adding some flags

src/main.c

@@ -1,24 +1,83 @@
 #include <stdio.h>
+#include <string.h>
 #include <time.h>
 #include "church_day.h"
 #include "builder.h"
 
-int main(void) {
+static void print_usage(const char *program_name) {
+	printf("Usage: %s [OPTIONS]\n", program_name);
+	printf("Calculate the church calendar for the current year.\n\n");
+	printf("Options:\n");
+	printf("  --all     Print all days in the liturgical year\n");
+	printf("  --help    Display this help message\n");
+	printf("\nWith no options, prints only today's liturgical day.\n");
+}
+
+static int compare_dates(struct tm d1, struct tm d2) {
+	if (d1.tm_year != d2.tm_year) return d1.tm_year - d2.tm_year;
+	if (d1.tm_mon != d2.tm_mon) return d1.tm_mon - d2.tm_mon;
+	return d1.tm_mday - d2.tm_mday;
+}
+
+int main(int argc, char *argv[]) {
+	int print_all = 0;
+
+	// Parse arguments
+	for (int i = 1; i < argc; i++) {
+		if (strcmp(argv[i], "--all") == 0) {
+			print_all = 1;
+		} else if (strcmp(argv[i], "--help") == 0) {
+			print_usage(argv[0]);
+			return 0;
+		} else {
+			fprintf(stderr, "Unknown option: %s\n", argv[i]);
+			print_usage(argv[0]);
+			return 1;
+		}
+	}
+
 	time_t now = time(NULL);
 	struct tm *today = localtime(&now);
 
 	ChurchYear seasons = proper_of_seasons(*today);
 
-	for (size_t i = 0; i < seasons.count; i++) {
-		ChurchDay *day = &seasons.days[i];
-		printf("%s, %s %d, %d - %s - %s in %s\n",
-	 		church_day_weekday_string(day),
-	 		church_day_month_name(day),
-	 		day->date.tm_mday,
-	 		day->date.tm_year + 1900,
-	 		day->description,
-	 		day_class_to_string(day->class),
-	 		season_to_string(day->season));
+	if (print_all) {
+		// Print all days
+		for (size_t i = 0; i < seasons.count; i++) {
+			ChurchDay *day = &seasons.days[i];
+			printf("%s, %s %d, %d - %s - %s in %s\n",
+				church_day_weekday_string(day),
+				church_day_month_name(day),
+				day->date.tm_mday,
+				day->date.tm_year + 1900,
+				day->description,
+				day_class_to_string(day->class),
+				season_to_string(day->season));
+		}
+	} else {
+		// Print only today
+		ChurchDay *found = NULL;
+		for (size_t i = 0; i < seasons.count; i++) {
+			if (compare_dates(seasons.days[i].date, *today) == 0) {
+				found = &seasons.days[i];
+				break;
+			}
+		}
+
+		if (found) {
+			printf("%s, %s %d, %d - %s - %s in %s\n",
+				church_day_weekday_string(found),
+				church_day_month_name(found),
+				found->date.tm_mday,
+				found->date.tm_year + 1900,
+				found->description,
+				day_class_to_string(found->class),
+				season_to_string(found->season));
+		} else {
+			fprintf(stderr, "Could not find today's date in the liturgical calendar.\n");
+			church_year_free(&seasons);
+			return 1;
+		}
 	}
 
 	church_year_free(&seasons);