refactor: enhance schedule and document handling in schemas

- Simplify schedule expiration logic in CronService by removing unnecessary date checks.
- Improve error handling in DocumentSchema for document page retrieval, ensuring graceful failure.
- Add validation in ScheduleSchema to restrict schedule retrieval to authorized centers and prevent subscription-based access.
- Implement checks to reject schedules with start dates in the past or today, enhancing data integrity.

src/Schedule/schedule.schema.ts

@@ -220,10 +220,32 @@ export class ScheduleSchema extends PothosSchema {
         type: this.schedule(),
         description: 'Retrieve a single schedule by its unique identifier.',
         args: this.builder.generator.findUniqueArgs('Schedule'),
-        resolve: async (query, _root, args, _ctx, _info) => {
+        resolve: async (query, _root, args, ctx, _info) => {
+          if (ctx.isSubscription) {
+            throw new Error('Cannot retrieve schedule in subscription')
+          }
+          if (!ctx.http?.me?.id) {
+            throw new Error('User not found')
+          }
+          // only return schedule belong to center
+          const center = await this.prisma.center.findFirst({
+            where: {
+              centerMentors: {
+                some: {
+                  mentorId: ctx.http.me.id,
+                },
+              },
+            },
+          })
+          if (!center) {
+            throw new Error('Center not found')
+          }
           return await this.prisma.schedule.findUnique({
             ...query,
-            where: args.where,
+            where: {
+              id: args.where?.id,
+              managedService: { service: { centerId: center.id } },
+            },
           })
         },
       }),
@@ -300,6 +322,10 @@ d72a864e-2f41-45ab-9c9b-bf0512a31883,e9be51fd-2382-4e43-9988-74e76fde4b56,2024-1
             throw new Error('Cannot create schedule in subscription')
           }
           Logger.log('args.schedule', args.schedule)
+          // reject schedule if start date is today or in the past
+          if (DateTimeUtils.fromDate(args.schedule.scheduleStart as Date).day <= DateTimeUtils.now().day) {
+            throw new Error('Start date is in the past or today')
+          }
           // generate preview and check if there is any overlapping with other schedules date in same service
           const previewSchedule = await this.scheduleService.createSchedulePreviewForCenter({
             startDate: args.schedule.scheduleStart as string,