Make chaos calendar gem

1 files changed, 76 insertions, 0 deletions

diff --git a/lib/chaos_calendar/chaos_calendar.c b/lib/chaos_calendar/chaos_calendar.c
new file mode 100644
index 00000000..e59c1ed4
--- /dev/null
+++ b/lib/chaos_calendar/chaos_calendar.c
@@ -0,0 +1,76 @@
+#include <ruby.h>
+#include <ical.h>
+#include <time.h>
+
+//#define RRULE   "FREQ=MONTHLY;BYMONTH=1,2,3,4,5,6,7,8,9,10,11;BYDAY=-1WE;UNTIL=20091105T220000"
+//#define RRULE   "FREQ=DAILY;UNTIL=20991111T220000;VFOO"
+
+VALUE occurrences( VALUE dtstart, VALUE dtend, char *rrule ) {
+  struct icaltimetype start, end;
+  time_t tt;
+  VALUE  tv_sec, occurr = rb_ary_new(); 
+
+  /* Get method ID for Time.tv_sec */
+  ID time_tv_sec  = rb_intern( "tv_sec" );
+  ID time_to_time = rb_intern( "to_time" );
+
+  if( !rb_respond_to( dtstart, time_tv_sec ) ) {
+    if( rb_respond_to( dtstart, time_to_time ) )
+      dtstart = rb_funcall( dtstart, time_to_time, 0 );
+    else
+     rb_raise( rb_eTypeError, "Can't convert dtstart into a Time-like object." );
+  }
+
+  if( !rb_respond_to( dtend, time_tv_sec ) ) {
+    if( rb_respond_to( dtend, time_to_time ) ) 
+      dtend = rb_funcall( dtend, time_to_time, 0 );
+    else
+     rb_raise( rb_eTypeError, "Can't convert dtend into a Time-like object." );
+  }
+
+  /* Apply .tv_sec to our Time objects (if they are Times ...) */
+  tv_sec = rb_funcall( dtstart, time_tv_sec, 0 ); 
+  tt     = NUM2INT( tv_sec );
+  start  = icaltime_from_timet( tt, 0 );
+
+  tv_sec = rb_funcall( dtend, time_tv_sec, 0 );
+  tt     = NUM2INT( tv_sec );
+  end    = icaltime_from_timet( tt, 0 );
+
+  icalerror_clear_errno();
+  icalerror_set_error_state( ICAL_MALFORMEDDATA_ERROR, ICAL_ERROR_NONFATAL);
+
+  struct icalrecurrencetype recur = icalrecurrencetype_from_string( rrule );
+  if( icalerrno != ICAL_NO_ERROR ) {
+    rb_raise(rb_eArgError, "Malformed RRule");
+    return Qnil;
+  }
+
+  icalrecur_iterator* ritr = icalrecur_iterator_new( recur, start );
+
+  while(1) {
+    struct icaltimetype next = icalrecur_iterator_next(ritr);
+
+    if( icaltime_is_null_time(next) || ( icaltime_compare( next, end ) > 0 ) ) {
+      icalrecur_iterator_free(ritr);
+      return occurr; 
+    }
+
+    rb_ary_push( occurr, rb_time_new( icaltime_as_timet( next ), 0 ) );
+  };
+
+  icalrecur_iterator_free(ritr);
+  return occurr;
+}
+
+VALUE duration_to_fixnum( char * duration ) {
+  icalerror_clear_errno();
+  icalerror_set_error_state( ICAL_MALFORMEDDATA_ERROR, ICAL_ERROR_NONFATAL);
+
+  struct icaldurationtype dur_struct = icaldurationtype_from_string( duration );
+
+  if( icaldurationtype_is_bad_duration( dur_struct ) )
+    rb_raise(rb_eArgError, "Malformed Duration");
+
+  return LONG2FIX(icaldurationtype_as_int( dur_struct ));
+}