import { useEffect, useRef, useState } from "react";
import Preloader from "./components/Preloader";
import AgeGate from "./components/AgeGate";
import Header from "./components/Header";
import Hero from "./components/Hero";
import AtmosphereCarousel from "./components/AtmosphereCarousel";
import MenuCarousel from "./components/MenuCarousel";
import VipCalculator from "./components/VipCalculator";
import Features from "./components/Features";
import Contacts from "./components/Contacts";
import Footer from "./components/Footer";
import FlavorsPage from "./pages/FlavorsPage";
import GamesPage from "./pages/GamesPage";
import MixesPage from "./pages/MixesPage";
import AiMixPage from "./pages/AiMixPage";
import BoardGamesPage from "./pages/BoardGamesPage";
import MenuPage from "./pages/MenuPage";
import TrackOrderPage from "./pages/TrackOrderPage";
import { useHashLocation } from "./hooks/useHashLocation";
import { isPrerender } from "./lib/prerender";

type CatalogPage = "flavors" | "games" | "mixes" | "ai-mix" | "board-games" | "menu" | "track" | null;

function getCatalogPage(hash: string): CatalogPage {
  if (hash === "#/flavors") return "flavors";
  if (hash === "#/games") return "games";
  if (hash === "#/mixes") return "mixes";
  if (hash === "#/ai-mix" || hash === "#/mix-builder") return "ai-mix";
  if (hash.startsWith("#mix=")) return "ai-mix"; // share-ссылка на генерацию
  if (hash === "#/board-games") return "board-games";
  if (hash === "#/menu" || hash === "#/tea") return "menu";
  if (hash.startsWith("#/track")) return "track"; // #/track и #/track?code=XXX
  return null;
}

export default function App() {
  const [loaded, setLoaded] = useState(false);
  const hash = useHashLocation();
  const catalogPage = getCatalogPage(hash);
  const isCatalog = catalogPage !== null;
  const wasCatalog = useRef(isCatalog);
  const homeTitle = useRef(document.title);
  // в пререндер-снапшоте рендерим финальное видимое состояние страницы
  const prerender = isPrerender();
  const started = loaded || prerender;

  useEffect(() => {
    const previousOverflow = document.body.style.overflow;
    document.body.style.overflow = "hidden";
    const t = setTimeout(() => {
      document.body.style.overflow = previousOverflow;
      setLoaded(true);
    }, 2450);
    return () => {
      clearTimeout(t);
      document.body.style.overflow = previousOverflow;
    };
  }, []);

  useEffect(() => {
    if (catalogPage === "flavors") {
      document.title = "Вкусы табака | НЕОН, Нягань";
    } else if (catalogPage === "games") {
      document.title = "Игры PS5 | НЕОН, Нягань";
    } else if (catalogPage === "mixes") {
      document.title = "Миксы кальянов | НЕОН, Нягань";
    } else if (catalogPage === "ai-mix") {
      document.title = "Автоподбор микса | НЕОН, Нягань";
    } else if (catalogPage === "board-games") {
      document.title = "Настольные игры | НЕОН, Нягань";
    } else if (catalogPage === "menu") {
      document.title = "Меню бара: Авторский чай и Пивная карта | НЕОН, Нягань";
    } else if (catalogPage === "track") {
      document.title = "Статус заказа | НЕОН, Нягань";
    } else {
      document.title = homeTitle.current;
    }
  }, [catalogPage]);

  useEffect(() => {
    if (!loaded) return;
    const returningToHome = wasCatalog.current && !isCatalog;
    wasCatalog.current = isCatalog;

    if (catalogPage === "flavors") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("flavors-title")?.focus({ preventScroll: true });
      return;
    }

    if (catalogPage === "games") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("games-title")?.focus({ preventScroll: true });
      return;
    }

    if (catalogPage === "mixes") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("mixes-title")?.focus({ preventScroll: true });
      return;
    }

    if (catalogPage === "ai-mix") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("ai-mix-title")?.focus({ preventScroll: true });
      return;
    }

    if (catalogPage === "board-games") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("board-games-title")?.focus({ preventScroll: true });
      return;
    }

    if (catalogPage === "menu") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("menu-page-title")?.focus({ preventScroll: true });
      return;
    }

    if (catalogPage === "track") {
      window.scrollTo({ top: 0, behavior: "instant" });
      document.getElementById("track-title")?.focus({ preventScroll: true });
      return;
    }

    // The landing section mounts after the hash changes when leaving the catalog.
    const section = document.getElementById(hash.slice(1) || "home");
    if (!section) return;
    const reducedMotion = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    section.scrollIntoView({
      block: "start",
      behavior: returningToHome || reducedMotion ? "instant" : "smooth",
    });
    if (returningToHome) {
      section.tabIndex = -1;
      section.focus({ preventScroll: true });
    }
  }, [hash, catalogPage, isCatalog, loaded]);

  return (
    <div className="relative min-h-screen w-full max-w-full overflow-x-hidden bg-void font-sans text-mist antialiased">
      <div className="noise" aria-hidden />
      {/* в пререндер-снапшоте прелоадер и age-gate не попадают в HTML:
          бот должен видеть финальную страницу, а не оверлеи */}
      {!prerender && <Preloader done={loaded} />}
      {!prerender && <AgeGate ready={loaded} />}
      <Header started={started} />
      <main className="w-full max-w-full overflow-x-hidden">
        {catalogPage === "flavors" ? (
          <FlavorsPage />
        ) : catalogPage === "games" ? (
          <GamesPage />
        ) : catalogPage === "mixes" ? (
          <MixesPage />
        ) : catalogPage === "ai-mix" ? (
          <AiMixPage />
        ) : catalogPage === "board-games" ? (
          <BoardGamesPage />
        ) : catalogPage === "menu" ? (
          <MenuPage />
        ) : catalogPage === "track" ? (
          <TrackOrderPage />
        ) : (
          <>
            <Hero started={started} />
            <AtmosphereCarousel />
            <MenuCarousel />
            <Features />
            <VipCalculator />
            <Contacts />
          </>
        )}
      </main>
      <Footer />
    </div>
  );
}