implement entry

4 files changed, 209 insertions, 11 deletions

diff --git a/src/calendar.h b/src/calendar.h
index 060ad99..f5f1286 100644
--- a/src/calendar.h
+++ b/src/calendar.h
@@ -1,17 +1,10 @@
 #ifndef EVERY_CALENDAR_H
 #define EVERY_CALENDAR_H
 
-enum calendar_entry_type_e {
-	CALENDAR_ENTRY_TYPE_ON,
-	CALENDAR_ENTRY_TYPE_EVERY,
-};
-
-struct calendar_entry_s {
-	enum calendar_entry_type_e type;
-};
+#include "entry.h"
 
 struct calendar_s {
-	struct calendar_entry_s *entries;
+	struct entry_s *entries;
 };
 
 #endif
diff --git a/src/entry.c b/src/entry.c
new file mode 100644
index 0000000..64acdea
--- /dev/null
+++ b/src/entry.c
@@ -0,0 +1,178 @@
+#include "entry.h"
+
+#include <assert.h>
+
+static int sub_inc_year(struct tm *t, int n)
+{
+	if (n == 0)
+		return 0;
+
+	t->tm_year += n;
+
+	if (mktime(t) == -1)
+		return -1;
+
+	return 0;
+}
+
+static int sub_inc_month(struct tm *t, int n)
+{
+	unsigned i;
+
+	if (n == 0)
+		return 0;
+
+	for (i = 0; i < n; i++) {
+		t->tm_mon++;
+		if (mktime(t) == -1) {
+			t->tm_mon = 0;
+			if (sub_inc_year(t, 1) == -1)
+				return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int sub_inc_day(struct tm *t, int n)
+{
+	unsigned i;
+
+	if (n == 0)
+		return 0;
+
+	for (i = 0; i < n; i++) {
+		t->tm_mday++;
+		if (mktime(t) == -1) {
+			t->tm_mday = 1;
+			if (sub_inc_month(t, 1) == -1)
+				return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int sub_inc_hour(struct tm *t, int n)
+{
+	unsigned i;
+
+	if (n == 0)
+		return 0;
+
+	for (i = 0; i < n; i++) {
+		t->tm_hour++;
+		if (mktime(t) == -1) {
+			t->tm_hour = 0;
+			if (sub_inc_day(t, 1) == -1)
+				return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int sub_inc_minute(struct tm *t, int n)
+{
+	unsigned i;
+
+	if (n == 0)
+		return 0;
+
+	for (i = 0; i < n; i++) {
+		t->tm_min++;
+		if (mktime(t) == -1) {
+			t->tm_min = 0;
+			if (sub_inc_hour(t, 1) == -1)
+				return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int sub_inc_second(struct tm *t, int n)
+{
+	time_t r;
+	struct tm *tmp;
+
+	if (n == 0)
+		return 0;
+
+	r = mktime(t);
+
+	if (r + n <= r)
+		return -1;
+	r += n;
+
+	tmp = localtime(&r);
+	*t = *tmp;
+
+	return 0;
+}
+
+/* super inefficient, but should best-possible avoid any weird leap
+ * years/seconds/dst-problems/other future changes */
+bool entry_is_active(struct entry_s *e, time_t now)
+{
+	struct tm t, *tmp;
+	time_t rtmp, now_plus_warn;
+	
+	assert(e != NULL);
+
+	tmp = localtime(&now);
+	assert(tmp != NULL);
+	t = *tmp;
+
+	if (sub_inc_year(&t, e->warn.year))
+		return false;
+	if (sub_inc_month(&t, e->warn.month))
+		return false;
+	if (sub_inc_day(&t, e->warn.day))
+		return false;
+	if (sub_inc_hour(&t, e->warn.hour))
+		return false;
+	if (sub_inc_minute(&t, e->warn.minute))
+		return false;
+	if (sub_inc_second(&t, e->warn.second))
+		return false;
+
+	now_plus_warn = mktime(&t);
+
+	if (e->type == ENTRY_TYPE_ON) {
+		if (e->start >= now && e->start <= now_plus_warn)
+			return true;
+
+		return false;
+	}
+
+	tmp = localtime(&(e->start));
+	assert(tmp != NULL);
+	t = *tmp;
+
+	if (e->has_end && now > e->end)
+		return false;
+
+	for (rtmp = e->start;;) {
+		rtmp = mktime(&t);
+
+		if (rtmp > now_plus_warn)
+			return false;
+
+		if (rtmp >= now)
+			return true;
+
+		if (sub_inc_year(&t, e->every.year))
+			return false;
+		if (sub_inc_month(&t, e->every.month))
+			return false;
+		if (sub_inc_day(&t, e->every.day))
+			return false;
+		if (sub_inc_hour(&t, e->every.hour))
+			return false;
+		if (sub_inc_minute(&t, e->every.minute))
+			return false;
+		if (sub_inc_second(&t, e->every.second))
+			return false;
+	}
+}
diff --git a/src/entry.h b/src/entry.h
new file mode 100644
index 0000000..1420d9b
--- /dev/null
+++ b/src/entry.h
@@ -0,0 +1,27 @@
+#ifndef EVERY_ENTRY_H
+#define EVERY_ENTRY_H
+
+#include <time.h>
+#include <stdbool.h>
+
+enum entry_type_e {
+	ENTRY_TYPE_ON,
+	ENTRY_TYPE_EVERY,
+};
+
+struct entry_interval_s {
+	int year, month, day, hour, minute, second;
+};
+
+/* type ON uses only start and warn */
+struct entry_s {
+	enum entry_type_e type;
+	bool has_end;
+	time_t start, end;
+	struct entry_interval_s every, warn;
+};
+
+/* test if an entry needs warning */
+bool entry_is_active(struct entry_s *e, time_t now);
+
+#endif
diff --git a/src/opt.c b/src/opt.c
index eebb248..31b1186 100644
--- a/src/opt.c
+++ b/src/opt.c
@@ -14,7 +14,7 @@ static struct simple_opt options[] = {
 	{ SIMPLE_OPT_FLAG, 'v', "version", false,
 		"print the version of every in use and exit" },
 	{ SIMPLE_OPT_STRING, 'c', "calendar", true,
-		"path to calendar", "<file>" },
+		"path to calendar file", "<file>" },
 	{ SIMPLE_OPT_STRING, 'e', "editor", true,
 		"text editor for editing calendars", "<cmd>" },
 	{ SIMPLE_OPT_END }
@@ -35,7 +35,7 @@ void opt_parse(int argc, char **argv)
 	/* help */
 	if (options[0].was_seen) {
 		simple_opt_print_usage(stdout, 80, argv[0],
-			"[-c CALENDAR_FILE] [-m OUTPUT_MODE]",
+			"[-c CALENDAR_FILE] [-e TEXT_EDITOR] [COMMAND]",
 			"every is a flexible, console-based event calendar",
 			options);