import { useEffect, useState } from "react";
import { BookOpen, LibraryBig, RotateCcw } from "lucide-react";
import type { BookDto, ProgressDto } from "@readabook/shared";
import { api, getApiFallback } from "../api/client";
import { EmptyState, ErrorRibbon, FormatPill, LoadingState, Meter, Panel } from "../components/ui";
import { navigate } from "../router";

export function BookPage({ bookId }: { bookId: number }) {
  const [book, setBook] = useState<BookDto | null>(null);
  const [progress, setProgress] = useState<ProgressDto | null>(null);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string>();

  async function loadBook() {
    setLoading(true);
    setError(undefined);
    try {
      const [nextBook, nextProgress] = await Promise.all([api.book(bookId), api.progress(bookId)]);
      setBook(nextBook);
      setProgress(nextProgress);
    } catch (loadError) {
      const fallback = getApiFallback<BookDto>(loadError);
      setBook(fallback ?? null);
      setProgress(null);
      setError(fallback ? "Fiche chargee en mode secours." : "Fiche livre indisponible.");
    } finally {
      setLoading(false);
    }
  }

  useEffect(() => {
    let alive = true;
    loadBook().finally(() => {
      if (!alive) return;
    });
    return () => {
      alive = false;
    };
  }, [bookId]);

  if (loading && !book) return <LoadingState />;
  if (!book) {
    return (
      <Panel>
        <EmptyState title="Fiche introuvable" detail={error ?? "Le catalogue n'a pas renvoye cet ouvrage."} />
        <button className="ghost-button" onClick={() => void loadBook()}>
          <RotateCcw size={17} />
          Reessayer
        </button>
      </Panel>
    );
  }

  return (
    <div className="book-detail">
      <section className="book-portrait">
        {book.coverPath ? <img src={api.bookCoverUrl(book.id)} alt="" /> : <BookOpen size={72} />}
      </section>
      <Panel className="book-facts">
        <ErrorRibbon message={error} />
        <div className="book-card-meta">
          <FormatPill format={book.format} />
          <span>{book.language ?? "langue inconnue"}</span>
        </div>
        <h1>{book.title}</h1>
        <p className="lead">{book.author ?? "Auteur inconnu"}</p>
        <p>{book.description ?? "Notice absente du catalogue."}</p>
        {progress && <Meter value={progress.percent} />}
        <div className="book-card-actions">
          <button className="primary-button" onClick={() => navigate(`/reader/${book.id}`)}>
            <BookOpen size={18} />
            Lire
          </button>
          <button className="ghost-button" onClick={() => navigate(`/library/${book.libraryId}`)}>
            <LibraryBig size={18} />
            Rayon
          </button>
          {error && (
            <button className="ghost-button" onClick={() => void loadBook()}>
              <RotateCcw size={18} />
              Reessayer
            </button>
          )}
        </div>
      </Panel>
    </div>
  );
}