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