<?php

namespace Modules\Core\Catalog\Services;

use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\Model;
use Lunar\Models\Collection;
use Lunar\Models\Product;
use Lunar\Search\CollectionIndexer as BaseCollectionIndexer;

/**
 * Extends Lunar's own indexer so Modules\Core\Catalog\Services\CollectionService can
 * serve category browsing/nav AND single-collection lookups from Meilisearch alone,
 * the same reasoning as Modules\Core\Catalog\Services\ProductIndexer. Lunar's base
 * indexer only carries `id`/`name`/`created_at` — nowhere near enough for a storefront
 * category page or a nav tree. Adds:
 *   - parent_id, _lft, _rgt (filterable/sortable) — the nested-set tree position, so
 *     CollectionService can resolve "children of X" or build a full tree without a
 *     database read
 *   - collection_group_id (filterable) — mirrors Collection::scopeInGroup()
 *   - slugs (filterable) — every locale's Url::slug, so getBySlug() resolves from the
 *     index directly, no database read
 *   - thumbnail (display) — the collection's thumbnail image URL
 *   - ancestors (display) — [{id, name}, ...] ordered root-first, so a breadcrumb can
 *     render directly from a single indexed document with zero extra queries
 *   - product_count (display) — how many products are in this collection or any of
 *     its descendants, read from the *product* Meilisearch index at collection-index
 *     time (via `collection_ids`, see Modules\Core\Catalog\Services\ProductIndexer) —
 *     matches what ProductService::list(ProductFilters(collectionId: ...)) would
 *     return, not just direct assignment. Reflects the product index's state as of
 *     the last collection reindex, so re-run `lunar:search:index --refresh` after a
 *     product reindex if this needs to be current.
 *
 * New fields aren't filterable/sortable in Meilisearch until `php artisan
 * lunar:meilisearch:setup` re-syncs index settings, and existing documents need
 * `lunar:search:index --refresh` to pick up the new shape.
 */
class CollectionIndexer extends BaseCollectionIndexer
{
    public function getFilterableFields(): array
    {
        return [
            ...parent::getFilterableFields(),
            'id',
            'parent_id',
            '_lft',
            'collection_group_id',
            'slugs',
        ];
    }

    public function getSortableFields(): array
    {
        return [
            ...parent::getSortableFields(),
            '_lft',
        ];
    }

    public function makeAllSearchableUsing(Builder $query): Builder
    {
        return parent::makeAllSearchableUsing($query)->with(['urls', 'media', 'ancestors']);
    }

    public function toSearchableArray(Model $model): array
    {
        /** @var Collection $model */
        $data = parent::toSearchableArray($model);

        $data['parent_id'] = $model->parent_id;
        $data['_lft'] = $model->_lft;
        $data['_rgt'] = $model->_rgt;
        $data['collection_group_id'] = $model->collection_group_id;
        $data['slugs'] = $model->urls->pluck('slug')->unique()->values()->all();
        $data['thumbnail'] = $model->getThumbnailImage() ?: null;
        $data['ancestors'] = $model->ancestors
            ->sortBy('_lft')
            ->map(fn ($ancestor) => [
                'id' => $ancestor->id,
                'name' => $ancestor->translateAttribute('name'),
            ])
            ->values()
            ->all();
        $data['product_count'] = Product::search('')
            ->options(['filter' => "collection_ids = \"{$model->id}\""])
            ->paginateRaw(perPage: 1, page: 1)
            ->total();

        return $data;
    }
}