<?php

namespace StoreSuit;

defined( 'ABSPATH' ) || exit;
// phpcs:disable WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Messages are returned as JSON by Admin::ajax() and shown with textContent; HTML output escapes them where printed.
/** Capability-aware global search over existing records; it creates no second index. */
final class UniversalSearch {
    private static function result(
        string $type,
        int $id,
        string $title,
        string $detail,
        string $url
    ) : array {
        return array(
            'type'   => $type,
            'id'     => $id,
            'title'  => $title,
            'detail' => $detail,
            'url'    => admin_url( 'admin.php?page=' . $url ),
        );
    }

    /** Lower case without accents (â → a, ş → s, ı → i): how the database collation compares, for ranking only. */
    private static function plain( string $text ) : string {
        return remove_accents( mb_strtolower( str_replace( array('İ', 'ı'), array('i', 'i'), $text ) ) );
    }

    /**
     * How closely a record meets the search, for ordering a group (P1-27): the database also matches inside words and
     * ignores accents ("kâr" finds "Kara" and "Kartlık"), which stays useful for a partial SKU, so those come last instead
     * of being dropped. 0: a whole text or word is the search with its accents; 1: the same without accents; 2: a text or
     * word starts with it; 3: the same without accents; 4: it is inside a word. Every word of the search counts; the
     * weakest decides.
     */
    public static function rank( string $query, string ... $texts ) : int {
        // "İ" lowers to "i" (mb_strtolower would add a combining dot that splits the word).
        $lower = static fn( string $text ): string => mb_strtolower( str_replace( 'İ', 'i', trim( $text ) ) );
        $terms = ( preg_split(
            '/[^\\p{L}\\p{N}]+/u',
            $lower( $query ),
            -1,
            PREG_SPLIT_NO_EMPTY
        ) ?: array() );
        if ( !$terms ) {
            return 4;
        }
        $words = array();
        foreach ( $texts as $text ) {
            $text = $lower( $text );
            if ( $text === '' ) {
                continue;
            }
            $words[] = $text;
            // A whole code or number ("SKU-12", "1045") is a word too.
            array_push( $words, ...( preg_split(
                '/[^\\p{L}\\p{N}]+/u',
                $text,
                -1,
                PREG_SPLIT_NO_EMPTY
            ) ?: array() ) );
        }
        $worst = 0;
        foreach ( $terms as $term ) {
            $best = 4;
            $plain = self::plain( $term );
            foreach ( $words as $word ) {
                $folded = self::plain( $word );
                $rank = ( $word === $term ? 0 : (( $folded === $plain ? 1 : (( str_starts_with( $word, $term ) ? 2 : (( str_starts_with( $folded, $plain ) ? 3 : 4 )) )) )) );
                $best = min( $best, $rank );
                if ( $best === 0 ) {
                    break;
                }
            }
            $worst = max( $worst, $best );
        }
        return $worst;
    }

    /** The rows best matching first (rank()); rows of the same rank keep the order the source gave them. */
    private static function ranked( array $rows, string $query, callable $texts ) : array {
        $keyed = array();
        foreach ( array_values( $rows ) as $i => $row ) {
            $keyed[] = array(self::rank( $query, ...array_map( 'strval', $texts( $row ) ) ), $i, $row);
        }
        usort( $keyed, static fn( $a, $b ) => ( $a[0] <=> $b[0] ?: $a[1] <=> $b[1] ) );
        return array_column( $keyed, 2 );
    }

    /** Legacy WooCommerce ignores meta_query for orders; HPOS supports it. */
    private static function tracking_orders( string $query ) : array {
        if ( \Automattic\WooCommerce\Utilities\OrderUtil::custom_orders_table_usage_is_enabled() ) {
            return wc_get_orders( array(
                'type'       => 'shop_order',
                'limit'      => 12,
                'return'     => 'objects',
                'meta_query' => array(array(
                    'key'     => '_storesuit_shipments',
                    'value'   => $query,
                    'compare' => 'LIKE',
                )),
            ) );
        }
        global $wpdb;
        $ids = $wpdb->get_col( $wpdb->prepare( "SELECT pm.post_id FROM {$wpdb->postmeta} pm INNER JOIN {$wpdb->posts} p ON p.ID=pm.post_id WHERE pm.meta_key=%s AND pm.meta_value LIKE %s AND p.post_type='shop_order' AND p.post_status NOT IN ('trash','auto-draft') ORDER BY pm.meta_id DESC LIMIT 20", '_storesuit_shipments', '%' . $wpdb->esc_like( $query ) . '%' ) );
        return array_values( array_filter( array_map( 'wc_get_order', array_map( 'intval', $ids ) ), static fn( $order ) => $order instanceof \WC_Order ) );
    }

    public static function read( array $data ) : array {
        Store::require_cap( 'storesuit_orders' );
        $query = trim( Store::text( $data, 'search' ) );
        if ( mb_strlen( $query ) < 2 ) {
            return array(
                'query'  => $query,
                'groups' => array(),
                'total'  => 0,
            );
        }
        if ( mb_strlen( $query ) > 80 ) {
            throw new \InvalidArgumentException(I18n::t( 'Search with 80 characters or fewer.' ));
        }
        $groups = array();
        $seen_orders = array();
        $order_rows = array();
        // Order numbers are shown with a leading #. Keep a product's literal SKU query intact in the other groups.
        $order_query = ( str_starts_with( $query, '#' ) ? trim( substr( $query, 1 ) ) : $query );
        if ( $order_query === '' ) {
            $order_query = $query;
        }
        if ( get_option( 'storesuit_order_index_ready' ) === '1' ) {
            $found = OrderIndex::query( array(
                'search' => $order_query,
                'page'   => 1,
            ) );
            $channel_labels = array(
                'web'       => 'Web store',
                'pos'       => 'Store / POS',
                'instagram' => 'Instagram',
                'whatsapp'  => 'WhatsApp',
                'facebook'  => 'Facebook',
                'phone'     => 'Phone',
                'b2b'       => 'B2B',
                'other'     => 'Other',
            ) + Orders::MARKETS;
            foreach ( array_slice( self::ranked( $found['orders'], $order_query, static fn( $o ) => array($o['number'] ?? '', $o['name'] ?? '') ), 0, 6 ) as $order ) {
                $seen_orders[(int) $order['id']] = true;
                $channel = $channel_labels[(string) $order['channel']] ?? (string) $order['channel'];
                $order_rows[] = self::result(
                    'order',
                    (int) $order['id'],
                    I18n::format( 'Order #%s', $order['number'] ),
                    trim( (( $order['name'] ?: I18n::t( 'Guest' ) )) . ' · ' . I18n::t( 'Sales channel' ) . ': ' . I18n::t( $channel ) ),
                    'storesuit-orders&order=' . (int) $order['id']
                );
            }
        }
        if ( mb_strlen( $query ) >= 3 ) {
            $tracking_orders = self::tracking_orders( $query );
            foreach ( $tracking_orders as $order ) {
                if ( isset( $seen_orders[$order->get_id()] ) ) {
                    continue;
                }
                $tracking = '';
                foreach ( (array) $order->get_meta( '_storesuit_shipments' ) as $shipment ) {
                    if ( stripos( (string) ($shipment['tracking'] ?? ''), $query ) !== false ) {
                        $tracking = (string) $shipment['tracking'];
                        break;
                    }
                }
                if ( $tracking === '' ) {
                    continue;
                }
                $seen_orders[$order->get_id()] = true;
                $order_rows[] = self::result(
                    'tracking',
                    $order->get_id(),
                    I18n::format( 'Tracking %s', $tracking ),
                    I18n::format( 'Order #%s', $order->get_order_number() ),
                    'storesuit-orders&order=' . $order->get_id()
                );
                if ( count( $order_rows ) >= 6 ) {
                    break;
                }
            }
        }
        if ( $order_rows ) {
            $groups[] = array(
                'key'   => 'orders',
                'label' => I18n::t( 'Orders and tracking' ),
                'items' => $order_rows,
            );
        }
        $product_rows = array();
        $products = Products::search( array(
            'search' => $query,
            'page'   => 1,
        ) );
        foreach ( array_slice( self::ranked( $products['rows'], $query, static fn( $p ) => array($p['name'] ?? '', $p['sku'] ?? '', $p['barcode'] ?? '') ), 0, 6 ) as $product ) {
            $code = ( $product['sku'] ?: (( $product['barcode'] ?: '#' . $product['id'] )) );
            // Without product access: the orders with this product code; the paid build opens a new sale with it.
            $find = 'storesuit-orders&search=' . rawurlencode( $code );
            $url = ( current_user_can( 'manage_woocommerce' ) ? 'storesuit-products&id=' . (int) $product['id'] : $find );
            // The record number is no product code a merchant could type or print: say there is none instead of "Product code: #47".
            $product_rows[] = self::result(
                'product',
                (int) $product['id'],
                (string) $product['name'],
                ( (( $product['sku'] ?: $product['barcode'] )) ? I18n::format( 'Product code: %s', $code ) : I18n::t( 'No product code' ) ),
                $url
            );
        }
        if ( $product_rows ) {
            $groups[] = array(
                'key'   => 'products',
                'label' => I18n::t( 'Products, SKU, and barcode' ),
                'items' => $product_rows,
            );
        }
        $customer_rows = array();
        foreach ( array_slice( self::ranked( Customers::search( array(
            'search' => $query,
        ) ), $query, static fn( $c ) => array($c['name'] ?? '', $c['email'] ?? '', $c['phone'] ?? '') ), 0, 6 ) as $customer ) {
            $lookup = ( $customer['phone'] ?: (( $customer['email'] ?: $customer['name'] )) );
            $url = ( current_user_can( 'manage_woocommerce' ) ? 'storesuit-customers&id=' . (int) $customer['id'] : 'storesuit-orders&search=' . rawurlencode( $lookup ) );
            $customer_rows[] = self::result(
                'customer',
                (int) $customer['id'],
                (string) $customer['name'],
                implode( ' · ', array_filter( array($customer['phone'], $customer['email']) ) ),
                $url
            );
        }
        if ( $customer_rows ) {
            $groups[] = array(
                'key'   => 'customers',
                'label' => I18n::t( 'Customers' ),
                'items' => $customer_rows,
            );
        }
        return array(
            'query'  => $query,
            'groups' => $groups,
            'total'  => array_sum( array_map( static fn( $group ) => count( $group['items'] ), $groups ) ),
        );
    }

}