feat(api): explain holiday-aware vacation deductions

packages/api/src/router/vacation-read.ts

@@ -5,12 +5,12 @@ import { findUniqueOrThrow } from "../db/helpers.js";
 import { RESOURCE_BRIEF_SELECT } from "../db/selects.js";
 import { anonymizeResource, anonymizeUser, getAnonymizationDirectory } from "../lib/anonymization.js";
 import { loadResourceHolidayContext } from "../lib/resource-holiday-context.js";
-import {
-  VACATION_BALANCE_TYPES,
-  type VacationChargeableInput,
-} from "../lib/vacation-deduction-snapshot.js";
-import { countCalendarDaysInPeriod, countVacationChargeableDays } from "../lib/vacation-day-count.js";
 import { protectedProcedure, type TRPCContext } from "../trpc.js";
+import {
+  buildVacationPreview,
+  findVacationResourceChapter,
+  listChapterVacationOverlaps,
+} from "./vacation-read-support.js";
 
 type VacationReadContext = Pick<TRPCContext, "db" | "dbUser">;
 
@@ -138,53 +138,13 @@ export const vacationReadProcedures = {
         input.startDate,
         input.endDate,
       );
-      const vacation: Pick<VacationChargeableInput, "startDate" | "endDate" | "isHalfDay"> = {
+      return buildVacationPreview({
+        type: input.type,
         startDate: input.startDate,
         endDate: input.endDate,
         isHalfDay: input.isHalfDay ?? false,
-      };
-      const requestedDays = countCalendarDaysInPeriod(vacation);
-      const effectiveDays = VACATION_BALANCE_TYPES.has(input.type)
-        ? countVacationChargeableDays({
-          vacation,
-          countryCode: holidayContext.countryCode,
-          federalState: holidayContext.federalState,
-          metroCityName: holidayContext.metroCityName,
-          calendarHolidayStrings: holidayContext.calendarHolidayStrings,
-          publicHolidayStrings: holidayContext.publicHolidayStrings,
-        })
-        : requestedDays;
-      const publicHolidayDates = [...new Set([
-        ...holidayContext.calendarHolidayStrings,
-        ...holidayContext.publicHolidayStrings,
-      ])].sort();
-      const holidayDetails = publicHolidayDates.map((date) => ({
-        date,
-        source:
-          holidayContext.calendarHolidayStrings.includes(date) && holidayContext.publicHolidayStrings.includes(date)
-            ? "CALENDAR_AND_LEGACY"
-            : holidayContext.calendarHolidayStrings.includes(date)
-              ? "CALENDAR"
-              : "LEGACY_PUBLIC_HOLIDAY",
-      }));
-
-      return {
-        requestedDays,
-        effectiveDays,
-        deductedDays: VACATION_BALANCE_TYPES.has(input.type) ? effectiveDays : 0,
-        publicHolidayDates,
-        holidayDetails,
-        holidayContext: {
-          countryCode: holidayContext.countryCode ?? null,
-          countryName: holidayContext.countryName ?? null,
-          federalState: holidayContext.federalState ?? null,
-          metroCityName: holidayContext.metroCityName ?? null,
-          sources: {
-            hasCalendarHolidays: holidayContext.calendarHolidayStrings.length > 0,
-            hasLegacyPublicHolidayEntries: holidayContext.publicHolidayStrings.length > 0,
-          },
-        },
-      };
+        holidayContext,
+      });
     }),
 
   list: protectedProcedure
@@ -316,27 +276,16 @@ export const vacationReadProcedures = {
     .query(async ({ ctx, input }) => {
       await assertCanReadVacationResource(ctx, input.resourceId);
 
-      const resource = await ctx.db.resource.findUnique({
-        where: { id: input.resourceId },
-        select: { chapter: true },
-      });
-      if (!resource?.chapter) {
+      const chapter = await findVacationResourceChapter(ctx.db, input.resourceId);
+      if (!chapter) {
         return [];
       }
 
-      return ctx.db.vacation.findMany({
-        where: {
-          resource: { chapter: resource.chapter },
-          resourceId: { not: input.resourceId },
-          status: { in: [VacationStatus.APPROVED, VacationStatus.PENDING] },
-          startDate: { lte: input.endDate },
-          endDate: { gte: input.startDate },
-        },
-        include: {
-          resource: { select: RESOURCE_BRIEF_SELECT },
-        },
-        orderBy: { startDate: "asc" },
-        take: 20,
+      return listChapterVacationOverlaps(ctx.db, {
+        chapter,
+        resourceId: input.resourceId,
+        startDate: input.startDate,
+        endDate: input.endDate,
       });
     }),
 
@@ -372,19 +321,11 @@ export const vacationReadProcedures = {
         });
       }
 
-      const overlaps = await ctx.db.vacation.findMany({
-        where: {
-          resource: { chapter: resource.chapter },
-          resourceId: { not: input.resourceId },
-          status: { in: [VacationStatus.APPROVED, VacationStatus.PENDING] },
-          startDate: { lte: input.endDate },
-          endDate: { gte: input.startDate },
-        },
-        include: {
-          resource: { select: RESOURCE_BRIEF_SELECT },
-        },
-        orderBy: { startDate: "asc" },
-        take: 20,
+      const overlaps = await listChapterVacationOverlaps(ctx.db, {
+        chapter: resource.chapter,
+        resourceId: input.resourceId,
+        startDate: input.startDate,
+        endDate: input.endDate,
       });
 
       return mapTeamOverlapDetail({