"use client";

import { useState, useEffect } from "react";
import { createPortal } from "react-dom";
import { X } from "lucide-react";
import { adminFetch } from "@/lib/csrf";

type Tab = "classes" | "events";
type EventType = "master-class" | "open-day";

interface McOption { title: string; date: string }
interface OdClass { id: number; style: string; time: string; hall: string }
interface OdEvent { id: number; date: string; title?: string }

export function AddBookingModal({
  open,
  onClose,
  onAdded,
}: {
  open: boolean;
  onClose: () => void;
  onAdded: () => void;
}) {
  const [tab, setTab] = useState<Tab>("classes");
  const [eventType, setEventType] = useState<EventType>("master-class");
  const [name, setName] = useState("");
  const [phone, setPhone] = useState("");
  const [instagram, setInstagram] = useState("");
  const [telegram, setTelegram] = useState("");
  const [mcTitle, setMcTitle] = useState("");
  const [mcOptions, setMcOptions] = useState<McOption[]>([]);
  const [odClasses, setOdClasses] = useState<OdClass[]>([]);
  const [odEventId, setOdEventId] = useState<number | null>(null);
  const [odClassId, setOdClassId] = useState("");
  const [saving, setSaving] = useState(false);

  useEffect(() => {
    if (!open) return;
    setName(""); setPhone(""); setInstagram(""); setTelegram(""); setMcTitle(""); setOdClassId("");

    // Fetch upcoming MCs (filter out expired)
    adminFetch("/api/admin/sections/masterClasses").then((r) => r.json()).then((data: { items?: { title: string; slots: { date: string }[] }[] }) => {
      const today = new Date().toISOString().split("T")[0];
      const upcoming = (data.items || [])
        .filter((mc) => {
          const earliest = mc.slots?.reduce((min, s) => s.date < min ? s.date : min, mc.slots[0]?.date ?? "");
          return earliest && earliest >= today;
        })
        .map((mc) => ({
          title: mc.title,
          date: mc.slots.reduce((min, s) => s.date < min ? s.date : min, mc.slots[0]?.date ?? ""),
        }));
      setMcOptions(upcoming);
      if (upcoming.length === 0 && tab === "events") setEventType("open-day");
    }).catch(() => {});

    // Fetch active Open Day event + classes
    adminFetch("/api/admin/open-day").then((r) => r.json()).then(async (events: OdEvent[]) => {
      const today = new Date().toISOString().split("T")[0];
      const active = events.find((e) => e.date >= today);
      if (!active) { setOdEventId(null); setOdClasses([]); return; }
      setOdEventId(active.id);
      const classes = await adminFetch(`/api/admin/open-day/classes?eventId=${active.id}`).then((r) => r.json());
      setOdClasses(classes);
    }).catch(() => {});
  // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [open]);

  useEffect(() => {
    if (!open) return;
    function onKey(e: KeyboardEvent) { if (e.key === "Escape") onClose(); }
    document.addEventListener("keydown", onKey);
    return () => document.removeEventListener("keydown", onKey);
  }, [open, onClose]);

  const hasUpcomingMc = mcOptions.length > 0;
  const hasOpenDay = odEventId !== null && odClasses.length > 0;
  const hasEvents = hasUpcomingMc || hasOpenDay;

  async function handleSubmit() {
    if (!name.trim() || !phone.trim()) return;
    setSaving(true);
    try {
      if (tab === "classes") {
        await adminFetch("/api/admin/group-bookings", {
          method: "POST",
          headers: { "Content-Type": "application/json" },
          body: JSON.stringify({
            name: name.trim(),
            phone: phone.trim(),
            ...(instagram.trim() && { instagram: instagram.trim() }),
            ...(telegram.trim() && { telegram: telegram.trim() }),
          }),
        });
      } else if (eventType === "master-class") {
        const title = mcTitle || mcOptions[0]?.title || "Мастер-класс";
        await adminFetch("/api/admin/mc-registrations", {
          method: "POST",
          headers: { "Content-Type": "application/json" },
          body: JSON.stringify({ masterClassTitle: title, name: name.trim(), instagram: "-", phone: phone.trim() }),
        });
      } else if (eventType === "open-day" && odClassId && odEventId) {
        await adminFetch("/api/open-day-register", {
          method: "POST",
          headers: { "Content-Type": "application/json" },
          body: JSON.stringify({ classId: Number(odClassId), eventId: odEventId, name: name.trim(), phone: phone.trim() }),
        });
      }
      onAdded();
      onClose();
    } finally {
      setSaving(false);
    }
  }

  if (!open) return null;

  const inputClass = "w-full rounded-lg border border-white/[0.08] bg-white/[0.04] px-3 py-2 text-sm text-white outline-none focus:border-gold/40 placeholder-neutral-500";
  const tabBtn = (key: Tab, label: string, disabled?: boolean) => (
    <button
      key={key}
      onClick={() => !disabled && setTab(key)}
      disabled={disabled}
      className={`flex-1 rounded-lg py-2 text-xs font-medium transition-all ${
        tab === key ? "bg-gold/20 text-gold border border-gold/40" : "bg-neutral-800 text-neutral-400 border border-white/10 hover:text-white disabled:opacity-30 disabled:cursor-not-allowed"
      }`}
    >
      {label}
    </button>
  );

  const canSubmit = name.trim() && phone.trim() && !saving
    && (tab === "classes" || (tab === "events" && eventType === "master-class" && hasUpcomingMc)
    || (tab === "events" && eventType === "open-day" && odClassId));

  return createPortal(
    <div className="fixed inset-0 z-50 flex items-center justify-center p-4" onClick={onClose}>
      <div className="absolute inset-0 bg-black/70 backdrop-blur-sm" />
      <div className="relative w-full max-w-sm rounded-2xl border border-white/[0.08] bg-[#0a0a0a] p-6 shadow-2xl" onClick={(e) => e.stopPropagation()}>
        <button onClick={onClose} className="absolute right-3 top-3 flex h-7 w-7 items-center justify-center rounded-full text-neutral-500 hover:bg-white/[0.06] hover:text-white">
          <X size={16} />
        </button>

        <h3 className="text-base font-bold text-white">Добавить запись</h3>
        <p className="mt-1 text-xs text-neutral-400">Ручная запись (Instagram, звонок, лично)</p>

        <div className="mt-4 space-y-3">
          {/* Tab: Classes vs Events */}
          <div className="flex gap-2">
            {tabBtn("classes", "Занятие")}
            {tabBtn("events", "Мероприятие", !hasEvents)}
          </div>

          {/* Events sub-selector */}
          {tab === "events" && (
            <div className="flex gap-2">
              {hasUpcomingMc && (
                <button
                  onClick={() => setEventType("master-class")}
                  className={`flex-1 rounded-lg py-1.5 text-[11px] font-medium transition-all ${
                    eventType === "master-class" ? "bg-purple-500/15 text-purple-400 border border-purple-500/30" : "bg-neutral-800/50 text-neutral-500 border border-white/5 hover:text-neutral-300"
                  }`}
                >
                  Мастер-класс
                </button>
              )}
              {hasOpenDay && (
                <button
                  onClick={() => setEventType("open-day")}
                  className={`flex-1 rounded-lg py-1.5 text-[11px] font-medium transition-all ${
                    eventType === "open-day" ? "bg-blue-500/15 text-blue-400 border border-blue-500/30" : "bg-neutral-800/50 text-neutral-500 border border-white/5 hover:text-neutral-300"
                  }`}
                >
                  Open Day
                </button>
              )}
            </div>
          )}

          {/* MC selector */}
          {tab === "events" && eventType === "master-class" && mcOptions.length > 0 && (
            <select value={mcTitle} onChange={(e) => setMcTitle(e.target.value)} className={inputClass + " [color-scheme:dark]"}>
              <option value="" className="bg-neutral-900">Выберите мастер-класс</option>
              {mcOptions.map((mc) => (
                <option key={mc.title} value={mc.title} className="bg-neutral-900">
                  {mc.title}
                </option>
              ))}
            </select>
          )}

          {/* Open Day class selector */}
          {tab === "events" && eventType === "open-day" && odClasses.length > 0 && (
            <select value={odClassId} onChange={(e) => setOdClassId(e.target.value)} className={inputClass + " [color-scheme:dark]"}>
              <option value="" className="bg-neutral-900">Выберите занятие</option>
              {odClasses.map((c) => (
                <option key={c.id} value={c.id} className="bg-neutral-900">
                  {c.time} · {c.style} · {c.hall}
                </option>
              ))}
            </select>
          )}

          <input type="text" value={name} onChange={(e) => setName(e.target.value)} placeholder="Имя" className={inputClass} />
          <input type="tel" value={phone} onChange={(e) => setPhone(e.target.value)} placeholder="Телефон" className={inputClass} />
          <div className="flex gap-2">
            <input type="text" value={instagram} onChange={(e) => setInstagram(e.target.value)} placeholder="Instagram" className={inputClass} />
            <input type="text" value={telegram} onChange={(e) => setTelegram(e.target.value)} placeholder="Telegram" className={inputClass} />
          </div>
        </div>

        <button
          onClick={handleSubmit}
          disabled={!canSubmit}
          className="mt-5 w-full rounded-lg bg-gold py-2.5 text-sm font-semibold text-black transition-all hover:bg-gold-light disabled:opacity-30 disabled:cursor-not-allowed"
        >
          {saving ? "Сохраняю..." : "Добавить"}
        </button>
      </div>
    </div>,
    document.body
  );
}