import { useEffect, useMemo, useState } from 'react';

import {
  featuredGifs,
  getRecentGifs,
  type GifResult,
  rememberRecentGif,
  searchGifs,
} from '../lib/tenor';
import { SpinnerIcon, XIcon } from './icons';

interface Props {
  open: boolean;
  onClose: () => void;
  onPick: (gif: GifResult) => void;
}

type Tab = 'trending' | 'search' | 'recent';

export function GifPicker({ open, onClose, onPick }: Props) {
  const [tab, setTab] = useState<Tab>('trending');
  const [query, setQuery] = useState('');
  const [results, setResults] = useState<GifResult[]>([]);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);

  const recent = useMemo(() => getRecentGifs(), [open]);

  useEffect(() => {
    if (!open) return;
    let cancelled = false;
    setLoading(true);
    setError(null);
    const run = async () => {
      try {
        const gifs = tab === 'search' && query.trim().length > 0
          ? await searchGifs(query)
          : tab === 'trending'
            ? await featuredGifs()
            : [];
        if (!cancelled) setResults(gifs);
      } catch (err) {
        if (!cancelled) setError(err instanceof Error ? err.message : 'GIFs gerade nicht verfügbar');
      } finally {
        if (!cancelled) setLoading(false);
      }
    };
    void run();
    return () => { cancelled = true; };
  }, [open, tab, query]);

  if (!open) return null;

  const visible = tab === 'recent' ? recent : results;

  return (
    <div className="absolute bottom-full left-0 z-30 mb-2 w-[440px] rounded-2xl border border-line bg-surface-2 shadow-xl">
      <header className="flex items-center justify-between border-b border-line px-3 py-2">
        <div className="flex items-center gap-1">
          {(['trending', 'search', 'recent'] as Tab[]).map((t) => (
            <button
              key={t}
              type="button"
              onClick={() => setTab(t)}
              className={
                'cursor-pointer rounded-md px-2 py-1 text-xs font-medium transition ' +
                (t === tab ? 'bg-accent/15 text-accent' : 'text-fg-muted hover:text-fg')
              }
            >
              {t === 'trending' ? 'Trending' : t === 'search' ? 'Suche' : 'Zuletzt'}
            </button>
          ))}
        </div>
        <button
          type="button"
          onClick={onClose}
          aria-label="Schließen"
          className="flex h-6 w-6 cursor-pointer items-center justify-center rounded-md text-fg-muted hover:bg-surface-3 hover:text-fg"
        >
          <XIcon className="h-3.5 w-3.5" />
        </button>
      </header>
      {tab === 'search' && (
        <div className="border-b border-line px-3 py-2">
          <input
            type="text"
            value={query}
            onChange={(e) => setQuery(e.target.value)}
            placeholder="GIFs suchen…"
            className="w-full rounded-md border border-line bg-surface-3 px-2 py-1.5 text-sm text-fg placeholder-fg-muted focus:border-accent focus:outline-none focus:ring-1 focus:ring-accent/40"
          />
        </div>
      )}
      <div className="grid max-h-[360px] grid-cols-3 gap-1.5 overflow-y-auto p-2">
        {loading && (
          <div className="col-span-3 flex justify-center py-6 text-fg-muted">
            <SpinnerIcon className="h-5 w-5" />
          </div>
        )}
        {error && (
          <p className="col-span-3 px-2 py-4 text-center text-xs text-rose-300">
            {error === 'giphy_api_key_missing'
              ? 'GIFs sind nicht konfiguriert (VITE_GIPHY_API_KEY fehlt).'
              : 'GIFs gerade nicht verfügbar.'}
          </p>
        )}
        {!loading && !error && visible.length === 0 && (
          <p className="col-span-3 px-2 py-6 text-center text-xs text-fg-muted">
            {tab === 'recent' ? 'Noch keine zuletzt verwendeten GIFs.' : 'Keine Treffer.'}
          </p>
        )}
        {!loading && !error && visible.map((g) => (
          <button
            key={g.id}
            type="button"
            onClick={() => { rememberRecentGif(g); onPick(g); onClose(); }}
            className="overflow-hidden rounded-md border border-line bg-surface-3 hover:border-accent/40"
            title={g.description}
          >
            <img src={g.previewUrl} alt={g.description || 'GIF'} className="h-24 w-full object-cover" loading="lazy" />
          </button>
        ))}
      </div>
    </div>
  );
}