feat: Custom schedule rules

scheduleRules.js

@@ -0,0 +1,43 @@
+// Rules: start and end in 24h format, interval in minutes
+const scheduleRules = [
+  { start: "0:00",  end: "3:00",  interval: 180 },
+  { start: "3:00",  end: "4:00",  interval: 60 },
+  { start: "5:00",  end: "6:00",  interval: 30 },
+  { start: "6:00",  end: "7:30",  interval: 15 },
+  { start: "7:30",  end: "16:00", interval: 5 },
+  { start: "16:00", end: "19:00", interval: 60 },
+  { start: "19:00", end: "0:00",  interval: 180 }
+];
+
+function toMinutes(timeStr) {
+  const [h, m] = timeStr.split(":").map(Number);
+  return h * 60 + (m || 0);
+}
+
+function getCurrentInterval(date = new Date()) {
+  const nowMinutes = date.getHours() * 60 + date.getMinutes();
+
+  for (const rule of scheduleRules) {
+    let startMin = toMinutes(rule.start);
+    let endMin   = toMinutes(rule.end === "0:00" ? "24:00" : rule.end);
+
+    // Handle wrap-around midnight
+    if (endMin <= startMin) {
+      if (nowMinutes >= startMin || nowMinutes < endMin) {
+        return rule.interval;
+      }
+    } else {
+      if (nowMinutes >= startMin && nowMinutes < endMin) {
+        return rule.interval;
+      }
+    }
+  }
+
+  return null;
+}
+
+module.exports = {
+  scheduleRules,
+  getCurrentInterval,
+  toMinutes
+};