<?php

declare(strict_types=1);

namespace FacetCore\WordPress;

final class RestController
{
    public function register(): void
    {
        register_rest_route('facetcore/v1', '/search', [
            'methods' => 'POST',
            'callback' => [$this, 'search'],
            // Public product search: no authentication, but every input is typed and bounded.
            'permission_callback' => '__return_true',
            'args' => self::searchArgs(),
        ]);
    }

    /** Request limits for /facetcore/v1/search; violations are rejected by core with HTTP 400. */
    private static function searchArgs(): array
    {
        return apply_filters('facetcore_rest_search_args', [
            'query' => ['type' => 'string', 'maxLength' => 200],
            'page' => ['type' => 'integer', 'minimum' => 1, 'maximum' => 1000000],
            'per_page' => ['type' => 'integer', 'minimum' => 1, 'maximum' => 100],
            // Facet ID => value ID; Finder supports at most ten simultaneous facets.
            'filters' => ['type' => 'object', 'maxProperties' => 10, 'additionalProperties' => ['type' => 'integer', 'minimum' => 1]],
        ]);
    }

    public function search(\WP_REST_Request $request)
    {
        $filters = $request->get_param('filters');
        $filters = is_array($filters) ? $filters : [];
        $page = is_scalar($request->get_param('page')) ? max(1, min(1000000, (int) $request->get_param('page'))) : 1;
        $perPage = is_scalar($request->get_param('per_page')) ? (int) $request->get_param('per_page') : 20;
        $query = $request->get_param('query');
        if ($query !== null && !is_string($query)) { return new \WP_Error('facetcore_invalid_search', __('Enter a valid search phrase.', 'facetcore'), ['status' => 400]); }
        $query = mb_substr(sanitize_text_field($query ?? ''), 0, 200);

        global $wpdb;
        $previousErrors = $wpdb->suppress_errors(true);
        try {
            $repo = new Repository();
            foreach ([$repo->facetTable(), $repo->valueTable(), $repo->productValueTable()] as $table) {
                if ($wpdb->get_var($wpdb->prepare('SHOW TABLES LIKE %s', $wpdb->esc_like($table))) !== $table) { throw new \RuntimeException('Index unavailable.'); }
            }
            $config = TableConfiguration::effective(array_diff_key(TableConfiguration::defaults(), array_flip(TableConfiguration::extensionKeys())));
            $resolved = null;
            $rawId = $request->get_param('table_id');
            if ($rawId !== null) {
                if (!is_scalar($rawId) || !preg_match('/^[1-9][0-9]*$/D', (string) $rawId)) { return new \WP_Error('facetcore_invalid_table', __('Finder unavailable.', 'facetcore'), ['status' => 404]); }
                $config = TableConfiguration::get((int) $rawId);
                if (!$config) { return new \WP_Error('facetcore_invalid_table', __('Finder unavailable.', 'facetcore'), ['status' => 404]); }
                $resolved = TableConfiguration::resolve($config);
                $perPage = $config['per_page'];
            }
            if ($resolved && !$config['enable_search']) { $query = ''; }
            $filters = apply_filters('facetcore_request_filters', $filters, $request, $resolved, $repo);
            $result = (new Finder(null, null, null, $resolved['facets'] ?? null, $resolved ? TableConfiguration::categoryScope($config) : null, $query))->search($filters, $page, $perPage);
            $result['query'] = $query;
            $result['settings'] = array_intersect_key($config, array_flip(['show_counts', 'enable_search', 'views', 'default_view', 'allow_switch', 'grid_sku']));
            if ($resolved !== null) {
                $result['columns'] = $resolved['columns'];
                $result['settings'] = array_intersect_key($config, array_flip(['show_counts', 'enable_search', 'views', 'default_view', 'allow_switch', 'grid_sku']));
                $result['grid_attributes'] = $resolved['grid_attributes'];
                if (!$resolved['settings']['hide_impossible']) {
                    $allValues = (new Repository())->valuesForFacets(array_column($result['facets'], 'facet_id'));
                    foreach ($result['facets'] as &$facet) {
                        $present = array_column($facet['values'], 'id');
                        foreach ($allValues[$facet['facet_id']] ?? [] as $value) {
                            if (!in_array((int) $value['id'], $present, true)) { $facet['values'][] = ['id' => (int) $value['id'], 'label' => $value['label'], 'products' => 0]; }
                        }
                    }
                    unset($facet);
                }
            }
            $result = apply_filters('facetcore_search_result', $result, $resolved);
            $result['products'] = $this->products($result['ids'], $result['facets'], array_merge($resolved['columns'] ?? [], $resolved['grid_attributes'] ?? []));
            unset($result['ids']);
            return rest_ensure_response($result);
        } catch (\Throwable $e) {
            return new \WP_Error('facetcore_search_failed', __('Unable to load products.', 'facetcore'), ['status' => 500]);
        } finally { $wpdb->suppress_errors($previousErrors); }
    }

    private function products(array $ids, array $facets, array $columns = []): array
    {
        $products = [];
        // Prime native caches once for the bounded result page, before Woo product hydration.
        if ($ids) { _prime_post_caches($ids, true, true); }
        $facetIds = array_map(static function (array $facet): int {
            return (int) $facet['facet_id'];
        }, $facets);
        $parameters = (new Repository())->labelsForProducts($ids, $facetIds);
        $attributeRows = apply_filters('facetcore_product_attributes', [], $ids, $columns);
        foreach ($ids as $id) {
            $product = wc_get_product($id);
            if (!$product || !$product->is_visible()) {
                continue;
            }
            $attributes = [];
            foreach ($columns as $column) {
                if (isset($column['taxonomy'])) {
                    $attributes[$column['key']] = $attributeRows[$id][$column['key']] ?? [];
                }
            }
            $products[] = [
                'attributes' => $attributes,
                'id' => $product->get_id(),
                'name' => $product->get_name(),
                'sku' => $product->get_sku(),
                // The client inserts WooCommerce price markup as HTML, including filtered prices.
                'price_html' => wp_kses_post($product->get_price_html()),
                'stock_status' => $product->get_stock_status(),
                // JSON consumers escape attributes; reject unsafe URL protocols here as well.
                'permalink' => esc_url_raw($product->get_permalink()),
                'image' => esc_url_raw(wp_get_attachment_image_url($product->get_image_id(), 'woocommerce_thumbnail') ?: wc_placeholder_img_src('woocommerce_thumbnail')),
                'add_to_cart_url' => esc_url_raw($product->is_type('simple') && $product->is_purchasable() && $product->is_in_stock() ? add_query_arg('add-to-cart', $product->get_id(), $product->get_permalink()) : $product->get_permalink()),
                // WooCommerce supplies (and translates) the label where its own text matches: simple purchasable in-stock
                // products and purchasable variable products ("Select options"). Other cases keep FacetCore's labels.
                'add_to_cart_text' => $product->is_type('variable') ? ($product->is_purchasable() ? $product->add_to_cart_text() : __('Select options', 'facetcore')) : ($product->is_type('simple') && $product->is_purchasable() && $product->is_in_stock() ? $product->add_to_cart_text() : __('View product', 'facetcore')),
                'parameters' => $parameters[$product->get_id()] ?? [],
            ];
        }
        return $products;
    }
}