE-TIMEs
+		DateList dateList;
+		if (allDay) {
+			dateList = new DateList(Value.DATE);
+			for (String s: StringUtils.split(datesStr, ','))
+				dateList.add(new Date(new DateTime(s)));
+		} else {
+			dateList = new DateList(datesStr, Value.DATE_TIME, timeZone);
+			if (timeZone == null)
+				dateList.setUtc(true);
+		}
+
+		// 3. generate requested DateListProperty (RDate/ExDate) from list of DATEs or DATE-TIMEs
+		DateListProperty list;
+		try {
+			list = (DateListProperty)type.getDeclaredConstructor(new Class[] { DateList.class } ).newInstance(dateList);
+			if (dateList.getTimeZone() != null)
+				list.setTimeZone(dateList.getTimeZone());
+		} catch (Exception e) {
+			throw new ParseException("Couldn't create date/time list by reflection", -1);
+		}
+
+		return list;
 	}
 
 }

app/src/main/java/at/bitfire/davdroid/resource/Event.java

@@ -321,7 +321,7 @@ public class Event extends iCalendar {
 			dtStart = new DtStart(new Date(tsStart));
 		} else {
 			DateTime start = new DateTime(tsStart);
-			start.setTimeZone(tzRegistry.getTimeZone(tzID));
+			start.setTimeZone(DateUtils.tzRegistry.getTimeZone(tzID));
 			dtStart = new DtStart(start);
 		}
 	}
@@ -340,7 +340,7 @@ public class Event extends iCalendar {
 			dtEnd = new DtEnd(new Date(tsEnd));
 		} else {
 			DateTime end = new DateTime(tsEnd);
-			end.setTimeZone(tzRegistry.getTimeZone(tzID));
+			end.setTimeZone(DateUtils.tzRegistry.getTimeZone(tzID));
 			dtEnd = new DtEnd(end);
 		}
 	}

app/src/main/java/at/bitfire/davdroid/resource/LocalCalendar.java

@@ -41,6 +41,7 @@ import net.fortuna.ical4j.model.parameter.Cn;
 import net.fortuna.ical4j.model.parameter.CuType;
 import net.fortuna.ical4j.model.parameter.PartStat;
 import net.fortuna.ical4j.model.parameter.Role;
+import net.fortuna.ical4j.model.parameter.Value;
 import net.fortuna.ical4j.model.property.Action;
 import net.fortuna.ical4j.model.property.Attendee;
 import net.fortuna.ical4j.model.property.DateListProperty;
@@ -61,6 +62,7 @@ import java.net.URISyntaxException;
 import java.text.ParseException;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.StringTokenizer;
 
 import at.bitfire.davdroid.DAVUtils;
 import at.bitfire.davdroid.DateUtils;
@@ -239,7 +241,7 @@ public class LocalCalendar extends LocalCollection<Event> {
 				" AND " + Events.ORIGINAL_SYNC_ID + " NOT IN (" + StringUtils.join(sqlFileNames, ",") + ")";    // retain by remote file name
 		pendingOperations.add(ContentProviderOperation
 				.newDelete(entriesURI())
-				.withSelection(where, new String[]{ String.valueOf(id) })
+				.withSelection(where, new String[]{String.valueOf(id)})
 				.withYieldAllowed(true)
 				.build()
 		);
@@ -349,8 +351,7 @@ public class LocalCalendar extends LocalCollection<Event> {
 
 			String strRDate = values.getAsString(Events.RDATE);
 			if (!StringUtils.isEmpty(strRDate)) {
-				RDate rDate = new RDate();
+				RDate rDate = (RDate)DateUtils.androidStringToRecurrenceSet(strRDate, RDate.class, allDay);
-				rDate.setValue(strRDate);
 				e.getRdates().add(rDate);
 			}
 
@@ -363,9 +364,7 @@ public class LocalCalendar extends LocalCollection<Event> {
 
 			String strExDate = values.getAsString(Events.EXDATE);
 			if (!StringUtils.isEmpty(strExDate)) {
-				// always empty, see https://code.google.com/p/android/issues/detail?id=172411
+				ExDate exDate = (ExDate)DateUtils.androidStringToRecurrenceSet(strExDate, ExDate.class, allDay);
-				ExDate exDate = new ExDate();
-				exDate.setValue(strExDate);
 				e.getExdates().add(exDate);
 			}
 		} catch (ParseException ex) {
@@ -540,12 +539,20 @@ public class LocalCalendar extends LocalCollection<Event> {
 		}
 		if (!event.getRdates().isEmpty()) {
 			recurring = true;
-			builder.withValue(Events.RDATE, recurrenceSetsToAndroidString(event.getRdates()));
+			try {
+				builder.withValue(Events.RDATE, DateUtils.recurrenceSetsToAndroidString(event.getRdates(), event.isAllDay()));
+			} catch (ParseException e) {
+				Log.e(TAG, "Couldn't parse RDate(s)", e);
+			}
 		}
 		if (event.getExrule() != null)
 			 builder.withValue(Events.EXRULE, event.getExrule().getValue());
 		if (!event.getExdates().isEmpty())
-			builder.withValue(Events.EXDATE, recurrenceSetsToAndroidString(event.getExdates()));
+			try {
+				builder.withValue(Events.EXDATE, DateUtils.recurrenceSetsToAndroidString(event.getExdates(), event.isAllDay()));
+			} catch (ParseException e) {
+				Log.e(TAG, "Couldn't parse ExDate(s)", e);
+			}
 
 		// set either DTEND for single-time events or DURATION for recurring events
 		// because that's the way Android likes it (see docs)
@@ -613,10 +620,10 @@ public class LocalCalendar extends LocalCollection<Event> {
 				.withSelection(Events.ORIGINAL_ID + "=?", new String[] { String.valueOf(event.getLocalID())}).build());
 		// delete attendees
 		pendingOperations.add(ContentProviderOperation.newDelete(syncAdapterURI(Attendees.CONTENT_URI))
-				.withSelection(Attendees.EVENT_ID + "=?", new String[] { String.valueOf(event.getLocalID()) }).build());
+				.withSelection(Attendees.EVENT_ID + "=?", new String[]{String.valueOf(event.getLocalID())}).build());
 		// delete reminders
 		pendingOperations.add(ContentProviderOperation.newDelete(syncAdapterURI(Reminders.CONTENT_URI))
-				.withSelection(Reminders.EVENT_ID + "=?", new String[] { String.valueOf(event.getLocalID()) }).build());
+				.withSelection(Reminders.EVENT_ID + "=?", new String[]{String.valueOf(event.getLocalID())}).build());
 	}
 
 
@@ -731,34 +738,4 @@ public class LocalCalendar extends LocalCollection<Event> {
 		return calendarsURI(account);
 	}
 
-	/**
-	 * Concatenates, if necessary, multiple RDATE/EXDATE lists and prepares
-	 * a formatted string as expected by Android calendar provider
-	 * @param dates		one more more lists of RDATE or EXDATE
-	 * @return			formatted string for Android calendar provider
-	 */
-	static String recurrenceSetsToAndroidString(List<? extends DateListProperty> dates) {
-		String tzID = null;
-		List<String> strDates = new LinkedList<>();
-
-		for (DateListProperty dateList : dates) {
-			if (dateList.getTimeZone() != null) {
-				String thisTzID = DateUtils.findAndroidTimezoneID(dateList.getTimeZone().getID());
-				if (tzID == null)
-					tzID = thisTzID;
-				else if (!tzID.equals(thisTzID))
-					Log.w(TAG, "Multiple EXDATEs/RDATEs with different time zones not supported by Android, using " + tzID + " for all dates");
-			}
-			strDates.add(dateList.getValue());
-		}
-
-		// Android expects this format: "[TZID;]date1,date2,date3"
-		String dateStr = "";
-		if (tzID != null)
-			dateStr += tzID + ";";
-		dateStr += StringUtils.join(strDates, ",");
-
-		return dateStr;
-	}
-
 }

app/src/main/java/at/bitfire/davdroid/resource/LocalTaskList.java

@@ -204,7 +204,7 @@ public class LocalTaskList extends LocalCollection<Task> {
 
 				TimeZone tz = null;
 				if (!cursor.isNull(8))
-					tz = DateUtils.getTimeZone(cursor.getString(8));
+					tz = DateUtils.tzRegistry.getTimeZone(cursor.getString(8));
 
 				if (!cursor.isNull(9) && !cursor.isNull(10)) {
 					long ts = cursor.getLong(9);
@@ -327,7 +327,7 @@ public class LocalTaskList extends LocalCollection<Task> {
 
 		// TZ *must* be provided when DTSTART or DUE is set
 		if ((task.getDtStart() != null || task.getDue() != null) && tz == null)
-			tz = DateUtils.getTimeZone(TimeZones.GMT_ID);
+			tz = DateUtils.tzRegistry.getTimeZone(TimeZones.GMT_ID);
 		if (tz != null)
 			builder.withValue(TaskContract.Tasks.TZ, DateUtils.findAndroidTimezoneID(tz.getID()));
 

app/src/main/java/at/bitfire/davdroid/resource/iCalendar.java

@@ -40,13 +40,8 @@ public abstract class iCalendar extends Resource {
 		CompatibilityHints.setHintEnabled(CompatibilityHints.KEY_RELAXED_UNFOLDING, true);
 		CompatibilityHints.setHintEnabled(CompatibilityHints.KEY_RELAXED_PARSING, true);
 		CompatibilityHints.setHintEnabled(CompatibilityHints.KEY_OUTLOOK_COMPATIBILITY, true);
-
-		// disable automatic time-zone updates (causes unwanted network traffic)
-		System.setProperty("net.fortuna.ical4j.timezone.update.enabled", "false");
 	}
 
-	static protected final TimeZoneRegistry tzRegistry = new DefaultTimeZoneRegistryFactory().createRegistry();
-
 
 	public iCalendar(long localID, String name, String ETag) {
 		super(localID, name, ETag);
@@ -103,7 +98,7 @@ public abstract class iCalendar extends Resource {
 			return;
 
 		String localTZ = DateUtils.findAndroidTimezoneID(tzID);
-		date.setTimeZone(tzRegistry.getTimeZone(localTZ));
+		date.setTimeZone(DateUtils.tzRegistry.getTimeZone(localTZ));
 	}
 
 	public static String TimezoneDefToTzId(String timezoneDef) throws IllegalArgumentException {