"use client";

import { useState, useTransition } from "react";
import { useRouter } from "next/navigation";
import { Pencil, Undo2 } from "lucide-react";
import { AbsenceReason } from "@prisma/client";
import { toast } from "sonner";
import { deleteAbsence, updateAbsence } from "@/actions/absences";
import { absenceDate, canEditOwnAbsence } from "@/lib/absence-policy";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { Textarea } from "@/components/ui/textarea";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";

export type ManagedAbsence = {
  id: string;
  childName: string;
  startDate: string;
  endDate: string;
  reason: AbsenceReason;
  note: string | null;
  updatedAt: string;
};

export function AbsenceManagementActions({
  absence,
  today,
  team = false,
  onChanged,
}: {
  absence: ManagedAbsence;
  today: string;
  team?: boolean;
  onChanged?: () => void;
}) {
  const [mode, setMode] = useState<"edit" | "withdraw" | null>(null);
  const [pending, startTransition] = useTransition();
  const [error, setError] = useState<string | null>(null);
  const [startDate, setStartDate] = useState(absence.startDate);
  const [endDate, setEndDate] = useState(absence.endDate);
  const router = useRouter();
  if (!team && !canEditOwnAbsence(absence.startDate, today))
    return (
      <p className="mt-2 text-xs text-[var(--ink-muted)]">
        Bereits begonnene Meldung: Änderungen über die Kita.
      </p>
    );
  const tomorrow = new Date(absenceDate(today).getTime() + 86_400_000)
    .toISOString()
    .slice(0, 10);
  function open(next: "edit" | "withdraw") {
    setStartDate(absence.startDate);
    setEndDate(absence.endDate);
    setError(null);
    setMode(next);
  }
  function submit(data?: FormData) {
    startTransition(async () => {
      try {
        const identity = { id: absence.id, updatedAt: absence.updatedAt };
        const result =
          mode === "withdraw"
            ? await deleteAbsence(identity)
            : await updateAbsence({
                ...identity,
                startDate,
                endDate,
                reason: String(data?.get("reason") ?? ""),
                note: String(data?.get("note") ?? ""),
              });
        if (result.error) {
          setError(result.error);
          return;
        }
        toast.success(
          mode === "withdraw"
            ? "Abwesenheitsmeldung zurückgenommen."
            : "Abwesenheitsmeldung aktualisiert.",
        );
        setMode(null);
        onChanged?.();
      } catch {
        setError(
          "Die Meldung konnte nicht gespeichert werden. Bitte erneut versuchen.",
        );
      }
    });
  }
  return (
    <div className="mt-2 flex flex-wrap gap-2">
      <Button
        type="button"
        variant="outline"
        size="sm"
        onClick={() => open("edit")}
        aria-label={`Abwesenheit bearbeiten: ${absence.childName}`}
      >
        <Pencil className="h-3.5 w-3.5" /> Bearbeiten
      </Button>
      <Button
        type="button"
        variant="ghost"
        size="sm"
        onClick={() => open("withdraw")}
        aria-label={`Abwesenheit zurücknehmen: ${absence.childName}`}
      >
        <Undo2 className="h-3.5 w-3.5" /> Zurücknehmen
      </Button>
      <Dialog
        open={mode !== null}
        onOpenChange={(isOpen) => {
          if (!isOpen && !pending) setMode(null);
        }}
      >
        <DialogContent>
          <DialogHeader>
            <DialogTitle>
              {mode === "withdraw"
                ? "Abwesenheit zurücknehmen"
                : "Abwesenheit bearbeiten"}
            </DialogTitle>
            <DialogDescription>
              {absence.childName}
              {mode === "withdraw"
                ? ": Diese Meldung wird aus der Abwesenheitsübersicht entfernt."
                : ": Passe den Zeitraum, den Grund oder die Bemerkung an."}
              {!team && mode === "edit"
                ? " Änderungen sind nur für zukünftige Tage möglich."
                : ""}
            </DialogDescription>
          </DialogHeader>
          <form
            onSubmit={(event) => {
              event.preventDefault();
              submit(new FormData(event.currentTarget));
            }}
          >
            {mode === "edit" && (
              <fieldset disabled={pending} className="grid gap-4 py-4">
                <div className="grid grid-cols-2 gap-4">
                  <div className="grid gap-2">
                    <Label htmlFor={`absence-start-${absence.id}`}>Von</Label>
                    <Input
                      id={`absence-start-${absence.id}`}
                      type="date"
                      required
                      min={team ? undefined : tomorrow}
                      value={startDate}
                      onChange={(event) => {
                        const value = event.target.value;
                        setStartDate(value);
                        if (value > endDate) setEndDate(value);
                      }}
                    />
                  </div>
                  <div className="grid gap-2">
                    <Label htmlFor={`absence-end-${absence.id}`}>Bis</Label>
                    <Input
                      id={`absence-end-${absence.id}`}
                      type="date"
                      required
                      min={startDate}
                      value={endDate}
                      onChange={(event) => setEndDate(event.target.value)}
                    />
                  </div>
                </div>
                <div className="grid gap-2">
                  <Label htmlFor={`absence-reason-${absence.id}`}>Grund</Label>
                  <select
                    id={`absence-reason-${absence.id}`}
                    name="reason"
                    defaultValue={absence.reason}
                    className="h-10 rounded-lg border border-[var(--hairline)] bg-[var(--surface)] px-3 text-sm"
                    required
                  >
                    <option value={AbsenceReason.ILLNESS}>Krank</option>
                    <option value={AbsenceReason.VACATION}>Urlaub</option>
                    <option value={AbsenceReason.OTHER}>Sonstiges</option>
                  </select>
                </div>
                <div className="grid gap-2">
                  <Label htmlFor={`absence-note-${absence.id}`}>
                    Bemerkung (optional)
                  </Label>
                  <Textarea
                    id={`absence-note-${absence.id}`}
                    name="note"
                    maxLength={500}
                    defaultValue={absence.note ?? ""}
                    rows={3}
                  />
                </div>
              </fieldset>
            )}
            {error && (
              <div
                role="alert"
                className="my-4 rounded-lg bg-[var(--danger-soft)] p-3 text-sm text-[var(--danger)]"
              >
                {error}
                {error.includes("aktualisieren") && (
                  <Button
                    type="button"
                    variant="ghost"
                    size="sm"
                    onClick={() => {
                      setMode(null);
                      onChanged?.();
                      router.refresh();
                    }}
                  >
                    Ansicht aktualisieren
                  </Button>
                )}
              </div>
            )}
            <DialogFooter className="mt-4">
              <Button
                type="button"
                variant="ghost"
                disabled={pending}
                onClick={() => setMode(null)}
              >
                Abbrechen
              </Button>
              <Button
                type="submit"
                disabled={pending}
                variant={mode === "withdraw" ? "destructive" : "default"}
              >
                {pending
                  ? "Wird gespeichert…"
                  : mode === "withdraw"
                    ? "Meldung zurücknehmen"
                    : "Änderungen speichern"}
              </Button>
            </DialogFooter>
          </form>
        </DialogContent>
      </Dialog>
    </div>
  );
}