webcit/availability.c

   1 /*
   2  * $Id$
   3  *
   4  */
   5
   6
   7 #include "webcit.h"
   8 #include "webserver.h"
   9
  10 /*
  11  * Utility function to fetch a VFREEBUSY type of thing for any specified user.
  12  */
  13 icalcomponent *get_freebusy_for_user(char *who) {
  14         long nLines;
  15         char buf[SIZ];
  16         StrBuf *serialized_fb = NewStrBuf();
  17         icalcomponent *fb = NULL;
  18
  19         serv_printf("ICAL freebusy|%s", who);
  20         serv_getln(buf, sizeof buf);
  21         if (buf[0] == '1') {
  22                 read_server_text(serialized_fb, &nLines);
  23         }
  24
  25         if (serialized_fb == NULL) {
  26                 return NULL;
  27         }
  28
  29         fb = icalcomponent_new_from_string(ChrPtr(serialized_fb));
  30         FreeStrBuf(&serialized_fb);
  31         if (fb == NULL) {
  32                 return NULL;
  33         }
  34
  35         return(fb);
  36 }
  37
  38
  39 /*
  40  * Check to see if two events overlap.
  41  * (This function is used in both Citadel and WebCit.  If you change it in
  42  * one place, change it in the other.  We should seriously consider moving
  43  * this function upstream into libical.)
  44  *
  45  * Returns nonzero if they do overlap.
  46  */
  47 int ical_ctdl_is_overlap(
  48                         struct icaltimetype t1start,
  49                         struct icaltimetype t1end,
  50                         struct icaltimetype t2start,
  51                         struct icaltimetype t2end
  52 ) {
  53
  54         if (icaltime_is_null_time(t1start)) return(0);
  55         if (icaltime_is_null_time(t2start)) return(0);
  56
  57         /* First, check for all-day events */
  58         if (t1start.is_date) {
  59                 if (!icaltime_compare_date_only(t1start, t2start)) {
  60                         return(1);
  61                 }
  62                 if (!icaltime_is_null_time(t2end)) {
  63                         if (!icaltime_compare_date_only(t1start, t2end)) {
  64                                 return(1);
  65                         }
  66                 }
  67         }
  68
  69         if (t2start.is_date) {
  70                 if (!icaltime_compare_date_only(t2start, t1start)) {
  71                         return(1);
  72                 }
  73                 if (!icaltime_is_null_time(t1end)) {
  74                         if (!icaltime_compare_date_only(t2start, t1end)) {
  75                                 return(1);
  76                         }
  77                 }
  78         }
  79
  80         /* lprintf (9, "Comparing t1start %d:%d t1end %d:%d t2start %d:%d t2end %d:%d \n",
  81                 t1start.hour, t1start.minute, t1end.hour, t1end.minute,
  82                 t2start.hour, t2start.minute, t2end.hour, t2end.minute);
  83         */
  84
  85         /* Now check for overlaps using date *and* time. */
  86
  87         /* First, bail out if either event 1 or event 2 is missing end time. */
  88         if (icaltime_is_null_time(t1end)) return(0);
  89         if (icaltime_is_null_time(t2end)) return(0);
  90
  91         /* If event 1 ends before event 2 starts, we're in the clear. */
  92         if (icaltime_compare(t1end, t2start) <= 0) return(0);
  93         /* lprintf(9, "first passed\n"); */
  94
  95         /* If event 2 ends before event 1 starts, we're also ok. */
  96         if (icaltime_compare(t2end, t1start) <= 0) return(0);
  97         /* lprintf(9, "second passed\n"); */
  98
  99         /* Otherwise, they overlap. */
 100         return(1);
 101 }
 102
 103
 104
 105 /*
 106  * \brief dig availability on citserver
 107  * Back end function for check_attendee_availability()
 108  * This one checks an individual attendee against a supplied
 109  * event start and end time.  All these fields have already been
 110  * broken out.
 111  * \param attendee_string name of the attendee
 112  * \param event_start starttime of the event to check
 113  * \param event_end endtime of the event to check
 114  * \return The result is placed in 'annotation'.
 115  */
 116 void check_individual_attendee(char *attendee_string,
 117                                 struct icaltimetype event_start,
 118                                 struct icaltimetype event_end,
 119                                 char *annotation) {
 120
 121         icalcomponent *fbc = NULL;
 122         icalcomponent *fb = NULL;
 123         icalproperty *thisfb = NULL;
 124         struct icalperiodtype period;
 125
 126         /**
 127          * Set to 'unknown' right from the beginning.  Unless we learn
 128          * something else, that's what we'll go with.
 129          */
 130         strcpy(annotation, _("availability unknown"));
 131
 132         fbc = get_freebusy_for_user(attendee_string);
 133         if (fbc == NULL) {
 134                 return;
 135         }
 136
 137         /**
 138          * Make sure we're looking at a VFREEBUSY by itself.  What we're probably
 139          * looking at initially is a VFREEBUSY encapsulated in a VCALENDAR.
 140          */
 141         if (icalcomponent_isa(fbc) == ICAL_VCALENDAR_COMPONENT) {
 142                 fb = icalcomponent_get_first_component(fbc, ICAL_VFREEBUSY_COMPONENT);
 143         }
 144         else if (icalcomponent_isa(fbc) == ICAL_VFREEBUSY_COMPONENT) {
 145                 fb = fbc;
 146         }
 147
 148         /** Iterate through all FREEBUSY's looking for conflicts. */
 149         if (fb != NULL) {
 150
 151                 strcpy(annotation, _("free"));
 152
 153                 for (thisfb = icalcomponent_get_first_property(fb, ICAL_FREEBUSY_PROPERTY);
 154                     thisfb != NULL;
 155                     thisfb = icalcomponent_get_next_property(fb, ICAL_FREEBUSY_PROPERTY) ) {
 156
 157                         /** Do the check */
 158                         period = icalproperty_get_freebusy(thisfb);
 159                         if (ical_ctdl_is_overlap(period.start, period.end,
 160                            event_start, event_end)) {
 161                                 strcpy(annotation, _("BUSY"));
 162                         }
 163
 164                 }
 165         }
 166
 167         icalcomponent_free(fbc);
 168 }
 169
 170
 171
 172
 173 /**
 174  * \brief check attendees availability
 175  * Check the availability of all attendees for an event (when possible)
 176  * and annotate accordingly.
 177  * \param vevent the event which should be compared with attendees calendar
 178  */
 179 void check_attendee_availability(icalcomponent *vevent) {
 180         icalproperty *attendee = NULL;
 181         icalproperty *dtstart_p = NULL;
 182         icalproperty *dtend_p = NULL;
 183         struct icaltimetype dtstart_t;
 184         struct icaltimetype dtend_t;
 185         char attendee_string[SIZ];
 186         char annotated_attendee_string[SIZ];
 187         char annotation[SIZ];
 188
 189         if (vevent == NULL) {
 190                 return;
 191         }
 192
 193         /**
 194          * If we're looking at a fully encapsulated VCALENDAR
 195          * rather than a VEVENT component, attempt to use the first
 196          * relevant VEVENT subcomponent.  If there is none, the
 197          * NULL returned by icalcomponent_get_first_component() will
 198          * tell the next iteration of this function to create a
 199          * new one.
 200          */
 201         if (icalcomponent_isa(vevent) == ICAL_VCALENDAR_COMPONENT) {
 202                 check_attendee_availability(
 203                         icalcomponent_get_first_component(
 204                                 vevent, ICAL_VEVENT_COMPONENT
 205                         )
 206                 );
 207                 return;
 208         }
 209
 210         ical_dezonify(vevent);          /**< Convert everything to UTC */
 211
 212         /**
 213          * Learn the start and end times.
 214          */
 215         dtstart_p = icalcomponent_get_first_property(vevent, ICAL_DTSTART_PROPERTY);
 216         if (dtstart_p != NULL) dtstart_t = icalproperty_get_dtstart(dtstart_p);
 217
 218         dtend_p = icalcomponent_get_first_property(vevent, ICAL_DTEND_PROPERTY);
 219         if (dtend_p != NULL) dtend_t = icalproperty_get_dtend(dtend_p);
 220
 221         /**
 222          * Iterate through attendees.
 223          */
 224         for (attendee = icalcomponent_get_first_property(vevent, ICAL_ATTENDEE_PROPERTY);
 225             attendee != NULL;
 226             attendee = icalcomponent_get_next_property(vevent, ICAL_ATTENDEE_PROPERTY)) {
 227
 228                 strcpy(attendee_string, icalproperty_get_attendee(attendee));
 229                 if (!strncasecmp(attendee_string, "MAILTO:", 7)) {
 230
 231                         /** screen name or email address */
 232                         strcpy(attendee_string, &attendee_string[7]);
 233                         striplt(attendee_string);
 234
 235                         check_individual_attendee(attendee_string,
 236                                                 dtstart_t, dtend_t,
 237                                                 annotation);
 238
 239                         /** Replace the attendee name with an annotated one. */
 240                         snprintf(annotated_attendee_string, sizeof annotated_attendee_string,
 241                                 "MAILTO:%s (%s)", attendee_string, annotation);
 242                         icalproperty_set_attendee(attendee, annotated_attendee_string);
 243
 244                 }
 245         }
 246
 247 }
 248