Saved ExamSchedule to local storage, move some function to utils.ts.

app/page.tsx

@@ -3,6 +3,11 @@
 import { useState, useEffect, FC } from "react";
 import EditDialog from "@/components/editDialog";
 import { Exam, Attendance, EditingData } from "@/lib/interfaces";
+import {
+  saveExamScheduleToLocalStorage,
+  loadExamScheduleFromLocalStorage,
+  calculateRemainingTime
+} from "@/lib/utils";
 
 const Home: FC = () => {
   const [isDialogOpen, setIsDialogOpen] = useState<boolean>(false);
@@ -68,6 +73,17 @@ const Home: FC = () => {
     setIsDialogOpen(false);
   };
 
+  useEffect(() => {
+    const savedSchedule = loadExamScheduleFromLocalStorage();
+    if (savedSchedule.length > 0) {
+      setExamSchedule(savedSchedule);
+    }
+  }, []);
+
+  useEffect(() => {
+    saveExamScheduleToLocalStorage(examSchedule);
+  }, [examSchedule]);
+
   useEffect(() => {
     const intervalId = setInterval(() => {
       setCurrentTime(new Date());
@@ -92,15 +108,6 @@ const Home: FC = () => {
     setCurrentExam(current ?? null);
   }, [currentTime, examSchedule]);
 
-  const calculateRemainingTime = (endTime: string): number => {
-    const now = new Date();
-    const end = new Date(now.toDateString() + " " + endTime);
-    const remainingMinutes = Math.floor(
-      (end.getTime() - now.getTime()) / 60000,
-    );
-    return remainingMinutes >= 0 ? remainingMinutes : 0;
-  };
-
   return (
     <>
       <div className="absolute top-0 left-0 p-2 text-xs text-gray-400 font-bold">

lib/utils.ts

@@ -0,0 +1,17 @@
+import { Exam } from "@lib/interfaces";
+
+export const saveExamScheduleToLocalStorage = (schedule: Exam[]) => {
+    localStorage.setItem('examSchedule', JSON.stringify(schedule));
+};
+
+export const loadExamScheduleFromLocalStorage = () => {
+    const schedule = localStorage.getItem('examSchedule');
+    return schedule ? JSON.parse(schedule) : [];
+};
+
+export const calculateRemainingTime = (endTime: string) => {
+    const now = new Date();
+    const end = new Date(now.toDateString() + " " + endTime);
+    const remainingMinutes = Math.floor((end.getTime() - now.getTime()) / 60000);
+    return remainingMinutes >= 0 ? remainingMinutes : 0;
+};