* Conflict checker loop now stops iterating over existing events when it goes out...
[citadel.git] / citadel / modules / calendar / serv_calendar.c
index 41bedf0268047948043c0daec435e99abed8e7b6..05504d3a7bac99eeb4d977039aa160364649708f 100644 (file)
@@ -19,7 +19,7 @@
 #ifdef HAVE_STRINGS_H
 #include <strings.h>
 #endif
-#include <ical.h>
+#include <libical/ical.h>
 #include <libcitadel.h>
 #include "citadel.h"
 #include "server.h"
@@ -52,8 +52,7 @@ icalcomponent *icalcomponent_new_citadel_vcalendar(void) {
 
        encaps = icalcomponent_new_vcalendar();
        if (encaps == NULL) {
-               CtdlLogPrintf(CTDL_CRIT, "Error at %s:%d - could not allocate component!\n",
-                       __FILE__, __LINE__);
+               CtdlLogPrintf(CTDL_CRIT, "ERROR: could not allocate component!\n");
                return NULL;
        }
 
@@ -87,11 +86,6 @@ icalcomponent *ical_encapsulate_subcomponent(icalcomponent *subcomp) {
        /* Encapsulate the subcomponent inside */
        icalcomponent_add_component(encaps, subcomp);
 
-       /* Convert all timestamps to UTC so we don't have to deal with
-        * stupid VTIMEZONE crap.
-        */
-       ical_dezonify(encaps);
-
        /* Return the object we just created. */
        return(encaps);
 }
@@ -124,7 +118,7 @@ void ical_write_to_cal(struct ctdluser *u, icalcomponent *cal) {
                return;
        }
 
-       ser = icalcomponent_as_ical_string(cal);
+       ser = icalcomponent_as_ical_string_r(cal);
        if (ser == NULL) return;
 
        /* If the caller supplied a user, write to that user's default calendar room */
@@ -162,39 +156,10 @@ void ical_write_to_cal(struct ctdluser *u, icalcomponent *cal) {
        }
 
        /* In either case, now we can free the serialized calendar object */
-//     free(ser);
-}
-
-
-/*
- * Add a calendar object to the user's calendar
- * 
- * ok because it uses ical_write_to_cal()
- */
-void ical_add(icalcomponent *cal, int recursion_level) {
-       icalcomponent *c;
-
-       /*
-        * The VEVENT subcomponent is the one we're interested in saving.
-        */
-       if (icalcomponent_isa(cal) == ICAL_VEVENT_COMPONENT) {
-       
-               ical_write_to_cal(&CC->user, cal);
-
-       }
-
-       /* If the component has subcomponents, recurse through them. */
-       for (c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
-           (c != 0);
-           c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)) {
-               /* Recursively process subcomponent */
-               ical_add(c, recursion_level+1);
-       }
-
+       free(ser);
 }
 
 
-
 /*
  * Send a reply to a meeting invitation.
  *
@@ -315,7 +280,7 @@ void ical_send_a_reply(icalcomponent *request, char *action) {
        }
 
        /* Now generate the reply message and send it out. */
-       serialized_reply = strdup(icalcomponent_as_ical_string(the_reply));
+       serialized_reply = icalcomponent_as_ical_string_r(the_reply);
        icalcomponent_free(the_reply);  /* don't need this anymore */
        if (serialized_reply == NULL) return;
 
@@ -355,7 +320,7 @@ void ical_send_a_reply(icalcomponent *request, char *action) {
  */
 void ical_locate_part(char *name, char *filename, char *partnum, char *disp,
                void *content, char *cbtype, char *cbcharset, size_t length, char *encoding,
-               void *cbuserdata) {
+               char *cbid, void *cbuserdata) {
 
        struct ical_respond_data *ird = NULL;
 
@@ -382,9 +347,6 @@ void ical_locate_part(char *name, char *filename, char *partnum, char *disp,
        }
 
        ird->cal = icalcomponent_new_from_string(content);
-       if (ird->cal != NULL) {
-               ical_dezonify(ird->cal);
-       }
 }
 
 
@@ -435,7 +397,7 @@ void ical_respond(long msgnum, char *partnum, char *action) {
        if (ird.cal != NULL) {
                /* Save this in the user's calendar if necessary */
                if (!strcasecmp(action, "accept")) {
-                       ical_add(ird.cal, 0);
+                       ical_write_to_cal(&CC->user, ird.cal);
                }
 
                /* Send a reply if necessary */
@@ -443,9 +405,9 @@ void ical_respond(long msgnum, char *partnum, char *action) {
                        ical_send_a_reply(ird.cal, action);
                }
 
-               /* Now that we've processed this message, we don't need it
-                * anymore.  So delete it.  (NOTE we don't do this anymore.)
-               CtdlDeleteMessages(CC->room.QRname, &msgnum, 1, "");
+               /* We used to delete the invitation after handling it.
+                * We don't do that anymore, but here is the code that handled it:
+                * CtdlDeleteMessages(CC->room.QRname, &msgnum, 1, "");
                 */
 
                /* Free the memory we allocated and return a response. */
@@ -514,7 +476,7 @@ struct original_event_container {
  */
 void ical_locate_original_event(char *name, char *filename, char *partnum, char *disp,
                void *content, char *cbtype, char *cbcharset, size_t length, char *encoding,
-               void *cbuserdata) {
+               char *cbid, void *cbuserdata) {
 
        struct original_event_container *oec = NULL;
 
@@ -688,7 +650,7 @@ int ical_update_my_calendar_with_reply(icalcomponent *cal) {
        ical_merge_attendee_reply(original_event, cal);
 
        /* Serialize it */
-       serialized_event = strdup(icalcomponent_as_ical_string(original_event));
+       serialized_event = icalcomponent_as_ical_string_r(original_event);
        icalcomponent_free(original_event);     /* Don't need this anymore. */
        if (serialized_event == NULL) return(2);
 
@@ -890,87 +852,236 @@ int ical_ctdl_is_overlap(
 
 
 
+/* 
+ * Phase 6 of "hunt for conflicts"
+ * called by ical_conflicts_phase5()
+ *
+ * Now both the proposed and existing events have been boiled down to start and end times.
+ * Check for overlap and output any conflicts.
+ */
+void ical_conflicts_phase6(struct icaltimetype t1start,
+                       struct icaltimetype t1end,
+                       struct icaltimetype t2start,
+                       struct icaltimetype t2end,
+                       long existing_msgnum,
+                       char *conflict_event_uid,
+                       char *conflict_event_summary,
+                       char *compare_uid)
+{
+
+       /* debugging cruft */
+       time_t tt;
+       tt = icaltime_as_timet(t1start);
+       CtdlLogPrintf(CTDL_DEBUG, "PROPOSED START: %s", ctime(&tt));
+       tt = icaltime_as_timet(t1end);
+       CtdlLogPrintf(CTDL_DEBUG, "  PROPOSED END: %s", ctime(&tt));
+       tt = icaltime_as_timet(t2start);
+       CtdlLogPrintf(CTDL_DEBUG, "EXISTING START: %s", ctime(&tt));
+       tt = icaltime_as_timet(t2end);
+       CtdlLogPrintf(CTDL_DEBUG, "  EXISTING END: %s", ctime(&tt));
+       /* debugging cruft */
+
+       /* compare and output */
+
+       if (ical_ctdl_is_overlap(t1start, t1end, t2start, t2end)) {
+               cprintf("%ld||%s|%s|%d|\n",
+                       existing_msgnum,
+                       conflict_event_uid,
+                       conflict_event_summary,
+                       (       ((strlen(compare_uid)>0)
+                               &&(!strcasecmp(compare_uid,
+                               conflict_event_uid))) ? 1 : 0
+                       )
+               );
+       }
+
+}
+
+
+
 /*
- * Backend for ical_hunt_for_conflicts()
+ * Phase 5 of "hunt for conflicts"
+ * Called by ical_conflicts_phase4()
+ *
+ * We have the proposed event boiled down to start and end times.
+ * Now check it against an existing event. 
  */
-void ical_hunt_for_conflicts_backend(long msgnum, void *data) {
-       icalcomponent *cal;
-       struct CtdlMessage *msg = NULL;
-       struct ical_respond_data ird;
-       struct icaltimetype t1start, t1end, t2start, t2end;
-       icalproperty *p;
+void ical_conflicts_phase5(struct icaltimetype t1start,
+                       struct icaltimetype t1end,
+                       icalcomponent *existing_event,
+                       long existing_msgnum,
+                       char *compare_uid)
+{
        char conflict_event_uid[SIZ];
        char conflict_event_summary[SIZ];
-       char compare_uid[SIZ];
+       struct icaltimetype t2start, t2end;
+       icalproperty *p;
 
-       cal = (icalcomponent *)data;
-       strcpy(compare_uid, "");
+       /* recur variables */
+       icalproperty *rrule = NULL;
+       struct icalrecurrencetype recur;
+       icalrecur_iterator *ritr = NULL;
+       struct icaldurationtype dur;
+       int num_recur = 0;
+       int out_of_scope = 0;
+
+       /* initialization */
        strcpy(conflict_event_uid, "");
        strcpy(conflict_event_summary, "");
+       t2start = icaltime_null_time();
+       t2end = icaltime_null_time();
 
-       msg = CtdlFetchMessage(msgnum, 1);
-       if (msg == NULL) return;
-       memset(&ird, 0, sizeof ird);
-       strcpy(ird.desired_partnum, "_HUNT_");
-       mime_parser(msg->cm_fields['M'],
-               NULL,
-               *ical_locate_part,              /* callback function */
-               NULL, NULL,
-               (void *) &ird,                  /* user data */
-               0
-       );
-       CtdlFreeMessage(msg);
+       /* existing event stuff */
+       p = ical_ctdl_get_subprop(existing_event, ICAL_DTSTART_PROPERTY);
+       if (p == NULL) return;
+       if (p != NULL) t2start = icalproperty_get_dtstart(p);
 
-       if (ird.cal == NULL) return;
+       p = ical_ctdl_get_subprop(existing_event, ICAL_DTEND_PROPERTY);
+       if (p != NULL) {
+               t2end = icalproperty_get_dtend(p);
+               dur = icaltime_subtract(t2end, t2start);
+       }
 
+       rrule = ical_ctdl_get_subprop(existing_event, ICAL_RRULE_PROPERTY);
+       if (rrule) {
+               recur = icalproperty_get_rrule(rrule);
+               ritr = icalrecur_iterator_new(recur, t2start);
+               CtdlLogPrintf(CTDL_DEBUG, "Recurrence found: %s\n", icalrecurrencetype_as_string(&recur));
+       }
+
+       do {
+               p = ical_ctdl_get_subprop(existing_event, ICAL_UID_PROPERTY);
+               if (p != NULL) {
+                       strcpy(conflict_event_uid, icalproperty_get_comment(p));
+               }
+       
+               p = ical_ctdl_get_subprop(existing_event, ICAL_SUMMARY_PROPERTY);
+               if (p != NULL) {
+                       strcpy(conflict_event_summary, icalproperty_get_comment(p));
+               }
+       
+               ical_conflicts_phase6(t1start, t1end, t2start, t2end,
+                       existing_msgnum, conflict_event_uid, conflict_event_summary, compare_uid
+               );
+
+               if (rrule) {
+                       t2start = icalrecur_iterator_next(ritr);
+                       if (!icaltime_is_null_time(t2end)) {
+                               t2end = icaltime_add(t2start, dur);
+                       }
+                       ++num_recur;
+               }
+
+               if (icaltime_compare(t2start, t1end) < 0) {
+                       CtdlLogPrintf(CTDL_DEBUG, "Went out of scope after %d iterations\n", num_recur);
+                       out_of_scope = 1;
+               }
+
+       } while ((rrule) && (!icaltime_is_null_time(t2start)) && (num_recur < MAX_RECUR) && (!out_of_scope));
+       icalrecur_iterator_free(ritr);
+       if (num_recur > 0) CtdlLogPrintf(CTDL_DEBUG, "Iterated over existing event %d times.\n", num_recur);
+}
+
+
+
+
+/*
+ * Phase 4 of "hunt for conflicts"
+ * Called by ical_hunt_for_conflicts_backend()
+ *
+ * At this point we've got it boiled down to two icalcomponent events in memory.
+ * If they conflict, output something to the client.
+ */
+void ical_conflicts_phase4(icalcomponent *proposed_event,
+               icalcomponent *existing_event,
+               long existing_msgnum)
+{
+       struct icaltimetype t1start, t1end;
        t1start = icaltime_null_time();
        t1end = icaltime_null_time();
-       t2start = icaltime_null_time();
-       t1end = icaltime_null_time();
+       icalproperty *p;
+       char compare_uid[SIZ];
 
-       /* Now compare cal to ird.cal */
-       p = ical_ctdl_get_subprop(ird.cal, ICAL_DTSTART_PROPERTY);
-       if (p == NULL) return;
-       if (p != NULL) t2start = icalproperty_get_dtstart(p);
-       
-       p = ical_ctdl_get_subprop(ird.cal, ICAL_DTEND_PROPERTY);
-       if (p != NULL) t2end = icalproperty_get_dtend(p);
+       /* recur variables */
+       icalproperty *rrule = NULL;
+       struct icalrecurrencetype recur;
+       icalrecur_iterator *ritr = NULL;
+       struct icaldurationtype dur;
+       int num_recur = 0;
+
+       /* initialization */
+       strcpy(compare_uid, "");
 
-       p = ical_ctdl_get_subprop(cal, ICAL_DTSTART_PROPERTY);
+       /* proposed event stuff */
+
+       p = ical_ctdl_get_subprop(proposed_event, ICAL_DTSTART_PROPERTY);
        if (p == NULL) return;
        if (p != NULL) t1start = icalproperty_get_dtstart(p);
        
-       p = ical_ctdl_get_subprop(cal, ICAL_DTEND_PROPERTY);
-       if (p != NULL) t1end = icalproperty_get_dtend(p);
-       
-       p = ical_ctdl_get_subprop(cal, ICAL_UID_PROPERTY);
+       p = ical_ctdl_get_subprop(proposed_event, ICAL_DTEND_PROPERTY);
        if (p != NULL) {
-               strcpy(compare_uid, icalproperty_get_comment(p));
+               t1end = icalproperty_get_dtend(p);
+               dur = icaltime_subtract(t1end, t1start);
        }
 
-       p = ical_ctdl_get_subprop(ird.cal, ICAL_UID_PROPERTY);
-       if (p != NULL) {
-               strcpy(conflict_event_uid, icalproperty_get_comment(p));
+       rrule = ical_ctdl_get_subprop(proposed_event, ICAL_RRULE_PROPERTY);
+       if (rrule) {
+               recur = icalproperty_get_rrule(rrule);
+               ritr = icalrecur_iterator_new(recur, t1start);
+               CtdlLogPrintf(CTDL_DEBUG, "Recurrence found: %s\n", icalrecurrencetype_as_string(&recur));
        }
 
-       p = ical_ctdl_get_subprop(ird.cal, ICAL_SUMMARY_PROPERTY);
+       p = ical_ctdl_get_subprop(proposed_event, ICAL_UID_PROPERTY);
        if (p != NULL) {
-               strcpy(conflict_event_summary, icalproperty_get_comment(p));
+               strcpy(compare_uid, icalproperty_get_comment(p));
        }
 
-       icalcomponent_free(ird.cal);
+       do {
+               ical_conflicts_phase5(t1start, t1end, existing_event, existing_msgnum, compare_uid);
 
-       if (ical_ctdl_is_overlap(t1start, t1end, t2start, t2end)) {
-               cprintf("%ld||%s|%s|%d|\n",
-                       msgnum,
-                       conflict_event_uid,
-                       conflict_event_summary,
-                       (       ((strlen(compare_uid)>0)
-                               &&(!strcasecmp(compare_uid,
-                               conflict_event_uid))) ? 1 : 0
-                       )
-               );
-       }
+               if (rrule) {
+                       t1start = icalrecur_iterator_next(ritr);
+                       if (!icaltime_is_null_time(t1end)) {
+                               t1end = icaltime_add(t1start, dur);
+                       }
+                       ++num_recur;
+               }
+
+       } while ( (rrule) && (!icaltime_is_null_time(t1start)) && (num_recur < MAX_RECUR) );
+       icalrecur_iterator_free(ritr);
+       if (num_recur > 0) CtdlLogPrintf(CTDL_DEBUG, "Iterated over proposed event %d times.\n", num_recur);
+}
+
+
+
+/*
+ * Phase 3 of "hunt for conflicts"
+ * Called by ical_hunt_for_conflicts()
+ */
+void ical_hunt_for_conflicts_backend(long msgnum, void *data) {
+       icalcomponent *proposed_event;
+       struct CtdlMessage *msg = NULL;
+       struct ical_respond_data ird;
+
+       proposed_event = (icalcomponent *)data;
+
+       msg = CtdlFetchMessage(msgnum, 1);
+       if (msg == NULL) return;
+       memset(&ird, 0, sizeof ird);
+       strcpy(ird.desired_partnum, "_HUNT_");
+       mime_parser(msg->cm_fields['M'],
+               NULL,
+               *ical_locate_part,              /* callback function */
+               NULL, NULL,
+               (void *) &ird,                  /* user data */
+               0
+       );
+       CtdlFreeMessage(msg);
+
+       if (ird.cal == NULL) return;
+
+       ical_conflicts_phase4(proposed_event, ird.cal, msgnum);
+       icalcomponent_free(ird.cal);
 }
 
 
@@ -978,7 +1089,7 @@ void ical_hunt_for_conflicts_backend(long msgnum, void *data) {
 /* 
  * Phase 2 of "hunt for conflicts" operation.
  * At this point we have a calendar object which represents the VEVENT that
- * we're considering adding to the calendar.  Now hunt through the user's
+ * is proposed for addition to the calendar.  Now hunt through the user's
  * calendar room, and output zero or more existing VEVENTs which conflict
  * with this one.
  */
@@ -1072,8 +1183,6 @@ void ical_add_to_freebusy(icalcomponent *fb, icalcomponent *cal) {
                return;
        }
 
-       ical_dezonify(cal);
-
        /* If this event is not opaque, the user isn't publishing it as
         * busy time, so don't bother doing anything else.
         */
@@ -1329,7 +1438,7 @@ void ical_freebusy(char *who) {
 
        /* Serialize it */
        CtdlLogPrintf(CTDL_DEBUG, "Serializing\n");
-       serialized_request = strdup(icalcomponent_as_ical_string(encaps));
+       serialized_request = icalcomponent_as_ical_string_r(encaps);
        icalcomponent_free(encaps);     /* Don't need this anymore. */
 
        cprintf("%d Here is the free/busy data:\n", LISTING_FOLLOWS);
@@ -1395,7 +1504,24 @@ void ical_getics_backend(long msgnum, void *data) {
                for (c = icalcomponent_get_first_component(ird.cal, ICAL_ANY_COMPONENT);
                    (c != NULL);
                    c = icalcomponent_get_next_component(ird.cal, ICAL_ANY_COMPONENT)) {
-                       icalcomponent_add_component(encaps, icalcomponent_new_clone(c));
+
+                       /* For VTIMEZONE components, suppress duplicates of the same tzid */
+
+                       if (icalcomponent_isa(c) == ICAL_VTIMEZONE_COMPONENT) {
+                               icalproperty *p = icalcomponent_get_first_property(c, ICAL_TZID_PROPERTY);
+                               if (p) {
+                                       const char *tzid = icalproperty_get_tzid(p);
+                                       if (!icalcomponent_get_timezone(encaps, tzid)) {
+                                               icalcomponent_add_component(encaps,
+                                                                       icalcomponent_new_clone(c));
+                                       }
+                               }
+                       }
+
+                       /* All other types of components can go in verbatim */
+                       else {
+                               icalcomponent_add_component(encaps, icalcomponent_new_clone(c));
+                       }
                }
                icalcomponent_free(ird.cal);
        }
@@ -1420,8 +1546,7 @@ void ical_getics(void)
 
        encaps = icalcomponent_new_vcalendar();
        if (encaps == NULL) {
-               CtdlLogPrintf(CTDL_DEBUG, "Error at %s:%d - could not allocate component!\n",
-                       __FILE__, __LINE__);
+               CtdlLogPrintf(CTDL_DEBUG, "ERROR: could not allocate component!\n");
                cprintf("%d Could not allocate memory\n", ERROR+INTERNAL_ERROR);
                return;
        }
@@ -1445,12 +1570,27 @@ void ical_getics(void)
                (void *) encaps
        );
 
-       ser = strdup(icalcomponent_as_ical_string(encaps));
+       ser = icalcomponent_as_ical_string_r(encaps);
+       icalcomponent_free(encaps);                     /* Don't need this anymore. */
        client_write(ser, strlen(ser));
        free(ser);
        cprintf("\n000\n");
-       icalcomponent_free(encaps);     /* Don't need this anymore. */
+}
 
+
+/*
+ * Helper callback function for ical_putics() to discover which TZID's we need.
+ * Simply put the tzid name string into a hash table.  After the callbacks are
+ * done we'll go through them and attach the ones that we have.
+ */
+void ical_putics_grabtzids(icalparameter *param, void *data)
+{
+       const char *tzid = icalparameter_get_tzid(param);
+       HashList *keys = (HashList *) data;
+       
+       if ( (keys) && (tzid) && (!IsEmptyStr(tzid)) ) {
+               Put(keys, tzid, strlen(tzid), strdup(tzid), generic_free_handler);
+       }
 }
 
 
@@ -1463,13 +1603,21 @@ void ical_putics(void)
        char *calstream = NULL;
        icalcomponent *cal;
        icalcomponent *c;
+       icalcomponent *encaps = NULL;
+       HashList *tzidlist = NULL;
+       HashPos *HashPos;
+       void *Value;
+       const char *Key;
+       long len;
 
+       /* Only allow this operation if we're in a room containing a calendar or tasks view */
        if ( (CC->room.QRdefaultview != VIEW_CALENDAR)
           &&(CC->room.QRdefaultview != VIEW_TASKS) ) {
                cprintf("%d Not a calendar room\n", ERROR+NOT_HERE);
-               return;         /* Not an iCalendar-centric room */
+               return;
        }
 
+       /* Only allow this operation if we have permission to overwrite the existing calendar */
        if (!CtdlDoIHavePermissionToDeleteMessagesFromThisRoom()) {
                cprintf("%d Permission denied.\n", ERROR+HIGHER_ACCESS_REQUIRED);
                return;
@@ -1483,11 +1631,10 @@ void ical_putics(void)
 
        cal = icalcomponent_new_from_string(calstream);
        free(calstream);
-       ical_dezonify(cal);
 
        /* We got our data stream -- now do something with it. */
 
-       /* Delete the existing messages in the room, because we are replacing
+       /* Delete the existing messages in the room, because we are overwriting
         * the entire calendar with an entire new (or updated) calendar.
         * (Careful: this opens an S_ROOMS critical section!)
         */
@@ -1507,7 +1654,55 @@ void ical_putics(void)
                for (c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
                    (c != NULL);
                    c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)) {
-                       ical_write_to_cal(NULL, c);
+
+                       /* Non-VTIMEZONE components each get written as individual messages.
+                        * But we also need to attach the relevant VTIMEZONE components to them.
+                        */
+                       if ( (icalcomponent_isa(c) != ICAL_VTIMEZONE_COMPONENT)
+                          && (encaps = icalcomponent_new_vcalendar()) ) {
+                               icalcomponent_add_property(encaps, icalproperty_new_prodid(PRODID));
+                               icalcomponent_add_property(encaps, icalproperty_new_version("2.0"));
+                               icalcomponent_set_method(encaps, ICAL_METHOD_PUBLISH);
+
+                               /* Attach any needed timezones here */
+                               tzidlist = NewHash(1, NULL);
+                               if (tzidlist) {
+                                       icalcomponent_foreach_tzid(c, ical_putics_grabtzids, tzidlist);
+                               }
+                               HashPos = GetNewHashPos(tzidlist, 0);
+
+                               while (GetNextHashPos(tzidlist, HashPos, &len, &Key, &Value)) {
+                                       CtdlLogPrintf(CTDL_DEBUG, "Attaching timezone '%s'\n", Value);
+                                       icaltimezone *t = NULL;
+
+                                       /* First look for a timezone attached to the original calendar */
+                                       t = icalcomponent_get_timezone(cal, Value);
+
+                                       /* Try built-in tzdata if the right one wasn't attached */
+                                       if (!t) {
+                                               t = icaltimezone_get_builtin_timezone(Value);
+                                       }
+
+                                       /* I've got a valid timezone to attach. */
+                                       if (t) {
+                                               icalcomponent_add_component(encaps,
+                                                       icalcomponent_new_clone(
+                                                               icaltimezone_get_component(t)
+                                                       )
+                                               );
+                                       }
+
+                               }
+                               DeleteHashPos(&HashPos);
+                               DeleteHash(&tzidlist);
+
+                               /* Now attach the component itself (usually a VEVENT or VTODO) */
+                               icalcomponent_add_component(encaps, icalcomponent_new_clone(c));
+
+                               /* Write it to the message store */
+                               ical_write_to_cal(NULL, encaps);
+                               icalcomponent_free(encaps);
+                       }
                }
        }
 
@@ -1653,10 +1848,14 @@ void ical_create_room(void)
 
 
 /*
- * ical_send_out_invitations() is called by ical_saving_vevent() when it
- * finds a VEVENT.
+ * ical_send_out_invitations() is called by ical_saving_vevent() when it finds a VEVENT.
+ *
+ * top_level_cal is the highest available level calendar object.
+ * cal is the subcomponent containing the VEVENT.
+ *
+ * Note: if you change the encapsulation code here, change it in WebCit's ical_encapsulate_subcomponent()
  */
-void ical_send_out_invitations(icalcomponent *cal) {
+void ical_send_out_invitations(icalcomponent *top_level_cal, icalcomponent *cal) {
        icalcomponent *the_request = NULL;
        char *serialized_request = NULL;
        icalcomponent *encaps = NULL;
@@ -1670,6 +1869,13 @@ void ical_send_out_invitations(icalcomponent *cal) {
        char summary_string[SIZ];
        icalproperty *summary = NULL;
        size_t reqsize;
+       icalproperty *p;
+       struct icaltimetype t;
+       icaltimezone *attached_zones[5] = { NULL, NULL, NULL, NULL, NULL };
+       int i;
+       icaltimezone *z;
+       int num_zones_attached = 0;
+       int zone_already_attached;
 
        if (cal == NULL) {
                CtdlLogPrintf(CTDL_ERR, "ERROR: trying to reply to NULL event?\n");
@@ -1679,7 +1885,7 @@ void ical_send_out_invitations(icalcomponent *cal) {
 
        /* If this is a VCALENDAR component, look for a VEVENT subcomponent. */
        if (icalcomponent_isa(cal) == ICAL_VCALENDAR_COMPONENT) {
-               ical_send_out_invitations(
+               ical_send_out_invitations(top_level_cal,
                        icalcomponent_get_first_component(
                                cal, ICAL_VEVENT_COMPONENT
                        )
@@ -1739,8 +1945,7 @@ void ical_send_out_invitations(icalcomponent *cal) {
        /* Encapsulate the VEVENT component into a complete VCALENDAR */
        encaps = icalcomponent_new_vcalendar();
        if (encaps == NULL) {
-               CtdlLogPrintf(CTDL_DEBUG, "Error at %s:%d - could not allocate component!\n",
-                       __FILE__, __LINE__);
+               CtdlLogPrintf(CTDL_DEBUG, "ERROR: could not allocate component!\n");
                icalcomponent_free(the_request);
                return;
        }
@@ -1754,20 +1959,101 @@ void ical_send_out_invitations(icalcomponent *cal) {
        /* Set the method to REQUEST */
        icalcomponent_set_method(encaps, ICAL_METHOD_REQUEST);
 
-       /* Now make sure all of the DTSTART and DTEND properties are UTC. */
-       ical_dezonify(the_request);
+       /* Look for properties containing timezone parameters, to see if we need to attach VTIMEZONEs */
+       for (p = icalcomponent_get_first_property(the_request, ICAL_ANY_PROPERTY);
+            p != NULL;
+            p = icalcomponent_get_next_property(the_request, ICAL_ANY_PROPERTY))
+       {
+               if ( (icalproperty_isa(p) == ICAL_COMPLETED_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_CREATED_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_DATEMAX_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_DATEMIN_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_DTEND_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_DTSTAMP_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_DTSTART_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_DUE_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_EXDATE_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_LASTMODIFIED_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_MAXDATE_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_MINDATE_PROPERTY)
+                 || (icalproperty_isa(p) == ICAL_RECURRENCEID_PROPERTY)
+               ) {
+                       t = icalproperty_get_dtstart(p);        // it's safe to use dtstart for all of them
+                       CtdlLogPrintf(CTDL_DEBUG, "Found an icaltimetype: %s\n",
+                               icaltime_as_ical_string(t)
+                       );
+
+                       /* First see if there's a timezone attached to the data structure itself */
+                       if (icaltime_is_utc(t)) {
+                               z = icaltimezone_get_utc_timezone();
+                       }
+                       else {
+                               z = icaltime_get_timezone(t);
+                       }
+                       if (z) CtdlLogPrintf(CTDL_DEBUG, "Timezone is present in data structure\n");
+
+                       /* If not, try to determine the tzid from the parameter using attached zones */
+                       if (!z) {
+                               z = icalcomponent_get_timezone(top_level_cal,
+                                       icalparameter_get_tzid(
+                                               icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER)
+                                       )
+                               );
+                               if (z) CtdlLogPrintf(CTDL_DEBUG, "Timezone was found in attached zones\n");
+                       }
+
+                       /* Still no good?  Try our internal database */
+                       if (!z) {
+                               z = icaltimezone_get_builtin_timezone_from_tzid(
+                                       icalparameter_get_tzid(
+                                               icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER)
+                                       )
+                               );
+                               if (z) CtdlLogPrintf(CTDL_DEBUG, "Timezone was found in internal db\n");
+                       }
 
-       /* Here we go: put the VEVENT into the VCALENDAR.  We now no longer
+                       if (z) {
+                               CtdlLogPrintf(CTDL_DEBUG, "Have valid timezone, need to attach it.\n");
+
+                               zone_already_attached = 0;
+                               for (i=0; i<5; ++i) {
+                                       if (z == attached_zones[i]) {
+                                               ++zone_already_attached;
+                                               CtdlLogPrintf(CTDL_DEBUG, "zone already attached!!\n");
+                                       }
+                               }
+                               if ((!zone_already_attached) && (num_zones_attached < 5)) {
+                                       CtdlLogPrintf(CTDL_DEBUG, "attach zone %d\n", num_zones_attached);
+                                       attached_zones[num_zones_attached++] = z;
+                               }
+
+                               icalproperty_set_parameter(p,
+                                       icalparameter_new_tzid(icaltimezone_get_tzid(z))
+                               );
+                       }
+               }
+       }
+
+       /* Encapsulate any timezones we need */
+       if (num_zones_attached > 0) for (i=0; i<num_zones_attached; ++i) {
+               icalcomponent *zc;
+               zc = icalcomponent_new_clone(icaltimezone_get_component(attached_zones[i]));
+               icalcomponent_add_component(encaps, zc);
+       }
+
+       /* Here we go: encapsulate the VEVENT into the VCALENDAR.  We now no longer
         * are responsible for "the_request"'s memory -- it will be freed
         * when we free "encaps".
         */
        icalcomponent_add_component(encaps, the_request);
 
        /* Serialize it */
-       serialized_request = strdup(icalcomponent_as_ical_string(encaps));
+       serialized_request = icalcomponent_as_ical_string_r(encaps);
        icalcomponent_free(encaps);     /* Don't need this anymore. */
        if (serialized_request == NULL) return;
 
+       CtdlLogPrintf(CTDL_DEBUG, "SENDING INVITATIONS:\n%s\n", serialized_request);
+
        reqsize = strlen(serialized_request) + SIZ;
        request_message_text = malloc(reqsize);
        if (request_message_text != NULL) {
@@ -1803,8 +2089,13 @@ void ical_send_out_invitations(icalcomponent *cal) {
  * and the user saving it is the organizer.  If so, send out invitations
  * to any listed attendees.
  *
+ * This function is recursive.  The caller can simply supply the same object
+ * as both arguments.  When it recurses it will alter the second argument
+ * while holding on to the top level object.  This allows us to go back and
+ * grab things like time zones which might be attached.
+ *
  */
-void ical_saving_vevent(icalcomponent *cal) {
+void ical_saving_vevent(icalcomponent *top_level_cal, icalcomponent *cal) {
        icalcomponent *c;
        icalproperty *organizer = NULL;
        char organizer_string[SIZ];
@@ -1842,7 +2133,7 @@ void ical_saving_vevent(icalcomponent *cal) {
                         * organizer, then send out invitations.
                         */
                        if (CtdlIsMe(organizer_string, sizeof organizer_string)) {
-                               ical_send_out_invitations(cal);
+                               ical_send_out_invitations(top_level_cal, cal);
                        }
                }
        }
@@ -1852,7 +2143,7 @@ void ical_saving_vevent(icalcomponent *cal) {
            (c != NULL);
            c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)) {
                /* Recursively process subcomponent */
-               ical_saving_vevent(c);
+               ical_saving_vevent(top_level_cal, c);
        }
 
 }
@@ -1867,7 +2158,7 @@ void ical_saving_vevent(icalcomponent *cal) {
  */
 void ical_obj_beforesave_backend(char *name, char *filename, char *partnum,
                char *disp, void *content, char *cbtype, char *cbcharset, size_t length,
-               char *encoding, void *cbuserdata)
+               char *encoding, char *cbid, void *cbuserdata)
 {
        icalcomponent *cal, *nested_event, *nested_todo, *whole_cal;
        icalproperty *p;
@@ -2011,7 +2302,7 @@ int ical_obj_beforesave(struct CtdlMessage *msg)
  */
 void ical_obj_aftersave_backend(char *name, char *filename, char *partnum,
                char *disp, void *content, char *cbtype, char *cbcharset, size_t length,
-               char *encoding, void *cbuserdata)
+               char *encoding, char *cbid, void *cbuserdata)
 {
        icalcomponent *cal;
 
@@ -2030,7 +2321,7 @@ void ical_obj_aftersave_backend(char *name, char *filename, char *partnum,
           || (!strcasecmp(cbtype, "application/ics")) ) {
                cal = icalcomponent_new_from_string(content);
                if (cal != NULL) {
-                       ical_saving_vevent(cal);
+                       ical_saving_vevent(cal, cal);
                        icalcomponent_free(cal);
                }
        }
@@ -2152,7 +2443,6 @@ void ical_fixed_output(char *ptr, int len) {
                return;
        }
 
-       ical_dezonify(cal);
        ical_fixed_output_backend(cal, 0);
 
        /* Free the memory we obtained from libical's constructor */
@@ -2173,6 +2463,14 @@ CTDL_MODULE_INIT(calendar)
 {
        if (!threading)
        {
+
+               /* Tell libical to return errors instead of aborting if it gets bad data */
+               icalerror_errors_are_fatal = 0;
+
+               /* Use our own application prefix in tzid's generated from system tzdata */
+               icaltimezone_set_tzid_prefix("/citadel.org/");
+
+               /* Initialize our hook functions */
                CtdlRegisterMessageHook(ical_obj_beforesave, EVT_BEFORESAVE);
                CtdlRegisterMessageHook(ical_obj_aftersave, EVT_AFTERSAVE);
                CtdlRegisterSessionHook(ical_create_room, EVT_LOGIN);
@@ -2187,4 +2485,3 @@ CTDL_MODULE_INIT(calendar)
        /* return our Subversion id for the Log */
        return "$Id$";
 }
-