"use client";

import { useEffect, useRef, useState } from "react";
import { useTranslations } from "next-intl";
import { AlertCircle, X } from "lucide-react";
import type { PlanningConflict } from "@/lib/planning/capacity";
import { formatMinutes } from "@/lib/planning/text";
import { wallTimeToUtc } from "@/lib/work-orders/time";
import { buttonCls } from "@/components/work-orders/button-cls";
import { Field, inputCls } from "@/components/work-orders/ui";
import type { BoardOrder } from "@/server/services/planning/data";

export type DialogState = { order: BoardOrder; teamId: string; day: string; time: string; duration: number };

export type ScheduleResponse = {
  id: string;
  number: string;
  version: number;
  status: string;
  teamId: string;
  plannedStart: string;
  plannedEnd: string | null;
  plannedDurationMinutes: number | null;
  conflicts: PlanningConflict[];
};

/**
 * Confirmation popover for drag & drop and the keyboard path ("Einplanen …"): team, date, start and
 * duration are prefilled; nothing is saved without "Speichern". Escape / backdrop / × close it and focus
 * returns to the element that opened it.
 */
export function ScheduleDialog({
  state,
  teams,
  timeZone,
  locale,
  onClose,
  onSaved,
  onConflict,
}: {
  state: DialogState;
  teams: { id: string; name: string }[];
  timeZone: string;
  locale: string;
  onClose: () => void;
  onSaved: (res: ScheduleResponse) => void;
  onConflict: (message: string) => void;
}) {
  const t = useTranslations("planning");
  const [teamId, setTeamId] = useState(state.teamId);
  const [day, setDay] = useState(state.day);
  const [time, setTime] = useState(state.time || "08:00");
  const [allDay, setAllDay] = useState(state.time === "");
  const [duration, setDuration] = useState(state.duration);
  const [pending, setPending] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const closeRef = useRef(onClose);

  useEffect(() => {
    closeRef.current = onClose;
  }, [onClose]);

  useEffect(() => {
    const opener = document.activeElement as HTMLElement | null;
    const onKey = (e: KeyboardEvent) => {
      if (e.key === "Escape") closeRef.current();
    };
    window.addEventListener("keydown", onKey);
    return () => {
      window.removeEventListener("keydown", onKey);
      opener?.focus?.();
    };
  }, []);

  const order = state.order;

  async function submit(e: React.FormEvent) {
    e.preventDefault();
    setError(null);
    const start = wallTimeToUtc(allDay ? day : `${day}T${time}`, timeZone);
    if (!start || !teamId || !Number.isFinite(duration) || duration < 15) {
      setError(t("errors.invalid"));
      return;
    }
    const body: Record<string, unknown> = { workOrderId: order.id, teamId, plannedStart: start.toISOString(), baseVersion: order.version };
    if (!order.multiDay) {
      body.plannedDurationMinutes = Math.round(duration);
      body.plannedEnd = allDay ? null : new Date(start.getTime() + Math.round(duration) * 60_000).toISOString();
    }
    setPending(true);
    try {
      const res = await fetch("/api/v1/planning/schedule", { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify(body) });
      const json = (await res.json().catch(() => null)) as (ScheduleResponse & { error?: { code?: string; message?: string } }) | null;
      if (res.ok && json) {
        onSaved(json);
        return;
      }
      if (res.status === 409) {
        onConflict(t("errors.conflict"));
        return;
      }
      const message = json?.error?.message ?? "";
      const code = json?.error?.code ?? "";
      setError(t.has(`errors.${message}`) ? t(`errors.${message}`) : t.has(`errors.${code}`) ? t(`errors.${code}`) : t("errors.generic"));
    } catch {
      setError(t("errors.network"));
    } finally {
      setPending(false);
    }
  }

  return (
    <div
      className="fixed inset-0 z-50 flex items-start justify-center overflow-y-auto bg-black/30 p-6 backdrop-blur-[2px]"
      onMouseDown={(e) => {
        if (e.target === e.currentTarget) onClose();
      }}
    >
      <div role="dialog" aria-modal="true" aria-labelledby="schedule-title" className="shadow-card my-auto w-full max-w-lg rounded-2xl border bg-card">
        <div className="flex items-start justify-between gap-3 border-b p-5">
          <div className="min-w-0">
            <h2 id="schedule-title" className="font-heading text-lg font-semibold">
              {t("dialog.title")}
            </h2>
            <p className="text-sm">
              <span className="font-mono">{order.number}</span> · {order.customerName}
            </p>
            {(order.siteAddress || order.siteName) && <p className="truncate text-xs text-muted-foreground">{order.siteAddress ?? order.siteName}</p>}
          </div>
          <button type="button" onClick={onClose} aria-label={t("dialog.close")} className="grid size-11 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-muted hover:text-foreground">
            <X className="size-4.5" aria-hidden />
          </button>
        </div>
        <form onSubmit={submit} className="grid gap-4 p-5 sm:grid-cols-2">
          <Field label={t("dialog.team")} htmlFor="sd-team" className="sm:col-span-2">
            <select id="sd-team" value={teamId} onChange={(e) => setTeamId(e.target.value)} required className={inputCls} autoFocus>
              {teams.map((tm) => (
                <option key={tm.id} value={tm.id}>
                  {tm.name}
                </option>
              ))}
            </select>
          </Field>
          <Field label={t("dialog.date")} htmlFor="sd-day">
            <input id="sd-day" type="date" value={day} onChange={(e) => setDay(e.target.value)} required className={inputCls} />
          </Field>
          <Field label={t("dialog.time")} htmlFor="sd-time">
            <input id="sd-time" type="time" step={900} value={time} onChange={(e) => setTime(e.target.value)} disabled={allDay} required={!allDay} className={inputCls} />
          </Field>
          <label className="flex min-h-11 items-center gap-2.5 text-sm sm:col-span-2">
            <input type="checkbox" checked={allDay} onChange={(e) => setAllDay(e.target.checked)} className="size-5 accent-[var(--ui-primary)]" />
            {t("dialog.noTime")}
          </label>
          {!order.multiDay && (
            <Field label={t("dialog.duration")} htmlFor="sd-duration" hint={t("dialog.durationHint", { duration: formatMinutes(order.durationMinutes, locale) })} className="sm:col-span-2">
              <input id="sd-duration" type="number" min={15} max={20160} step={15} value={duration} onChange={(e) => setDuration(Number(e.target.value))} required className={inputCls} />
            </Field>
          )}
          {error && (
            <p role="alert" className="flex items-center gap-2 rounded-lg border border-[var(--risk)] px-3 py-2 text-sm text-[var(--risk)] sm:col-span-2">
              <AlertCircle className="size-4 shrink-0" aria-hidden />
              {error}
            </p>
          )}
          <div className="flex flex-wrap gap-2 sm:col-span-2">
            <button type="submit" disabled={pending} className={buttonCls("primary")}>
              {pending ? t("dialog.saving") : t("dialog.save")}
            </button>
            <button type="button" onClick={onClose} className={buttonCls("ghost")}>
              {t("dialog.cancel")}
            </button>
          </div>
        </form>
      </div>
    </div>
  );
}