import { differenceInCalendarDays, format, isWeekend } from "date-fns";
import { TerminStatus, TerminType, UserRole } from "@prisma/client";

import { getDailyAbsences } from "@/actions/absences";
import { requireRole } from "@/lib/auth-utils";
import { prisma } from "@/lib/prisma";
import { AbsencesClient } from "./_components/absences-client";
import { type AbsenceTableItem } from "./absence-table";

export const metadata = { title: "Abwesenheiten · Kita-Planer" };

export default async function AdminAbwesenheitenPage({
  searchParams,
}: {
  searchParams: Promise<{ date?: string }>;
}) {
  const session = await requireRole([
    UserRole.ADMIN,
    UserRole.KOORDINATOR,
    UserRole.ERZIEHER,
  ]);
  const resolvedSearchParams = await searchParams;
  const kitaId = session.user.kitaId!;
  const today = startOfLocalDay(new Date());
  const selectedDate = parseDateParam(resolvedSearchParams.date, today);
  const dateKey = format(selectedDate, "yyyy-MM-dd");
  const result = await getDailyAbsences({ date: dateKey });
  const absences = result.absences ?? [];
  const childCount = await prisma.child.count({
    where: { kitaId, active: true },
  });
  const upcomingAbsenceCount = await prisma.absence.count({
    where: {
      kitaId,
      startDate: { gt: selectedDate },
    },
  });
  const closure = await prisma.termin.findFirst({
    where: {
      kitaId,
      status: TerminStatus.CONFIRMED,
      type: { in: [TerminType.SCHLIESSTAG, TerminType.TEAMTAG] },
      startDate: { lte: selectedDate },
      endDate: { gte: selectedDate },
    },
    select: { title: true, type: true },
    orderBy: { startDate: "asc" },
  });
  const isToday = dateKey === format(today, "yyyy-MM-dd");
  const isTooFarFuture = differenceInCalendarDays(selectedDate, today) > 30;
  const isClosedDay = isWeekend(selectedDate) || !!closure;
  const tableItems: AbsenceTableItem[] = absences.map((absence) => ({
    id: absence.id,
    childName: absence.childName,
    familyName: absence.familyName,
    reason: absence.reason,
    note: absence.note,
    startDate: absence.startDate,
    endDate: absence.endDate,
  }));

  return (
    <div className="mx-auto max-w-[1280px] px-11 py-9 pb-16 max-[760px]:px-5">
      <AbsencesClient
        initialAbsences={tableItems}
        childCount={childCount}
        upcomingAbsenceCount={upcomingAbsenceCount}
        closure={closure}
        dateKey={dateKey}
        selectedDateStr={selectedDate.toISOString()}
        isToday={isToday}
        isTooFarFuture={isTooFarFuture}
        isClosedDay={isClosedDay}
        todayStr={today.toISOString()}
        error={result.error ?? null}
      />
    </div>
  );
}

function parseDateParam(value: string | undefined, fallback: Date) {
  if (!value) return fallback;
  const parsed = new Date(`${value}T00:00:00`);
  return Number.isNaN(parsed.getTime()) ? fallback : parsed;
}

function startOfLocalDay(date: Date) {
  const nextDate = new Date(date);
  nextDate.setHours(0, 0, 0, 0);
  return nextDate;
}