#include <assert.h>
#include <stdlib.h>

#include <libical/ical.h>

char *
read_stream(char *s, size_t size, void *d)
{
	return fgets(s, (int)size, (FILE *)d);
}

int
main(void)
{
	icalparser *parser = icalparser_new();
	assert(parser);

	FILE *stream = stdin;
	assert(stream);

	icalparser_set_gen_data(parser, stream);
	for (;;) {
		char *line = icalparser_get_line(parser, read_stream);
		if (!line) {
			break;
		}

		icalcomponent *comp = icalparser_add_line(parser, line);
		if (!comp) {
			continue;
		}

		for (icalcompiter i = icalcomponent_begin_component(
			 comp, ICAL_VEVENT_COMPONENT);
		     icalcompiter_deref(&i); icalcompiter_next(&i)) {
			icalcomponent *c = icalcompiter_deref(&i);

			struct icaltimetype dts = icalcomponent_get_dtstart(c);
			icaltimezone *utc = icaltimezone_get_utc_timezone();
			dts = icaltime_convert_to_zone(dts, utc);
			printf("%02u-%02u-%02u  ", dts.year, dts.month,
			       dts.day);
			printf("%02u:%02u  ", dts.hour, dts.minute);

			const char *sum = icalcomponent_get_summary(c);
			if (sum)
				printf("%s\n", sum);
		}

		icalcomponent_free(comp);
	}

	icalparser_free(parser);
}