<?php
namespace Dudlewebs\WPMCS;

defined('ABSPATH') || exit;

class Db {
    private static $instance = null;
    private string $assets_url;
    private string $version;
    private string $token;


    /**
     * Admin constructor.
     * @since 1.0.0
     */
    public function __construct() {
        $this->assets_url = WPMCS_ASSETS_URL;
        $this->version    = WPMCS_VERSION;
        $this->token      = WPMCS_TOKEN;
    }

    /**
     * Get table name with correct DB prefix (multisite-aware)
     *
     * @param int|null $blog_id Optional. Blog ID for multisite.
     * @return string
     */
    public static function get_table_name( $blog_id = null ) {
        global $wpdb;
        $prefix = is_multisite() ? $wpdb->get_blog_prefix( $blog_id ?? get_current_blog_id() ) : $wpdb->prefix;
        return $prefix . WPMCS_ITEM_TABLE;
    }

    /**
     * Create Database Table
     * 
     */
    public function create_table() {
        global $wpdb;

        require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );

        $table_name = self::get_table_name();
        $queries = array();
        $charset_collate = $wpdb->get_charset_collate();
        if($wpdb->get_var("SHOW TABLES LIKE '$table_name'") != $table_name) {
            $queries[] = "
                CREATE TABLE {$table_name} (
                id BIGINT(20) NOT NULL AUTO_INCREMENT,
                provider varchar(18) NOT NULL,
                region varchar(255) NOT NULL,
                storage varchar(255) NOT NULL,
                source_id bigint(20) NOT NULL,
                source_path varchar(1024) NOT NULL,
                source_type varchar(18) NOT NULL,
                url varchar(1024) NOT NULL,
                `key` varchar(1024) NOT NULL,
                is_private tinyint(1) NOT NULL DEFAULT 0,
                extra longtext DEFAULT NULL,
                PRIMARY KEY (id),
                UNIQUE KEY uidx_url (url(190), id),
                UNIQUE KEY uidx_key (`key`(190), id),
                UNIQUE KEY uidx_source_path (source_path(190), id)
            ) $charset_collate;";
        } 
        dbDelta( $queries );
    }

    /**
     * Create tables across all sites (on activation)
     */
    public static function handle_tables($network_wide = false) {
        // If network-wide activation, create tables for all sites in multisite
        if (is_multisite() && $network_wide) {
            $sites = get_sites(['number' => 1000, 'fields' => 'ids']); // Adjust number as needed
            // If no sites found, return early
            if (is_wp_error($sites) || !is_array($sites) || empty($sites)) {
                return;
            }
            
            // Create table for each site in multisite
            foreach ($sites as $site_id) {
                switch_to_blog($site_id);
                self::instance()->create_table();
                restore_current_blog();
            }
        } else {
            self::instance()->create_table();
        }
    }

    /**
     * Database Upgrade 
     * @since 1.0.0
     */
    public function do_database_upgrade() {
        global $wpdb;
        $table_name         = self::get_table_name();
        $current_version    = get_option( $this->token.'_db_version' );

        /**
         * If DB version below 1.0.1
         */
        if (version_compare($current_version, '1.0.1', '<')) {
            $credentials = Utils::get_credentials();
            if (isset($credentials['service']) && $credentials['service'] === 'gcloud') {
                $config = $credentials['config'] ?? null;
                if($config) {
                    $config_json_path = $config['config_json']['path'] ?? null;
                    if (!empty($config_json_path) && file_exists($config_json_path)) {
                        $config_json = file_get_contents($config_json_path);
                        if (!empty($config_json)) {
                            $credentials['config']['config_json'] = $config_json;
                            Utils::update_credentials($credentials);
                            $updated = Utils::update_option('credentials', $credentials, Schema::getConstant('GLOBAL_SETTINGS_KEY'));
                            if ($updated) {
                                unlink($config_json_path);
                            }
                        }
                    }
                }
            }
        }

        update_option( $this->token.'_db_version', WPMCS_DB_VERSION, true );
    }

    /**
     * Ensures only one instance of Class is loaded or can be loaded.
     *
     * @return Db Class instance
     * @since 1.0.0
     * @static
     */
    public static function instance(){
        if (is_null(self::$instance)) {
            self::$instance = new self();
        }
        return self::$instance;
    }
}