webcit/availability.c

   1 /*
   2  * $Id$
   3  */
   4 /**
   5  *
   6  * \defgroup CalendarAv  Check attendee availability for scheduling a meeting.
   7  * \ingroup Calendaring
   8  */
   9 /*@{*/
  10
  11
  12 #include "webcit.h"
  13 #include "webserver.h"
  14
  15 /** only available if we have calendaring */
  16 #ifdef WEBCIT_WITH_CALENDAR_SERVICE
  17
  18
  19
  20 /**
  21  * \brief verify users avaiability
  22  * Utility function to fetch a VFREEBUSY type of thing for
  23  * any specified user.
  24  * \param who string of the user to search
  25  */
  26 icalcomponent *get_freebusy_for_user(char *who) {
  27         char buf[SIZ];
  28         char *serialized_fb = NULL;
  29         icalcomponent *fb = NULL;
  30
  31         serv_printf("ICAL freebusy|%s", who);
  32         serv_getln(buf, sizeof buf);
  33         if (buf[0] == '1') {
  34                 serialized_fb = read_server_text();
  35         }
  36
  37         if (serialized_fb == NULL) {
  38                 return NULL;
  39         }
  40
  41         fb = icalcomponent_new_from_string(serialized_fb);
  42         free(serialized_fb);
  43         if (fb == NULL) {
  44                 return NULL;
  45         }
  46
  47         return(fb);
  48 }
  49
  50
  51
  52
  53 /**
  54  * \brief Check if dates are overlapping
  55  * Check to see if two events overlap.
  56  * (This function is used in both Citadel and WebCit.  If you change it in
  57  * one place, change it in the other.  Better yet, put it in a library.)
  58  * \param t1start date one start
  59  * \param t1end  date one end
  60  * \param t2start date one start
  61  * \param t2end date two end
  62  * \returns nonzero if they do.
  63  */
  64 int ical_ctdl_is_overlap(
  65                         struct icaltimetype t1start,
  66                         struct icaltimetype t1end,
  67                         struct icaltimetype t2start,
  68                         struct icaltimetype t2end
  69 ) {
  70
  71         if (icaltime_is_null_time(t1start)) return(0);
  72         if (icaltime_is_null_time(t2start)) return(0);
  73
  74         /** First, check for all-day events */
  75         if (t1start.is_date) {
  76                 if (!icaltime_compare_date_only(t1start, t2start)) {
  77                         return(1);
  78                 }
  79                 if (!icaltime_is_null_time(t2end)) {
  80                         if (!icaltime_compare_date_only(t1start, t2end)) {
  81                                 return(1);
  82                         }
  83                 }
  84         }
  85
  86         if (t2start.is_date) {
  87                 if (!icaltime_compare_date_only(t2start, t1start)) {
  88                         return(1);
  89                 }
  90                 if (!icaltime_is_null_time(t1end)) {
  91                         if (!icaltime_compare_date_only(t2start, t1end)) {
  92                                 return(1);
  93                         }
  94                 }
  95         }
  96
  97         /** Now check for overlaps using date *and* time. */
  98
  99         /** First, bail out if either event 1 or event 2 is missing end time. */
 100         if (icaltime_is_null_time(t1end)) return(0);
 101         if (icaltime_is_null_time(t2end)) return(0);
 102
 103         /** If event 1 ends before event 2 starts, we're in the clear. */
 104         if (icaltime_compare(t1end, t2start) <= 0) return(0);
 105
 106         /** If event 2 ends before event 1 starts, we're also ok. */
 107         if (icaltime_compare(t2end, t1start) <= 0) return(0);
 108
 109         /** Otherwise, they overlap. */
 110         return(1);
 111 }
 112
 113
 114
 115 /*
 116  * \brief dig availability on citserver
 117  * Back end function for check_attendee_availability()
 118  * This one checks an individual attendee against a supplied
 119  * event start and end time.  All these fields have already been
 120  * broken out.
 121  * \param attendee_string name of the attendee
 122  * \param event_start starttime of the event to check
 123  * \param event_end endtime of the event to check
 124  * \return The result is placed in 'annotation'.
 125  */
 126 void check_individual_attendee(char *attendee_string,
 127                                 struct icaltimetype event_start,
 128                                 struct icaltimetype event_end,
 129                                 char *annotation) {
 130
 131         icalcomponent *fbc = NULL;
 132         icalcomponent *fb = NULL;
 133         icalproperty *thisfb = NULL;
 134         struct icalperiodtype period;
 135
 136         /**
 137          * Set to 'unknown' right from the beginning.  Unless we learn
 138          * something else, that's what we'll go with.
 139          */
 140         strcpy(annotation, _("availability unknown"));
 141
 142         fbc = get_freebusy_for_user(attendee_string);
 143         if (fbc == NULL) {
 144                 return;
 145         }
 146
 147         /**
 148          * Make sure we're looking at a VFREEBUSY by itself.  What we're probably
 149          * looking at initially is a VFREEBUSY encapsulated in a VCALENDAR.
 150          */
 151         if (icalcomponent_isa(fbc) == ICAL_VCALENDAR_COMPONENT) {
 152                 fb = icalcomponent_get_first_component(fbc, ICAL_VFREEBUSY_COMPONENT);
 153         }
 154         else if (icalcomponent_isa(fbc) == ICAL_VFREEBUSY_COMPONENT) {
 155                 fb = fbc;
 156         }
 157
 158         /** Iterate through all FREEBUSY's looking for conflicts. */
 159         if (fb != NULL) {
 160
 161                 strcpy(annotation, _("free"));
 162
 163                 for (thisfb = icalcomponent_get_first_property(fb, ICAL_FREEBUSY_PROPERTY);
 164                     thisfb != NULL;
 165                     thisfb = icalcomponent_get_next_property(fb, ICAL_FREEBUSY_PROPERTY) ) {
 166
 167                         /** Do the check */
 168                         period = icalproperty_get_freebusy(thisfb);
 169                         if (ical_ctdl_is_overlap(period.start, period.end,
 170                            event_start, event_end)) {
 171                                 strcpy(annotation, _("BUSY"));
 172                         }
 173
 174                 }
 175         }
 176
 177         icalcomponent_free(fbc);
 178 }
 179
 180
 181
 182
 183 /**
 184  * \brief check attendees availability
 185  * Check the availability of all attendees for an event (when possible)
 186  * and annotate accordingly.
 187  * \param vevent the event which should be compared with attendees calendar
 188  */
 189 void check_attendee_availability(icalcomponent *vevent) {
 190         icalproperty *attendee = NULL;
 191         icalproperty *dtstart_p = NULL;
 192         icalproperty *dtend_p = NULL;
 193         struct icaltimetype dtstart_t;
 194         struct icaltimetype dtend_t;
 195         char attendee_string[SIZ];
 196         char annotated_attendee_string[SIZ];
 197         char annotation[SIZ];
 198
 199         if (vevent == NULL) {
 200                 return;
 201         }
 202
 203         /**
 204          * If we're looking at a fully encapsulated VCALENDAR
 205          * rather than a VEVENT component, attempt to use the first
 206          * relevant VEVENT subcomponent.  If there is none, the
 207          * NULL returned by icalcomponent_get_first_component() will
 208          * tell the next iteration of this function to create a
 209          * new one.
 210          */
 211         if (icalcomponent_isa(vevent) == ICAL_VCALENDAR_COMPONENT) {
 212                 check_attendee_availability(
 213                         icalcomponent_get_first_component(
 214                                 vevent, ICAL_VEVENT_COMPONENT
 215                         )
 216                 );
 217                 return;
 218         }
 219
 220         ical_dezonify(vevent);          /**< Convert everything to UTC */
 221
 222         /**
 223          * Learn the start and end times.
 224          */
 225         dtstart_p = icalcomponent_get_first_property(vevent, ICAL_DTSTART_PROPERTY);
 226         if (dtstart_p != NULL) dtstart_t = icalproperty_get_dtstart(dtstart_p);
 227
 228         dtend_p = icalcomponent_get_first_property(vevent, ICAL_DTEND_PROPERTY);
 229         if (dtend_p != NULL) dtend_t = icalproperty_get_dtend(dtend_p);
 230
 231         /**
 232          * Iterate through attendees.
 233          */
 234         for (attendee = icalcomponent_get_first_property(vevent, ICAL_ATTENDEE_PROPERTY);
 235             attendee != NULL;
 236             attendee = icalcomponent_get_next_property(vevent, ICAL_ATTENDEE_PROPERTY)) {
 237
 238                 strcpy(attendee_string, icalproperty_get_attendee(attendee));
 239                 if (!strncasecmp(attendee_string, "MAILTO:", 7)) {
 240
 241                         /** screen name or email address */
 242                         strcpy(attendee_string, &attendee_string[7]);
 243                         striplt(attendee_string);
 244
 245                         check_individual_attendee(attendee_string,
 246                                                 dtstart_t, dtend_t,
 247                                                 annotation);
 248
 249                         /** Replace the attendee name with an annotated one. */
 250                         snprintf(annotated_attendee_string, sizeof annotated_attendee_string,
 251                                 "MAILTO:%s (%s)", attendee_string, annotation);
 252                         icalproperty_set_attendee(attendee, annotated_attendee_string);
 253
 254                 }
 255         }
 256
 257 }
 258
 259
 260 #endif /* WEBCIT_WITH_CALENDAR_SERVICE */
 261
 262 /** @} */