import type { NotdienstAlarm } from "@prisma/client";
import {
  addDays,
  dateSchema,
  dateKey,
  todayKey,
  minuteClock,
} from "@/lib/staff/calculations";

export { dateKey, todayKey };
const berlin = new Intl.DateTimeFormat("en-CA", {
  timeZone: "Europe/Berlin",
  year: "numeric",
  month: "2-digit",
  day: "2-digit",
  hour: "2-digit",
  minute: "2-digit",
  hourCycle: "h23",
});
export function berlinInstant(date: string, minute: number) {
  dateSchema.parse(date);
  const target = new Date(`${date}T00:00:00Z`).getTime() + minute * 60_000;
  let value = target;
  for (let i = 0; i < 3; i++) {
    const parts = Object.fromEntries(
      berlin.formatToParts(new Date(value)).map((p) => [p.type, p.value]),
    );
    const represented = Date.parse(
      `${parts.year}-${parts.month}-${parts.day}T${parts.hour}:${parts.minute}:00Z`,
    );
    const diff = target - represented;
    if (!diff) return new Date(value);
    value += diff;
  }
  throw new Error(
    "Diese Uhrzeit existiert wegen der Zeitumstellung nicht. Bitte eine andere Uhrzeit wählen.",
  );
}
export function endOfAlarm(
  date: string,
  wholeDay: boolean,
  endMinute?: number | null,
) {
  return wholeDay
    ? berlinInstant(addDays(date, 1), 0)
    : berlinInstant(date, endMinute!);
}
export function durationLabel(
  alarm: Pick<NotdienstAlarm, "wholeDay" | "startMinute" | "endMinute">,
) {
  return alarm.wholeDay
    ? "Ganzer Kita-Tag"
    : `${minuteClock(alarm.startMinute!)}–${minuteClock(alarm.endMinute!)} Uhr`;
}
export function instantLabel(value: Date | string) {
  return new Intl.DateTimeFormat("de-DE", {
    timeZone: "Europe/Berlin",
    day: "2-digit",
    month: "2-digit",
    hour: "2-digit",
    minute: "2-digit",
  }).format(new Date(value));
}
export function alarmLabel(
  alarm: Pick<NotdienstAlarm, "status" | "deadline" | "expiresAt">,
  now = new Date(),
) {
  if (alarm.status === "CANCELLED") return "Storniert";
  if (alarm.status === "CONFIRMED") return "Übernahme bestätigt";
  if (alarm.status === "DECLINED") return "Klärung erforderlich – Absage";
  if (alarm.status === "LATE_CONFIRMATION")
    return "Verspätete Zusage – Freigabe erforderlich";
  if (alarm.status === "REVIEW_REQUIRED")
    return "Klärung erforderlich – bisherige Rückmeldungen prüfen";
  if (alarm.deadline <= now || alarm.expiresAt <= now)
    return "Klärung erforderlich – Frist abgelaufen";
  return "Antwort ausstehend";
}
export function needsClarification(
  alarm: Pick<NotdienstAlarm, "status" | "deadline" | "expiresAt">,
  now = new Date(),
) {
  return (
    !["CONFIRMED", "CANCELLED"].includes(alarm.status) &&
    (alarm.status !== "PENDING" ||
      alarm.deadline <= now ||
      alarm.expiresAt <= now)
  );
}