import { useEffect, useMemo, useState } from 'react';
import { Link, useSearchParams } from 'react-router';
import { Search, Sparkles } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { useClient } from 'hooks/useClient';
import { AssetViewer } from './AssetViewer';
import { PhotoGrid } from './PhotoGrid';
import { SelectionBar } from './SelectionBar';
import { ALBUM_PARAM, QUERY_PARAM, photosSectionPath, thumbUrl, toGridAsset } from './shared';
import { useSearch } from './usePhotosData';
import { useSelection } from './useSelection';

// Search. The query lives in `?q=`, so a search is a link — the same reason the lightbox lives in `?asset=`.
//
// Smart search is Immich's CLIP model ("red bicycle", "birthday cake") and is the default because it is the
// thing Immich has that a file browser does not. The toggle falls back to filename/metadata matching.

export const SearchSection = () => {
  const { token } = useClient();
  const [params, setParams] = useSearchParams();
  const submitted = params.get(QUERY_PARAM) ?? '';

  const [draft, setDraft] = useState(submitted);
  const [smart, setSmart] = useState(true);

  // The box follows the URL, so a link into /photos/search?q=… arrives with its own query already typed.
  useEffect(() => setDraft(submitted), [submitted]);

  const { data, isFetching } = useSearch({ query: submitted, smart, enabled: submitted.length > 0 });

  const assets = useMemo(() => (data?.assets.items ?? []).map(toGridAsset), [data]);
  const selection = useSelection(assets.map((asset) => asset.id));

  const submit = (ev: React.FormEvent) => {
    ev.preventDefault();
    setParams((current) => {
      const next = new URLSearchParams(current);
      if (draft.trim()) next.set(QUERY_PARAM, draft.trim());
      else next.delete(QUERY_PARAM);
      return next;
    });
  };

  return (
    <div className="flex h-full flex-col">
      {selection.isSelecting ? (
        <SelectionBar selection={selection} />
      ) : (
        <header className="flex items-center gap-2 border-b px-3 py-2">
          <form onSubmit={submit} className="flex flex-1 items-center gap-2">
            <Search className="h-4 w-4 shrink-0 text-muted-foreground" />
            <Input
              value={draft}
              onChange={(ev) => setDraft(ev.target.value)}
              placeholder={smart ? 'Describe a photo — "sunset over water"' : 'Filename or path'}
              className="h-8"
            />
            <Button type="submit" size="sm" variant="secondary">
              Search
            </Button>
          </form>
          <Button
            variant={smart ? 'default' : 'ghost'}
            size="sm"
            title="Smart search uses Immich's CLIP model instead of matching filenames"
            onClick={() => setSmart((value) => !value)}
          >
            <Sparkles className="mr-1.5 h-4 w-4" />
            Smart
          </Button>
        </header>
      )}

      <div className="min-h-0 flex-1 overflow-y-auto p-2">
        {!submitted && <p className="p-2 text-sm text-muted-foreground">Search your library.</p>}
        {submitted && isFetching && <p className="p-2 text-sm text-muted-foreground">Searching…</p>}

        {data && data.albums.items.length > 0 && (
          <section className="mb-4">
            <h2 className="mb-2 px-1 text-xs font-medium uppercase tracking-wide text-muted-foreground">Albums</h2>
            <div className="flex flex-wrap gap-3">
              {data.albums.items.map((album) => (
                <Link key={album.id} to={`${photosSectionPath('albums')}?${ALBUM_PARAM}=${album.id}`} className="w-32">
                  <div className="aspect-square overflow-hidden rounded-lg bg-white/5">
                    {album.albumThumbnailAssetId && (
                      <img
                        src={thumbUrl(album.albumThumbnailAssetId, token)}
                        alt=""
                        className="h-full w-full object-cover"
                      />
                    )}
                  </div>
                  <p className="mt-1 truncate text-xs">{album.albumName}</p>
                </Link>
              ))}
            </div>
          </section>
        )}

        {submitted && !isFetching && (
          <PhotoGrid
            assets={assets}
            token={token}
            selection={selection}
            empty={<p className="p-2 text-sm text-muted-foreground">No matches.</p>}
          />
        )}
      </div>

      <AssetViewer ids={assets.map((asset) => asset.id)} token={token} />
    </div>
  );
};