Fix absences and appointments to block proper slots

src/lib/server/services/__tests__/schedule-service.test.ts

@@ -148,6 +148,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -248,6 +249,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -270,6 +272,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -284,6 +287,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-03T23:59:59.999Z", // 3 days
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -316,6 +320,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z", // Monday
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -388,6 +393,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -463,6 +469,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z", // Monday
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -572,6 +579,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -645,6 +653,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 
@@ -729,6 +738,7 @@ describe("ScheduleService", () => {
       const validRequest: ScheduleRequest = {
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-01T23:59:59.999Z",
+        timeZone: "Europe/Berlin",
         tenantId: mockTenantId,
       };
 

src/lib/server/services/schedule-service.ts

@@ -12,11 +12,16 @@ import { eq, and, between, sql, or, inArray } from "drizzle-orm";
 import logger from "$lib/logger";
 import { z } from "zod";
 import { ValidationError } from "../utils/errors";
+import { isValidTimeZone, toLocalTime, toLocalTimeIgnoringDst } from "../utils/timezone";
 
 const scheduleRequestSchema = z.object({
   startDate: z.string().datetime({ offset: true }), // ISO date string with timezone
   endDate: z.string().datetime({ offset: true }), // ISO date string with timezone
   tenantId: z.string().uuid({ message: "Invalid tenant ID format" }),
+  timeZone: z
+    .string()
+    .refine((tz) => isValidTimeZone(tz), { message: "Invalid IANA timezone format" })
+    .default("UTC"),
   channelId: z.string().uuid({ message: "Invalid channel ID format" }).optional(),
   agentId: z.string().uuid({ message: "Invalid agent ID format" }).optional(),
   staffUserId: z.string().uuid({ message: "Invalid staff user ID format" }).optional(),
@@ -217,6 +222,7 @@ export class ScheduleService {
         absences,
         channelAgents,
         staffKeyShares,
+        timeZone: request.timeZone,
       });
 
       log.debug("Schedule generated successfully", {
@@ -252,6 +258,7 @@ export class ScheduleService {
     absences,
     channelAgents,
     staffKeyShares,
+    timeZone,
   }: {
     startDate: Date;
     endDate: Date;
@@ -261,6 +268,7 @@ export class ScheduleService {
     absences: SelectAgentAbsence[];
     channelAgents: { channelId: string; agent: SelectAgent }[];
     staffKeyShares: Record<string, string>;
+    timeZone: string;
   }): Promise<DaySchedule[]> {
     const dailySchedules: DaySchedule[] = [];
 
@@ -316,6 +324,7 @@ export class ScheduleService {
           appointments: dayAppointments,
           agents: channelAgentsList,
           absences,
+          timeZone,
         });
 
         daySchedule.channels[channel.id] = {
@@ -343,12 +352,14 @@ export class ScheduleService {
     appointments,
     agents,
     absences,
+    timeZone,
   }: {
     date: Date;
     slotTemplates: SelectSlotTemplate[];
     appointments: SelectAppointment[];
     agents: SelectAgent[];
     absences: SelectAgentAbsence[];
+    timeZone: string;
   }): TimeSlot[] {
     const availableSlots: TimeSlot[] = [];
 
@@ -393,7 +404,9 @@ export class ScheduleService {
         );
 
         const availableAgents = agents.filter((agent) => {
-          if (this.isAgentAbsent(agent.id, slotStartDateTime, slotEndDateTime, absences)) {
+          if (
+            this.isAgentAbsent(agent.id, slotStartDateTime, slotEndDateTime, absences, timeZone)
+          ) {
             return false;
           }
 
@@ -402,6 +415,7 @@ export class ScheduleService {
             slotStartDateTime,
             slotEndDateTime,
             appointments,
+            timeZone,
           );
         });
 
@@ -430,19 +444,21 @@ export class ScheduleService {
     slotStartDateTime: Date,
     slotEndDateTime: Date,
     absences: SelectAgentAbsence[],
+    timeZone: string,
   ): boolean {
     return absences.some((absence) => {
       if (absence.agentId !== agentId) return false;
 
-      const absenceStart = new Date(absence.startDate);
-      const absenceEnd = new Date(absence.endDate);
+      const absenceStart = toLocalTime(new Date(absence.startDate), timeZone);
+      const absenceEnd = toLocalTime(new Date(absence.endDate), timeZone);
+      const slotStart = toLocalTimeIgnoringDst(slotStartDateTime, timeZone);
+      const slotEnd = toLocalTimeIgnoringDst(slotEndDateTime, timeZone);
 
       // For time-specific absences, check if the time slot overlaps
-      return (
-        (slotStartDateTime >= absenceStart && slotStartDateTime < absenceEnd) ||
-        (slotEndDateTime > absenceStart && slotEndDateTime <= absenceEnd) ||
-        (slotStartDateTime <= absenceStart && slotEndDateTime >= absenceEnd)
-      );
+      const slotStartsDuringAbsence = slotStart >= absenceStart && slotStart < absenceEnd;
+      const slotEndsDuringAbsence = slotEnd > absenceStart && slotEnd <= absenceEnd;
+      const slotCoversEntireAbsence = slotStart <= absenceStart && slotEnd >= absenceEnd;
+      return slotStartsDuringAbsence || slotEndsDuringAbsence || slotCoversEntireAbsence;
     });
   }
 
@@ -454,6 +470,7 @@ export class ScheduleService {
     slotStartDateTime: Date,
     slotEndDateTime: Date,
     appointments: SelectAppointment[],
+    timeZone: string,
   ): boolean {
     return appointments.some((appointment) => {
       if (appointment.agentId !== agentId) return false;
@@ -461,8 +478,13 @@ export class ScheduleService {
       const appointmentStart = new Date(appointment.appointmentDate);
       const appointmentDuration = Number.isFinite(appointment.duration) ? appointment.duration : 0;
       const appointmentEnd = new Date(appointmentStart.getTime() + appointmentDuration * 60 * 1000);
+      const slotStart = toLocalTimeIgnoringDst(slotStartDateTime, timeZone);
+      const slotEnd = toLocalTimeIgnoringDst(slotEndDateTime, timeZone);
 
-      return slotStartDateTime < appointmentEnd && slotEndDateTime > appointmentStart;
+      return (
+        slotStart < toLocalTime(appointmentEnd, timeZone) &&
+        slotEnd > toLocalTime(appointmentStart, timeZone)
+      );
     });
   }
 

src/lib/server/utils/timezone.ts

@@ -0,0 +1,30 @@
+export function isValidTimeZone(timeZone: string): boolean {
+  if (timeZone === "UTC" || timeZone === "Etc/UTC") {
+    return true;
+  }
+
+  const supportedValuesOf = (Intl as unknown as { supportedValuesOf?: (key: string) => string[] })
+    .supportedValuesOf;
+  if (supportedValuesOf) {
+    return supportedValuesOf("timeZone").includes(timeZone);
+  }
+
+  // Conservative fallback when Intl.supportedValuesOf is unavailable.
+  return timeZone === "UTC" || /^[A-Za-z_]+\/[A-Za-z_]+(?:\/[A-Za-z_]+)?$/.test(timeZone);
+}
+
+export function toLocalTime(utcDate: Date, timeZone: string): Date {
+  const utcStr = utcDate.toLocaleString("en-US", { timeZone: "UTC" });
+  const tzStr = utcDate.toLocaleString("en-US", { timeZone });
+  const offsetMs = new Date(tzStr).getTime() - new Date(utcStr).getTime();
+  return new Date(utcDate.getTime() + offsetMs);
+}
+
+export function toLocalTimeIgnoringDst(utcDate: Date, timeZone: string): Date {
+  // Use January 1st to get the standard (non-DST) offset for this timezone
+  const jan = new Date(utcDate.getFullYear(), 0, 1);
+  const utcStr = jan.toLocaleString("en-US", { timeZone: "UTC" });
+  const tzStr = jan.toLocaleString("en-US", { timeZone });
+  const standardOffsetMs = new Date(tzStr).getTime() - new Date(utcStr).getTime();
+  return new Date(utcDate.getTime() + standardOffsetMs);
+}

src/routes/(pages)/(clients)/book-appointment/[[id]]/(components)/select-slot.svelte

@@ -9,6 +9,11 @@
   import { Text } from "$lib/components/ui/typography";
   import { publicStore } from "$lib/stores/public.js";
   import type { TPublicAppointment, TPublicSchedule, TPublicSlot } from "$lib/types/public.js";
+  import {
+    localToUTC,
+    timeUTCToLocalWithoutOffset,
+    utcToLocalWithoutDST,
+  } from "$lib/utils/datetime";
   import {
     CalendarDate,
     fromDate,
@@ -23,11 +28,6 @@
   import type { DateMatcher } from "bits-ui";
   import type { OnChangeFn } from "vaul-svelte";
   import { fetchSchedule } from "./utils";
-  import {
-    localToUTC,
-    timeUTCToLocalWithoutOffset,
-    utcToLocalWithoutDST,
-  } from "$lib/utils/datetime";
 
   const {
     channel,
@@ -113,18 +113,8 @@
       curDateStr === dateStr
         ? slots.filter((slot) => {
             if (dateStr === curDateStr) {
-              const now = new Date();
-              const slotDate = new Date(slot.from);
-              const slotTime = new Date(
-                date.year,
-                date.month - 1,
-                date.day,
-                slotDate.getHours(),
-                slotDate.getMinutes(),
-                0,
-                0,
-              );
-              return slotTime > now;
+              // double check, when be changed
+              return utcToLocalWithoutDST(new Date(slot.from)) > new Date();
             }
             return true;
           })
@@ -240,9 +230,10 @@
                 {m["public.steps.slot.selectTime"]()}
               </Text>
               {#each slots as slot (slot.from)}
-                <Button onclick={() => selectSlot(slot)} class="w-full"
-                  >{formatSlotTime(slot)}</Button
-                >
+                <Button onclick={() => selectSlot(slot)} class="w-full">
+                  {formatSlotTime(slot)}
+                  {slot.from}
+                </Button>
               {/each}
             </div>
           </ScrollArea>

src/routes/(pages)/(clients)/book-appointment/[[id]]/(components)/utils.ts

@@ -112,6 +112,7 @@ export const fetchSchedule = async (opts: {
   const params = new URLSearchParams({
     startDate: startDate.toISOString(),
     endDate: endDate.toISOString(),
+    timeZone: getLocalTimeZone().toString(),
     channel: opts.channel,
     agent: opts.agent || "",
   });

src/routes/(pages)/dashboard/calendar/(components)/SlotPreview.svelte

@@ -27,7 +27,8 @@
   variant="ghost"
   onclick={setCalendarItem}
 >
-  <span class="sr-only">
+  <span class="">
+    {item.start}
     {m["calendar.addAppointment.preview"]({
       time: toDisplayDateTime(utcToLocalWithoutDST(new Date(item.start)), {
         hour: "2-digit",

src/routes/(pages)/dashboard/calendar/(components)/utils.ts

@@ -7,7 +7,7 @@ import { calendarStore } from "$lib/stores/calendar";
 import { staffCrypto } from "$lib/stores/staff-crypto";
 import type { TCalendar, TCalendarItem } from "$lib/types/calendar";
 import { localToUTCWithoutDST } from "$lib/utils/datetime";
-import type { CalendarDate } from "@internationalized/date";
+import { getLocalTimeZone, type CalendarDate } from "@internationalized/date";
 import { get } from "svelte/store";
 
 export const fetchCalendar = async (opts: { tenant: string; startDate: CalendarDate }) => {
@@ -23,6 +23,7 @@ export const fetchCalendar = async (opts: { tenant: string; startDate: CalendarD
   const params = new URLSearchParams({
     startDate: localStartDate.toISOString(),
     endDate: localEndDate.toISOString(),
+    timeZone: getLocalTimeZone().toString(),
   });
   await auth.waitForRefresh();
   const res = await fetch(`/api/tenants/${opts.tenant}/calendar?${params}`, {

src/routes/(pages)/dashboard/calendar/+page.svelte

@@ -13,6 +13,7 @@
   import { channels as channelsStore } from "$lib/stores/channels";
   import { sidebar } from "$lib/stores/sidebar";
   import type { TAppointmentFilter, TCalendar, TCalendarItem } from "$lib/types/calendar";
+  import { timeUTCToLocalWithoutOffset, utcToLocalWithoutDST } from "$lib/utils/datetime";
   import { getCurrentTranlslation } from "$lib/utils/localizations";
   import {
     getLocalTimeZone,
@@ -29,7 +30,6 @@
   import CalendarFilters from "./(components)/CalendarFilters.svelte";
   import CalendarHeader from "./(components)/CalendarHeader.svelte";
   import { fetchCalendar, openAppointmentById } from "./(components)/utils";
-  import { timeUTCToLocalWithoutOffset, utcToLocalWithoutDST } from "$lib/utils/datetime";
 
   const convertDate = (dateStr: string) => {
     const zonedDateTime = parseAbsoluteToLocal(dateStr);
@@ -136,7 +136,8 @@
       if (["all", "available"].includes(shownAppointments)) {
         if (shownChannels.length === 0 || shownChannels.includes(channelId)) {
           channelData.availableSlots.forEach((slot) => {
-            if (utcToLocalWithoutDST(new Date(slot.to)) > new Date()) {
+            const isSlotInPast = utcToLocalWithoutDST(new Date(slot.to)) < new Date();
+            if (!isSlotInPast) {
               if (
                 shownAgents.length === 0 ||
                 shownAgents.some((id) => slot.availableAgents.map((a) => a.id).includes(id))

src/routes/api/tenants/[id]/calendar/+server.ts

@@ -33,6 +33,14 @@ registerOpenAPIRoute("/tenants/{id}/calendar", "GET", {
       schema: { type: "string", format: "date-time" },
       description: "End date for the calendar range (ISO 8601 format with timezone)",
     },
+    {
+      name: "timeZone",
+      in: "query",
+      required: false,
+      schema: { type: "string" },
+      description:
+        "IANA timezone name for schedule calculations (e.g., 'Europe/Berlin', 'America/New_York'). Defaults to 'UTC' if not provided. This ensures slots are calculated with the correct daylight saving time offset.",
+    },
   ],
   responses: {
     "200": {
@@ -124,6 +132,7 @@ export const GET: RequestHandler = async ({ params, url, locals }) => {
     // Parse query parameters for date range
     const startDateParam = url.searchParams.get("startDate");
     const endDateParam = url.searchParams.get("endDate");
+    const timeZoneParam = url.searchParams.get("timeZone") || "UTC";
 
     if (!startDateParam || !endDateParam) {
       throw new ValidationError("Both startDate and endDate query parameters are required");
@@ -153,6 +162,7 @@ export const GET: RequestHandler = async ({ params, url, locals }) => {
       tenantId,
       startDate: startDate.toISOString(),
       endDate: endDate.toISOString(),
+      timeZone: timeZoneParam,
     });
 
     const scheduleService = await ScheduleService.forTenant(tenantId);
@@ -164,6 +174,7 @@ export const GET: RequestHandler = async ({ params, url, locals }) => {
       tenantId,
       startDate: startDateParam,
       endDate: endDateParam,
+      timeZone: timeZoneParam,
       staffUserId,
     });
 

src/routes/api/tenants/[id]/calendar/__tests__/calendar-api.test.ts

@@ -142,6 +142,7 @@ describe("Calendar API", () => {
         tenantId: "tenant-123",
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-02T00:00:00.000Z",
+        timeZone: "UTC",
         staffUserId: undefined,
       });
     });

src/routes/api/tenants/[id]/schedule/+server.ts

@@ -138,6 +138,7 @@ export const GET: RequestHandler = async ({ params, url }) => {
     // Parse query parameters for date range
     const startDateParam = url.searchParams.get("startDate");
     const endDateParam = url.searchParams.get("endDate");
+    const timeZoneParam = url.searchParams.get("timeZone") || "UTC";
     const channelIdParam = url.searchParams.get("channel");
     const agentIdParam = url.searchParams.get("agent");
 
@@ -169,6 +170,7 @@ export const GET: RequestHandler = async ({ params, url }) => {
       tenantId,
       startDate: startDate.toISOString(),
       endDate: endDate.toISOString(),
+      timeZone: timeZoneParam,
     });
 
     const scheduleService = await ScheduleService.forTenant(tenantId);
@@ -178,6 +180,7 @@ export const GET: RequestHandler = async ({ params, url }) => {
       endDate: endDateParam,
       channelId: channelIdParam || undefined,
       agentId: agentIdParam || undefined,
+      timeZone: timeZoneParam,
     });
 
     // Transform schedule to client-friendly format (remove appointments, simplify available slots)

src/routes/api/tenants/[id]/schedule/__tests__/schedule-api.test.ts

@@ -126,6 +126,7 @@ describe("Schedule API Route", () => {
         tenantId: mockTenantId,
         startDate: "2024-01-01T00:00:00.000Z",
         endDate: "2024-01-07T23:59:59.999Z",
+        timeZone: "UTC",
       });
     });
 
@@ -305,6 +306,7 @@ describe("Schedule API Route", () => {
         tenantId: mockTenantId,
         startDate,
         endDate,
+        timeZone: "UTC",
       });
     });
   });