<?php
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

/**
 * Public live search for gallery titles.
 */
final class SG7G_Search {
    private const REST_NAMESPACE = '7sgaleri/v1';
    private const REST_ROUTE     = '/search';

    public static function init(): void {
        add_filter( 'query_vars', array( __CLASS__, 'query_vars' ) );
        add_filter( 'posts_clauses', array( __CLASS__, 'filter_posts_clauses' ), 10, 2 );
        add_action( 'rest_api_init', array( __CLASS__, 'register_rest_route' ) );
    }

    public static function query_vars( array $vars ): array {
        $vars[] = 'sg7q';
        $vars[] = 'sg7type';
        $vars[] = 'sg7cat';
        $vars[] = 'sg7year';
        $vars[] = 'sg7sort';
        return array_values( array_unique( $vars ) );
    }

    public static function request_term(): string {
        $term = get_query_var( 'sg7q', '' );
        if ( ! is_string( $term ) ) {
            return '';
        }

        return self::sanitize_term( $term );
    }

    public static function sanitize_term( string $term ): string {
        $term = sanitize_text_field( wp_unslash( $term ) );
        $term = preg_replace( '/\s+/u', ' ', trim( $term ) );

        return function_exists( 'mb_substr' )
            ? (string) mb_substr( $term, 0, 80 )
            : substr( $term, 0, 80 );
    }

    /**
     * Search only the post title.
     */
    public static function filter_posts_clauses( array $clauses, WP_Query $query ): array {
        $term = $query->get( 'sg7g_search_term' );
        $live_likes_sort = (bool) $query->get( 'sg7g_live_likes_sort' );
        if ( ( ! is_string( $term ) || '' === trim( $term ) ) && ! $live_likes_sort ) {
            return $clauses;
        }

        global $wpdb;

        if ( $live_likes_sort ) {
            $table = SG7G_Likes::table_name();
            if ( false === strpos( $clauses['join'], $table ) ) {
                $clauses['join'] .= " LEFT JOIN {$table} AS sg7g_live_likes ON sg7g_live_likes.post_id = {$wpdb->posts}.ID";
            }
            $clauses['groupby'] = $clauses['groupby']
                ? $clauses['groupby'] . ", {$wpdb->posts}.ID"
                : "{$wpdb->posts}.ID";
            $clauses['orderby'] = "COUNT(sg7g_live_likes.id) DESC, {$wpdb->posts}.post_date DESC";
        }

        if ( is_string( $term ) && '' !== trim( $term ) ) {
            $like = '%' . $wpdb->esc_like( self::sanitize_term( $term ) ) . '%';
            $clauses['where'] .= $wpdb->prepare( " AND {$wpdb->posts}.post_title LIKE %s", $like );
        }

        return $clauses;
    }

    public static function register_rest_route(): void {
        register_rest_route(
            self::REST_NAMESPACE,
            self::REST_ROUTE,
            array(
                'methods'             => WP_REST_Server::READABLE,
                'callback'            => array( __CLASS__, 'rest_search' ),
                'permission_callback' => '__return_true',
                'args'                => array(
                    'term' => array(
                        'default'           => '',
                        'sanitize_callback' => array( __CLASS__, 'sanitize_term' ),
                    ),
                    'page' => array(
                        'default'           => 1,
                        'sanitize_callback' => 'absint',
                        'validate_callback' => static function ( $value ): bool {
                            return absint( $value ) >= 1;
                        },
                    ),
                    'taxonomy' => array(
                        'default'           => '',
                        'sanitize_callback' => 'sanitize_key',
                        'validate_callback' => static function ( $value ): bool {
                            return in_array( (string) $value, array( '', 'sg7g_category', 'sg7g_tag' ), true );
                        },
                    ),
                    'term_id' => array(
                        'default'           => 0,
                        'sanitize_callback' => 'absint',
                    ),
                    'media_type' => array(
                        'default'           => '',
                        'sanitize_callback' => 'sanitize_key',
                        'validate_callback' => static function ( $value ): bool {
                            return in_array( (string) $value, array( '', 'video', 'audio' ), true );
                        },
                    ),
                    'category' => array(
                        'default'           => 0,
                        'sanitize_callback' => 'absint',
                    ),
                    'year' => array(
                        'default'           => 0,
                        'sanitize_callback' => 'absint',
                    ),
                    'sort' => array(
                        'default'           => 'newest',
                        'sanitize_callback' => 'sanitize_key',
                        'validate_callback' => static function ( $value ): bool {
                            return in_array( (string) $value, array( 'newest', 'oldest', 'views', 'likes' ), true );
                        },
                    ),
                ),
            )
        );
    }

    public static function rest_search( WP_REST_Request $request ): WP_REST_Response {
        $term     = self::sanitize_term( (string) $request->get_param( 'term' ) );
        $page     = min( 10000, max( 1, absint( $request->get_param( 'page' ) ) ) );
        $taxonomy = sanitize_key( (string) $request->get_param( 'taxonomy' ) );
        $term_id  = absint( $request->get_param( 'term_id' ) );
        $media_type = sanitize_key( (string) $request->get_param( 'media_type' ) );
        $category   = absint( $request->get_param( 'category' ) );
        $year       = absint( $request->get_param( 'year' ) );
        $sort       = sanitize_key( (string) $request->get_param( 'sort' ) );
        $sort       = in_array( $sort, array( 'newest', 'oldest', 'views', 'likes' ), true ) ? $sort : 'newest';

        $query_args = array(
            'post_type'           => 'sg7g_media',
            'post_status'         => 'publish',
            'has_password'        => false,
            'posts_per_page'      => max( 1, (int) SG7G_Settings::get( 'posts_per_page', 12 ) ),
            'paged'               => $page,
            'ignore_sticky_posts' => true,
            'sg7g_search_term'     => $term,
            'no_found_rows'       => false,
        );

        if ( $taxonomy && $term_id && term_exists( $term_id, $taxonomy ) ) {
            // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_tax_query -- User-selected gallery category filter.
            $query_args['tax_query'] = array(
                array(
                    'taxonomy' => $taxonomy,
                    'field'    => 'term_id',
                    'terms'    => array( $term_id ),
                ),
            );
        }

        if ( in_array( $media_type, array( 'video', 'audio' ), true ) ) {
            $query_args['meta_query'] = array(
                array(
                    'key'   => '_sg7g_media_type',
                    'value' => $media_type,
                ),
            );
        }

        if ( $category > 0 && term_exists( $category, 'sg7g_category' ) ) {
            $query_args['tax_query'] = isset( $query_args['tax_query'] ) && is_array( $query_args['tax_query'] ) ? $query_args['tax_query'] : array();
            $query_args['tax_query'][] = array(
                'taxonomy' => 'sg7g_category',
                'field'    => 'term_id',
                'terms'    => array( $category ),
            );
        }

        if ( $year >= 1970 && $year <= 2100 ) {
            $query_args['date_query'] = array( array( 'year' => $year ) );
        }

        switch ( $sort ) {
            case 'oldest':
                $query_args['orderby'] = 'date';
                $query_args['order']   = 'ASC';
                break;
            case 'views':
                $query_args['meta_key'] = '_sg7g_views';
                $query_args['orderby']  = array( 'meta_value_num' => 'DESC', 'date' => 'DESC' );
                $query_args['order']    = 'DESC';
                break;
            case 'likes':
                // filter_posts_clauses performs a live COUNT(*); no
                // aggregate like-count meta is used for ordering.
                $query_args['sg7g_live_likes_sort'] = true;
                $query_args['orderby']              = 'date';
                $query_args['order']    = 'DESC';
                break;
            case 'newest':
            default:
                $query_args['orderby'] = 'date';
                $query_args['order']   = (string) SG7G_Settings::get( 'sort_order', 'DESC' );
                break;
        }

        $search_query = new WP_Query( $query_args );

        // A stale browser-history URL can point beyond the last available
        // results page after content is removed. Return the real last page
        // instead of a misleading empty result set.
        $max_pages = max( 0, (int) $search_query->max_num_pages );
        if ( $search_query->found_posts > 0 && $max_pages > 0 && $page > $max_pages ) {
            $page                = $max_pages;
            $query_args['paged'] = $page;
            $search_query        = new WP_Query( $query_args );
        }

        ob_start();
        while ( $search_query->have_posts() ) {
            $search_query->the_post();
            SG7G_Renderer::card();
        }
        $cards_html = (string) ob_get_clean();
        wp_reset_postdata();

        $total = (int) $search_query->found_posts;
        $pages = max( 0, (int) $search_query->max_num_pages );

        $status = '';
        if ( '' !== $term ) {
            $status = 0 === $total
                ? __( 'No content matched your search.', '7sgaleri' )
                : sprintf(
                    /* translators: %s is the number of search results. */
                    /* translators: %s: Number of search results. */ _n( '%s result found.', '%s results found.', $total, '7sgaleri' ),
                    number_format_i18n( $total )
                );
        }

        $response = new WP_REST_Response(
            array(
                'html'       => $cards_html,
                'total'      => $total,
                'page'       => $page,
                'pages'      => $pages,
                'status'     => $status,
                'emptyText'  => __( 'No content matched your search.', '7sgaleri' ),
            ),
            200
        );
        $response->header( 'Cache-Control', 'no-store, no-cache, must-revalidate, max-age=0' );
        $response->header( 'Pragma', 'no-cache' );
        $response->header( 'X-Robots-Tag', 'noindex, nofollow' );

        return $response;
    }
}