added timers to auto-hide help and for counting the time it took to solve the puzzle

timer.c

@@ -0,0 +1,44 @@
+#include "timer.h"
+
+struct timeval start_time;
+
+double get_time() {
+  struct timeval current_time;
+  gettimeofday(&current_time, NULL);
+
+  return (double)(current_time.tv_sec - start_time.tv_sec) + (double)(current_time.tv_usec - start_time.tv_usec) / 1000000.0;
+}
+
+void start_internal_timer() {
+  gettimeofday(&start_time, NULL);
+}
+
+bool timer_ended(Timer *timer) {
+  if (!timer->is_running) return false;
+
+  return get_time() - timer->time >= timer->duration;
+}
+
+void timer_start(Timer *timer, float duration) {
+  timer->time = get_time();
+  timer->duration = duration;
+  timer->is_running = true;
+}
+
+void timer_reset(Timer *timer) {
+  timer->time = get_time();
+  timer->is_running = true;
+}
+
+float timer_remaining(Timer *timer) {
+  return timer->duration - (get_time() - timer->time);
+}
+
+void timer_stop(Timer *timer) {
+  timer->time = 0.0f;
+  timer->is_running = false;
+}
+
+float timer_elapsed(Timer *timer) {
+  return get_time() - timer->time;
+}