[evolution-mapi] Bug #629057 - Some events created in evolution are missing in OWA

[Milan Crha <mcrha src gnome org>]

commit e2d52ebb485d0c3e38c10a3ba4f280c0342ce52b
Author: Sean Finney <seanius seanius net>
Date:   Wed May 4 15:36:45 2011 +0200

    Bug #629057 - Some events created in evolution are missing in OWA
    
    For recurring instances, an extra MAPI named property PidLidTimeZone
    is required for the events to appear in OWA.  The value of this property
    is an index into a rather arbitrarily defined table of timezone DST/SDT
    transition rules.
    
    Since we can not guarantee that the table will match 100% to the current
    or future timezone transition rules, use a best effort heuristic to find
    the closest matching rule;  for all table entries with the same UTC offset
    as the current timezone, test dates before and after the transition
    rules and take the entry which matches closest to what is expected.

 src/libexchangemapi/exchange-mapi-cal-tz-utils.c |  195 ++++++++++++++++++++++
 src/libexchangemapi/exchange-mapi-cal-tz-utils.h |    3 +
 src/libexchangemapi/exchange-mapi-cal-utils.c    |   18 ++-
 3 files changed, 215 insertions(+), 1 deletions(-)
---
diff --git a/src/libexchangemapi/exchange-mapi-cal-tz-utils.c b/src/libexchangemapi/exchange-mapi-cal-tz-utils.c
index 893edc0..9e3ed84 100644
--- a/src/libexchangemapi/exchange-mapi-cal-tz-utils.c
+++ b/src/libexchangemapi/exchange-mapi-cal-tz-utils.c
@@ -567,3 +567,198 @@ exchange_mapi_cal_util_bin_to_mapi_tz (GByteArray *ba)
 
 	return buf;
 }
+
+/* Corresponds to the first table in OXOCAL 2.2.5.6.
+   - has_dst is signifies whether the SDT/DST entries are relevant or "N/A"
+   - utc_offset is in minutes east of UTC
+ */
+struct pltz_mapentry {
+	gboolean has_dst;
+	int utc_offset;
+	int standard_wMonth;
+	int standard_wDayOfWeek;
+	int standard_wDay;
+	int standard_wHour;
+	int daylight_wMonth;
+	int daylight_wDayOfWeek;
+	int daylight_wDay;
+	int daylight_wHour;
+};
+
+/* Table contents, current as of [MS-OXOCAL] - v20110315 */
+static const struct pltz_mapentry pltz_table[] = {
+	{ FALSE,  720,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,     0, 10, 0, 5, 2,   3, 0, 5, 1 },
+	{ TRUE,    60,  9, 0, 5, 2,   3, 0, 5, 1 },
+	{ TRUE,    60, 10, 0, 5, 3,   3, 0, 5, 2 },
+	{ TRUE,    60, 10, 0, 5, 3,   3, 0, 5, 2 },
+	{ TRUE,   120,  9, 0, 5, 1,   3, 0, 5, 0 },
+	{ TRUE,    60,  9, 0, 5, 1,   3, 0, 5, 0 },
+	{ TRUE,   120, 10, 0, 5, 4,   3, 0, 5, 3 },
+	{ TRUE,  -180,  2, 0, 2, 2,  10, 0, 3, 2 },
+	{ TRUE,  -240, 11, 0, 1, 2,   3, 0, 2, 2 },
+	{ TRUE,  -300, 11, 0, 1, 2,   3, 0, 2, 2 },
+	{ TRUE,  -360, 11, 0, 1, 2,   3, 0, 2, 2 },
+	{ TRUE,  -420, 11, 0, 1, 2,   3, 0, 2, 2 },
+	{ TRUE,  -480, 11, 0, 1, 2,   3, 0, 2, 2 },
+	{ TRUE,  -540, 11, 0, 1, 2,   3, 0, 2, 2 },
+	{ FALSE, -600,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -660,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   720,  4, 0, 1, 3,   9, 0, 5, 2 },
+	{ TRUE,   600,  3, 0, 5, 3,  10, 0, 5, 2 },
+	{ TRUE,   570,  3, 0, 5, 3,  10, 0, 5, 2 },
+	{ FALSE,  540,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  480,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  420,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  330,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  240,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   210,  9, 2, 4, 2,   3, 0, 1, 2 },
+	{ FALSE,  180,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   120,  9, 0, 3, 2,   3, 5, 5, 2 },
+	{ TRUE,  -210, 11, 0, 1, 0,   3, 0, 2, 0 },
+	{ TRUE,   -60, 10, 0, 5, 1,   3, 0, 5, 0 },
+	{ TRUE,  -120, 10, 0, 5, 1,   3, 0, 5, 0 },
+	{ FALSE,    0,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -180,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -240,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -300,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -300,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -360,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,  -360, 10, 0, 5, 2,   4, 0, 1, 2 },
+	{ FALSE, -420,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE, -720,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  720,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  660,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   600,  3, 0, 5, 2,  10, 0, 1, 2 },
+	{ FALSE,  600,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  570,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   480,  9, 0, 2, 2,   4, 0, 2, 2 },
+	{ FALSE,  360,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  300,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ FALSE,  270,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   120,  9, 4, 5, 2,   5, 5, 1, 2 },
+	{ FALSE,  120,  0, 0, 0, 0,   0, 0, 0, 0 },
+	{ TRUE,   180, 10, 0, 5, 1,   3, 0, 5, 0 },
+	{ TRUE,   600,  3, 0, 5, 2,   8, 0, 5, 2 },
+	{ TRUE,   600,  4, 0, 1, 3,  10, 0, 5, 2 },
+	{ TRUE,   570,  4, 0, 1, 3,  10, 0, 5, 2 },
+	{ TRUE,   600,  4, 0, 1, 3,  10, 0, 1, 2 },
+	{ TRUE,  -240,  3, 6, 2, 23, 10, 6, 2, 23 },
+	{ TRUE,   480,  3, 0, 5, 3,  10, 0, 5, 2 },
+	{ TRUE,  -420, 10, 0, 5, 2,   4, 0, 1, 2 },
+	{ TRUE,  -480, 10, 0, 5, 2,   4, 0, 1, 2 }
+};
+
+/* Return the ordinal-th wday day in month as a time_t in the local time.
+	@year: year in decimal form
+	@month: month (1 == Jan)
+	@wday: weekday (0 == Sunday)
+	@ordinal: nth occurence of wday, or last occurrence if out of bounds
+ */
+static time_t
+nth_day_of_month (int year, int month, int wday, int ordinal)
+{
+	struct tm stm = {0};
+	time_t ts;
+
+	/* first day of month */
+	stm.tm_year = year - 1900;
+	stm.tm_mon = month - 1;
+	stm.tm_mday = 1;
+
+	ts = mktime (&stm);
+	/* go to first instance of wday in month */
+	ts += (60 * 60 * 24) * (wday - stm.tm_wday + 7 * (wday < stm.tm_wday));
+	/* go to the n weeks in the future */
+	ts += (60 * 60 * 24 * 7) * (ordinal - 1);
+	localtime_r (&ts, &stm);
+	/* the MS spec says that the 5th such weekday of the month always
+	   refers to the last such day, even if it is the 4th.  So, check to
+       see if we're in the same month, and if not, rewind a week. */
+	if (stm.tm_mon != month - 1)
+		ts -= (60 * 60 * 24 * 7);
+
+	return ts;
+}
+
+/* return the most-correct PidLidTimeZone value w.r.t. OXOCAL 2.2.5.6. */
+int
+exchange_mapi_cal_util_mapi_tz_pidlidtimezone (icaltimezone *ictz)
+{
+	gboolean tz_dst_now = FALSE, tz_has_dst = FALSE;
+	int i, utc_offset = 0, best_index = 0, best_score = -1;
+	const char *tznames;
+	icaltimetype tt;
+
+	if (ictz == NULL)
+		return 0;
+
+	/* Simple hack to determine if our TZ has DST */
+	tznames = icaltimezone_get_tznames (ictz);
+	if (tznames && strchr (tznames, '/'))
+		tz_has_dst = TRUE;
+
+	/* Calculate minutes east of UTC, what MS uses in this spec */
+	tt = icaltime_current_time_with_zone (ictz);
+	utc_offset = icaltimezone_get_utc_offset (ictz, &tt, &tz_dst_now) / 60;
+	if (tz_dst_now)
+		utc_offset -= 60;
+
+	/* Find the PidLidTimeZone entry that matches the most closely to
+	   the SDT/DST rules for the given timezone */
+	for (i = 0; i < sizeof (pltz_table) / sizeof (struct pltz_mapentry); ++i) {
+		const struct pltz_mapentry *pme = &pltz_table[i];
+		time_t pre_sdt, sdt, post_sdt, pre_dst, dst, post_dst;
+		struct tm pre_stm, stm, post_stm;
+		int score = 0;
+
+		if (pme->utc_offset == utc_offset && tz_has_dst == pme->has_dst)
+			score = 1;
+
+		if (score && tz_has_dst) {
+			sdt = nth_day_of_month (tt.year, pme->standard_wMonth,
+			                        pme->standard_wDayOfWeek,
+			                        pme->standard_wDay);
+			/* add the transition hour and a second */
+			sdt += (pme->standard_wHour * 60 * 60) + 1;
+			pre_sdt = sdt - 2 * 60 * 60;
+			post_sdt = sdt + 2 * 60 * 60;
+
+			dst = nth_day_of_month (tt.year, pme->daylight_wMonth,
+			                        pme->daylight_wDayOfWeek,
+			                        pme->daylight_wDay);
+			dst += (pme->daylight_wHour * 60 * 60) + 1;
+			pre_dst = dst - 2 * 60 * 60;
+			post_dst = dst + 2 * 60 * 60;
+
+			localtime_r (&sdt, &stm);
+			localtime_r (&pre_sdt, &pre_stm);
+			localtime_r (&post_sdt, &post_stm);
+
+			if (!stm.tm_isdst)
+				score++;
+			if (pre_stm.tm_isdst)
+				score++;
+			if (!post_stm.tm_isdst)
+				score++;
+
+			localtime_r (&dst, &stm);
+			localtime_r (&pre_dst, &pre_stm);
+			localtime_r (&post_dst, &post_stm);
+
+			if (stm.tm_isdst)
+				score++;
+			if (!pre_stm.tm_isdst)
+				score++;
+			if (post_stm.tm_isdst)
+				score++;
+
+			if (score > best_score) {
+				best_score = score;
+				best_index = i;
+			}
+		}
+	}
+
+	return best_index;
+}
diff --git a/src/libexchangemapi/exchange-mapi-cal-tz-utils.h b/src/libexchangemapi/exchange-mapi-cal-tz-utils.h
index b726e17..e73334b 100644
--- a/src/libexchangemapi/exchange-mapi-cal-tz-utils.h
+++ b/src/libexchangemapi/exchange-mapi-cal-tz-utils.h
@@ -48,6 +48,9 @@ exchange_mapi_cal_tz_util_dump (void);
 void
 exchange_mapi_cal_util_mapi_tz_to_bin (const gchar *mapi_tzid, struct Binary_r *sb);
 
+int
+exchange_mapi_cal_util_mapi_tz_pidlidtimezone (icaltimezone *ictz);
+
 gchar *
 exchange_mapi_cal_util_bin_to_mapi_tz (GByteArray *ba);
 
diff --git a/src/libexchangemapi/exchange-mapi-cal-utils.c b/src/libexchangemapi/exchange-mapi-cal-utils.c
index d14d892..a1943b9 100644
--- a/src/libexchangemapi/exchange-mapi-cal-utils.c
+++ b/src/libexchangemapi/exchange-mapi-cal-utils.c
@@ -1223,7 +1223,8 @@ appt_build_name_id (ExchangeMapiConnection *conn, mapi_id_t fid, TALLOC_CTX *mem
 		{ PidLidIsException, 0 },
 		{ PidLidCleanGlobalObjectId, 0 },
 		{ PidLidAppointmentMessageClass, 0 },
-		{ PidLidMeetingType, 0 }
+		{ PidLidMeetingType, 0 },
+		{ PidLidTimeZone, 0 }
 	};
 
 	if (!props)
@@ -1635,6 +1636,21 @@ exchange_mapi_cal_utils_write_props_cb (ExchangeMapiConnection *conn, mapi_id_t
 			set_named_value (PidLidAppointmentTimeZoneDefinitionEndDisplay, &end_tz);
 		}
 
+		/* Recurrences also need to have this rather arbitrary index set
+		   to properly determine SDT/DST and appear in OWA (Bug #629057). */
+		if (e_cal_component_has_recurrences (comp)) {
+			uint64_t pltz;
+			icaltimezone *ictz;
+			const gchar *zone_location = dtstart_tz_location;
+
+			if (!zone_location)
+				zone_location = get_tzid_location ("*default-zone*", cbdata);
+
+			ictz = icaltimezone_get_builtin_timezone (zone_location);
+			pltz = exchange_mapi_cal_util_mapi_tz_pidlidtimezone (ictz);
+			set_named_value (PidLidTimeZone, &pltz);
+		}
+
 		/* Duration */
 		flag32 = icaldurationtype_as_int (icaltime_subtract (dtend, dtstart));
 		flag32 /= MINUTES_IN_HOUR;