<?php

declare(strict_types=1);

namespace App\Services\Recommendations;

use App\Models\Artwork;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;

final class SimilarArtworksService
{
    /**
     * @return Collection<int, Artwork>
     */
    public function forArtwork(int $artworkId, int $limit = 12, ?string $algoVersion = null): Collection
    {
        $effectiveAlgo = $algoVersion ?: (string) config('recommendations.embedding.algo_version', 'clip-cosine-v1');

        $ids = DB::table('artwork_similarities')
            ->where('artwork_id', $artworkId)
            ->where('algo_version', $effectiveAlgo)
            ->orderBy('rank')
            ->limit(max(1, min($limit, 50)))
            ->pluck('similar_artwork_id')
            ->map(static fn ($id) => (int) $id)
            ->all();

        if ($ids === []) {
            return collect();
        }

        $artworks = Artwork::query()
            ->whereIn('id', $ids)
            ->public()
            ->published()
            ->get();

        $byId = $artworks->keyBy('id');

        return collect($ids)
            ->map(static fn (int $id) => $byId->get($id))
            ->filter();
    }
}