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

class WBF_DB {

    public static function install() {
        global $wpdb;
        $charset = $wpdb->get_charset_collate();

        $sql_users = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_users (
            id           BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            username     VARCHAR(60)  NOT NULL UNIQUE,
            email        VARCHAR(100) NOT NULL UNIQUE,
            password     VARCHAR(255) NOT NULL,
            display_name VARCHAR(100) NOT NULL,
            avatar_url   VARCHAR(255) DEFAULT '',
            bio          TEXT DEFAULT '',
            signature    TEXT DEFAULT '',
            role         VARCHAR(20) DEFAULT 'member',
            post_count   INT DEFAULT 0,
            registered   DATETIME DEFAULT CURRENT_TIMESTAMP,
            last_active  DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id)
        ) $charset;";

        $sql_cats = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_categories (
            id           BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            parent_id    BIGINT UNSIGNED DEFAULT 0,
            name         VARCHAR(100) NOT NULL,
            slug         VARCHAR(100) NOT NULL UNIQUE,
            description  TEXT DEFAULT '',
            icon         VARCHAR(50)  DEFAULT 'fas fa-comments',
            sort_order   INT DEFAULT 0,
            thread_count INT DEFAULT 0,
            post_count   INT DEFAULT 0,
            min_role     VARCHAR(20) DEFAULT 'member',
            PRIMARY KEY (id),
            KEY parent_id (parent_id)
        ) $charset;";

        $sql_threads = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_threads (
            id            BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            category_id   BIGINT UNSIGNED NOT NULL,
            user_id       BIGINT UNSIGNED NOT NULL,
            title         VARCHAR(255) NOT NULL,
            slug          VARCHAR(255) NOT NULL,
            content       LONGTEXT NOT NULL,
            status        VARCHAR(20) DEFAULT 'open',
            pinned        TINYINT(1) DEFAULT 0,
            views         INT DEFAULT 0,
            reply_count   INT DEFAULT 0,
            like_count    INT DEFAULT 0,
            created_at    DATETIME DEFAULT CURRENT_TIMESTAMP,
            updated_at    DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
            last_reply_at DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            KEY category_id (category_id)
        ) $charset;";

        $sql_posts = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_posts (
            id         BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            thread_id  BIGINT UNSIGNED NOT NULL,
            user_id    BIGINT UNSIGNED NOT NULL,
            content    LONGTEXT NOT NULL,
            like_count INT DEFAULT 0,
            created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
            updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            KEY thread_id (thread_id)
        ) $charset;";

        $sql_likes = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_likes (
            id          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            user_id     BIGINT UNSIGNED NOT NULL,
            object_id   BIGINT UNSIGNED NOT NULL,
            object_type VARCHAR(20) NOT NULL,
            created_at  DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            UNIQUE KEY unique_like (user_id, object_id, object_type)
        ) $charset;";

        $sql_reports = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_reports (
            id          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            object_id   BIGINT UNSIGNED NOT NULL,
            object_type VARCHAR(20) NOT NULL DEFAULT 'post',
            reporter_id BIGINT UNSIGNED NOT NULL,
            reason      VARCHAR(100) NOT NULL DEFAULT '',
            note        TEXT DEFAULT '',
            status      VARCHAR(20) NOT NULL DEFAULT 'open',
            created_at  DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            KEY object_id (object_id),
            KEY status (status)
        ) $charset;";

        $sql_tags = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_tags (
            id         BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            name       VARCHAR(60)  NOT NULL,
            slug       VARCHAR(60)  NOT NULL UNIQUE,
            use_count  INT DEFAULT 0,
            PRIMARY KEY (id),
            KEY slug (slug)
        ) $charset;";

        $sql_thread_tags = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_thread_tags (
            thread_id  BIGINT UNSIGNED NOT NULL,
            tag_id     BIGINT UNSIGNED NOT NULL,
            PRIMARY KEY (thread_id, tag_id),
            KEY tag_id (tag_id)
        ) $charset;";

        $sql_messages = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_messages (
            id          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            from_id     BIGINT UNSIGNED NOT NULL,
            to_id       BIGINT UNSIGNED NOT NULL,
            content     TEXT NOT NULL,
            is_read     TINYINT(1) DEFAULT 0,
            deleted_by_sender   TINYINT(1) DEFAULT 0,
            deleted_by_receiver TINYINT(1) DEFAULT 0,
            created_at  DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            KEY from_id (from_id),
            KEY to_id (to_id)
        ) $charset;";

        $sql_reactions = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_reactions (
            id          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            user_id     BIGINT UNSIGNED NOT NULL,
            object_id   BIGINT UNSIGNED NOT NULL,
            object_type VARCHAR(20) NOT NULL DEFAULT 'post',
            reaction    VARCHAR(10) NOT NULL,
            created_at  DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            UNIQUE KEY unique_reaction (user_id, object_id, object_type),
            KEY object_id (object_id)
        ) $charset;";

        $sql_remember = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_remember_tokens (
            id         BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            user_id    BIGINT UNSIGNED NOT NULL,
            token      VARCHAR(64) NOT NULL,
            expires_at DATETIME NOT NULL,
            PRIMARY KEY (id),
            UNIQUE KEY token (token),
            KEY user_id (user_id)
        ) $charset;";

        require_once ABSPATH . 'wp-admin/includes/upgrade.php';
        dbDelta( $sql_users );
        dbDelta( $sql_cats );
        dbDelta( $sql_threads );
        dbDelta( $sql_posts );
        dbDelta( $sql_likes );
        dbDelta( $sql_reports );
        dbDelta( $sql_tags );
        dbDelta( $sql_thread_tags );
        dbDelta( $sql_messages );
        dbDelta( $sql_reactions );
        dbDelta( $sql_remember );

        // Live upgrades — add new columns to existing installs
        self::maybe_add_column("{$wpdb->prefix}forum_users",      'signature',  "ALTER TABLE {$wpdb->prefix}forum_users ADD COLUMN signature TEXT DEFAULT '' AFTER bio");
        self::maybe_add_column("{$wpdb->prefix}forum_users",      'ban_reason', "ALTER TABLE {$wpdb->prefix}forum_users ADD COLUMN ban_reason TEXT DEFAULT '' AFTER role");
        self::maybe_add_column("{$wpdb->prefix}forum_categories", 'parent_id', "ALTER TABLE {$wpdb->prefix}forum_categories ADD COLUMN parent_id BIGINT UNSIGNED DEFAULT 0 AFTER id");
        self::maybe_add_column("{$wpdb->prefix}forum_categories", 'min_role',  "ALTER TABLE {$wpdb->prefix}forum_categories ADD COLUMN min_role VARCHAR(20) DEFAULT 'member' AFTER post_count");
        self::maybe_add_column("{$wpdb->prefix}forum_users", 'reset_token',         "ALTER TABLE {$wpdb->prefix}forum_users ADD COLUMN reset_token VARCHAR(64) DEFAULT NULL");
        self::maybe_add_column("{$wpdb->prefix}forum_users", 'reset_token_expires', "ALTER TABLE {$wpdb->prefix}forum_users ADD COLUMN reset_token_expires DATETIME DEFAULT NULL");
        $sql_notifications = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}forum_notifications (
            id          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
            user_id     BIGINT UNSIGNED NOT NULL,
            type        VARCHAR(30) NOT NULL DEFAULT 'reply',
            object_id   BIGINT UNSIGNED NOT NULL,
            actor_id    BIGINT UNSIGNED NOT NULL,
            is_read     TINYINT(1) DEFAULT 0,
            created_at  DATETIME DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY (id),
            KEY user_id (user_id),
            KEY is_read (is_read)
        ) $charset;";

        // Ensure reports + notifications tables exist on existing installs
        dbDelta( $sql_reports );
        dbDelta( $sql_notifications );

        // Default categories
        $count = $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->prefix}forum_categories");
        if ( (int)$count === 0 ) {
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>0,'name'=>'Allgemein',     'slug'=>'allgemein',     'description'=>'Allgemeine Diskussionen','icon'=>'fas fa-home',     'sort_order'=>1]);
            $p1 = $wpdb->insert_id;
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>0,'name'=>'Ankündigungen', 'slug'=>'ankuendigungen','description'=>'Wichtige Neuigkeiten',   'icon'=>'fas fa-bullhorn', 'sort_order'=>2,'min_role'=>'moderator']);
            $p2 = $wpdb->insert_id;
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>0,'name'=>'Support',       'slug'=>'support',       'description'=>'Hilfe & Fragen',         'icon'=>'fas fa-life-ring','sort_order'=>3]);
            $p3 = $wpdb->insert_id;
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>$p1,'name'=>'Introductions',   'slug'=>'introductions',  'description'=>'Stell dich vor!',            'icon'=>'fas fa-user',    'sort_order'=>1]);
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>$p1,'name'=>'Off-Topic',       'slug'=>'off-topic',      'description'=>'Alles außerhalb des Themas', 'icon'=>'fas fa-coffee',  'sort_order'=>2]);
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>$p3,'name'=>'Bug Reports',     'slug'=>'bug-reports',    'description'=>'Fehler melden',              'icon'=>'fas fa-bug',     'sort_order'=>1]);
            $wpdb->insert("{$wpdb->prefix}forum_categories", ['parent_id'=>$p3,'name'=>'Feature Requests','slug'=>'feature-requests','description'=>'Neue Funktionen vorschlagen','icon'=>'fas fa-lightbulb','sort_order'=>2]);
        }
    }

    private static function maybe_add_column( $table, $column, $sql ) {
        global $wpdb;
        $cols = $wpdb->get_col("DESCRIBE {$table}");
        if ( ! in_array($column, $cols) ) {
            $wpdb->query($sql);
        }
    }

    // ── Rollen — delegiert an WBF_Roles ──────────────────────────────────────

    public static function role_level( $role ) { return WBF_Roles::level($role); }
    public static function all_roles()          { return WBF_Roles::labels(); }
    public static function can( $user, $action ){ return WBF_Roles::can($user, $action); }
    public static function can_post_in( $user, $cat ) { return WBF_Roles::can_post_in($user, $cat); }

    // ── Users ─────────────────────────────────────────────────────────────────

    public static function get_user( $id ) {
        global $wpdb;
        return $wpdb->get_row( $wpdb->prepare("SELECT * FROM {$wpdb->prefix}forum_users WHERE id=%d", $id) );
    }

    public static function get_user_by( $field, $value ) {
        global $wpdb;
        $field = sanitize_key($field);
        // Benutzername & E-Mail: Groß-/Kleinschreibung ignorieren (LOWER)
        if ( in_array($field, ['username', 'email']) ) {
            return $wpdb->get_row( $wpdb->prepare(
                "SELECT * FROM {$wpdb->prefix}forum_users WHERE LOWER($field)=LOWER(%s)",
                $value
            ) );
        }
        return $wpdb->get_row( $wpdb->prepare("SELECT * FROM {$wpdb->prefix}forum_users WHERE $field=%s", $value) );
    }

    public static function create_user( $data ) {
        global $wpdb;
        $wpdb->insert("{$wpdb->prefix}forum_users", $data);
        return $wpdb->insert_id;
    }

    public static function update_user( $id, $data ) {
        global $wpdb;
        $wpdb->update("{$wpdb->prefix}forum_users", $data, ['id' => $id]);
    }

    public static function get_all_users( $limit = 100, $offset = 0 ) {
        global $wpdb;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}forum_users ORDER BY registered DESC LIMIT %d OFFSET %d",
            $limit, $offset
        ));
    }

    // ── Categories ────────────────────────────────────────────────────────────

    public static function get_categories_tree() {
        global $wpdb;
        $all = $wpdb->get_results(
            "SELECT c.*,
             (SELECT t.title FROM {$wpdb->prefix}forum_threads t WHERE t.category_id=c.id ORDER BY t.last_reply_at DESC LIMIT 1) as last_thread_title,
             (SELECT t.id    FROM {$wpdb->prefix}forum_threads t WHERE t.category_id=c.id ORDER BY t.last_reply_at DESC LIMIT 1) as last_thread_id,
             (SELECT u.display_name FROM {$wpdb->prefix}forum_threads t
              JOIN {$wpdb->prefix}forum_users u ON u.id=t.user_id
              WHERE t.category_id=c.id ORDER BY t.last_reply_at DESC LIMIT 1) as last_post_author
             FROM {$wpdb->prefix}forum_categories c
             ORDER BY c.parent_id ASC, c.sort_order ASC"
        );
        $by_id = [];
        foreach ($all as $cat) { $cat->children = []; $by_id[$cat->id] = $cat; }
        $tree = [];
        foreach ($by_id as $id => $cat) {
            if ((int)$cat->parent_id === 0) $tree[] = &$by_id[$id];
            elseif (isset($by_id[$cat->parent_id])) $by_id[$cat->parent_id]->children[] = &$by_id[$id];
        }
        return $tree;
    }

    public static function get_categories_flat() {
        global $wpdb;
        return $wpdb->get_results("SELECT * FROM {$wpdb->prefix}forum_categories ORDER BY parent_id ASC, sort_order ASC");
    }

    public static function get_category( $id_or_slug ) {
        global $wpdb;
        if (is_numeric($id_or_slug)) return $wpdb->get_row($wpdb->prepare("SELECT * FROM {$wpdb->prefix}forum_categories WHERE id=%d", $id_or_slug));
        return $wpdb->get_row($wpdb->prepare("SELECT * FROM {$wpdb->prefix}forum_categories WHERE slug=%s", $id_or_slug));
    }

    public static function get_category_breadcrumb( $cat ) {
        $path = [$cat]; $max = 5;
        while ((int)$cat->parent_id > 0 && $max--) {
            $cat = self::get_category((int)$cat->parent_id);
            if (!$cat) break;
            array_unshift($path, $cat);
        }
        return $path;
    }

    public static function get_child_categories( $parent_id ) {
        global $wpdb;
        return $wpdb->get_results($wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}forum_categories WHERE parent_id=%d ORDER BY sort_order ASC", $parent_id
        ));
    }

    // ── Threads ───────────────────────────────────────────────────────────────

    public static function get_threads( $category_id, $page = 1, $per_page = 20, $include_archived = false ) {
        global $wpdb;
        $offset     = ($page - 1) * $per_page;
        $status_sql = $include_archived ? '' : "AND t.status != 'archived'";
        return $wpdb->get_results($wpdb->prepare(
            "SELECT t.*, u.display_name, u.avatar_url, u.username, u.role as author_role
             FROM {$wpdb->prefix}forum_threads t
             JOIN {$wpdb->prefix}forum_users u ON u.id = t.user_id
             WHERE t.category_id = %d $status_sql
             ORDER BY t.pinned DESC, t.last_reply_at DESC
             LIMIT %d OFFSET %d",
            $category_id, $per_page, $offset
        ));
    }

    public static function get_archived_threads( $category_id = 0, $page = 1, $per_page = 20 ) {
        global $wpdb;
        $offset   = ($page - 1) * $per_page;
        $cat_sql  = $category_id ? $wpdb->prepare('AND t.category_id = %d', $category_id) : '';
        return $wpdb->get_results($wpdb->prepare(
            "SELECT t.*, u.display_name, u.avatar_url, u.username, u.role as author_role,
                    c.name as cat_name, c.slug as cat_slug
             FROM {$wpdb->prefix}forum_threads t
             JOIN {$wpdb->prefix}forum_users u ON u.id = t.user_id
             JOIN {$wpdb->prefix}forum_categories c ON c.id = t.category_id
             WHERE t.status = 'archived' $cat_sql
             ORDER BY t.last_reply_at DESC
             LIMIT %d OFFSET %d",
            $per_page, $offset
        ));
    }

    public static function count_archived_threads( $category_id = 0 ) {
        global $wpdb;
        if ( $category_id ) {
            return (int)$wpdb->get_var($wpdb->prepare(
                "SELECT COUNT(*) FROM {$wpdb->prefix}forum_threads WHERE status='archived' AND category_id=%d", $category_id
            ));
        }
        return (int)$wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->prefix}forum_threads WHERE status='archived'");
    }

    public static function count_threads( $category_id ) {
        global $wpdb;
        return (int)$wpdb->get_var($wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->prefix}forum_threads WHERE category_id=%d AND status != 'archived'",
            $category_id
        ));
    }

    public static function move_thread( $thread_id, $new_category_id ) {
        global $wpdb;
        $thread = self::get_thread($thread_id);
        if ( ! $thread ) return false;
        $old_cat = (int) $thread->category_id;
        $new_cat = (int) $new_category_id;
        if ( $old_cat === $new_cat ) return false;

        $wpdb->update( "{$wpdb->prefix}forum_threads", ['category_id' => $new_cat], ['id' => $thread_id] );
        // Adjust thread counts (don't count archived)
        if ( $thread->status !== 'archived' ) {
            $wpdb->query($wpdb->prepare(
                "UPDATE {$wpdb->prefix}forum_categories SET thread_count=GREATEST(thread_count-1,0) WHERE id=%d", $old_cat
            ));
            $wpdb->query($wpdb->prepare(
                "UPDATE {$wpdb->prefix}forum_categories SET thread_count=thread_count+1 WHERE id=%d", $new_cat
            ));
        }
        // Move post_count contribution too
        $post_count = (int)$wpdb->get_var($wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->prefix}forum_posts WHERE thread_id=%d", $thread_id
        ));
        if ( $post_count > 0 ) {
            $wpdb->query($wpdb->prepare(
                "UPDATE {$wpdb->prefix}forum_categories SET post_count=GREATEST(post_count-%d,0) WHERE id=%d", $post_count, $old_cat
            ));
            $wpdb->query($wpdb->prepare(
                "UPDATE {$wpdb->prefix}forum_categories SET post_count=post_count+%d WHERE id=%d", $post_count, $new_cat
            ));
        }
        return true;
    }

    public static function get_thread( $id ) {
        global $wpdb;
        return $wpdb->get_row($wpdb->prepare(
            "SELECT t.*, u.display_name, u.avatar_url, u.username, u.signature,
                    u.post_count as author_posts, u.registered as author_registered, u.role as author_role
             FROM {$wpdb->prefix}forum_threads t
             JOIN {$wpdb->prefix}forum_users u ON u.id = t.user_id
             WHERE t.id = %d", $id
        ));
    }

    public static function create_thread( $data ) {
        global $wpdb;
        $wpdb->insert("{$wpdb->prefix}forum_threads", $data);
        $id = $wpdb->insert_id;
        $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_categories SET thread_count=thread_count+1 WHERE id=%d", $data['category_id']));
        $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_users SET post_count=post_count+1 WHERE id=%d", $data['user_id']));
        return $id;
    }

    public static function delete_thread( $id ) {
        global $wpdb;
        $thread = self::get_thread($id);
        if (!$thread) return;
        // Clean up tag associations and decrement use_counts
        $tag_ids = $wpdb->get_col( $wpdb->prepare(
            "SELECT tag_id FROM {$wpdb->prefix}forum_thread_tags WHERE thread_id=%d", $id
        ) );
        $wpdb->delete( "{$wpdb->prefix}forum_thread_tags", ['thread_id' => $id] );
        if ( $tag_ids ) {
            foreach ( $tag_ids as $tid ) {
                $wpdb->query( $wpdb->prepare(
                    "UPDATE {$wpdb->prefix}forum_tags SET use_count=GREATEST(use_count-1,0) WHERE id=%d", (int)$tid
                ) );
            }
        }
        $wpdb->delete("{$wpdb->prefix}forum_posts", ['thread_id' => $id]);
        $wpdb->delete("{$wpdb->prefix}forum_threads", ['id' => $id]);
        if ( $thread->status !== 'archived' ) {
            $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_categories SET thread_count=GREATEST(thread_count-1,0) WHERE id=%d", $thread->category_id));
        }
    }

    public static function update_thread( $id, $data ) {
        global $wpdb;
        $wpdb->update("{$wpdb->prefix}forum_threads", $data, ['id' => $id]);
    }

    // ── Posts ─────────────────────────────────────────────────────────────────

    public static function get_posts( $thread_id, $page = 1, $per_page = 15 ) {
        global $wpdb;
        $offset = ($page - 1) * $per_page;
        return $wpdb->get_results($wpdb->prepare(
            "SELECT p.*, u.display_name, u.avatar_url, u.username, u.signature,
                    u.post_count as author_posts, u.role as author_role, u.registered as author_registered
             FROM {$wpdb->prefix}forum_posts p
             JOIN {$wpdb->prefix}forum_users u ON u.id = p.user_id
             WHERE p.thread_id = %d
             ORDER BY p.created_at ASC
             LIMIT %d OFFSET %d",
            $thread_id, $per_page, $offset
        ));
    }

    public static function count_posts( $thread_id ) {
        global $wpdb;
        return (int)$wpdb->get_var($wpdb->prepare("SELECT COUNT(*) FROM {$wpdb->prefix}forum_posts WHERE thread_id=%d", $thread_id));
    }

    public static function create_post( $data ) {
        global $wpdb;
        $wpdb->insert("{$wpdb->prefix}forum_posts", $data);
        $id = $wpdb->insert_id;
        $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_threads SET reply_count=reply_count+1, last_reply_at=NOW() WHERE id=%d", $data['thread_id']));
        $thread = $wpdb->get_row($wpdb->prepare("SELECT category_id FROM {$wpdb->prefix}forum_threads WHERE id=%d", $data['thread_id']));
        if ($thread) $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_categories SET post_count=post_count+1 WHERE id=%d", $thread->category_id));
        $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_users SET post_count=post_count+1 WHERE id=%d", $data['user_id']));
        return $id;
    }

    public static function delete_post( $id ) {
        global $wpdb;
        $post = $wpdb->get_row($wpdb->prepare("SELECT * FROM {$wpdb->prefix}forum_posts WHERE id=%d", $id));
        if (!$post) return;
        $wpdb->delete("{$wpdb->prefix}forum_posts", ['id' => $id]);
        $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_threads SET reply_count=GREATEST(reply_count-1,0) WHERE id=%d", $post->thread_id));
        $wpdb->query($wpdb->prepare("UPDATE {$wpdb->prefix}forum_users SET post_count=GREATEST(post_count-1,0) WHERE id=%d", $post->user_id));
    }

    // ── Likes ─────────────────────────────────────────────────────────────────

    public static function has_liked( $user_id, $object_id, $type ) {
        global $wpdb;
        return (bool)$wpdb->get_var($wpdb->prepare(
            "SELECT id FROM {$wpdb->prefix}forum_likes WHERE user_id=%d AND object_id=%d AND object_type=%s",
            $user_id, $object_id, $type
        ));
    }

    public static function toggle_like( $user_id, $object_id, $type ) {
        global $wpdb;
        $map = ['thread'=>"{$wpdb->prefix}forum_threads",'post'=>"{$wpdb->prefix}forum_posts"];
        if (self::has_liked($user_id, $object_id, $type)) {
            $wpdb->delete("{$wpdb->prefix}forum_likes", ['user_id'=>$user_id,'object_id'=>$object_id,'object_type'=>$type]);
            if (isset($map[$type])) $wpdb->query($wpdb->prepare("UPDATE {$map[$type]} SET like_count=GREATEST(like_count-1,0) WHERE id=%d",$object_id));
            return 'unliked';
        } else {
            $wpdb->insert("{$wpdb->prefix}forum_likes", ['user_id'=>$user_id,'object_id'=>$object_id,'object_type'=>$type]);
            if (isset($map[$type])) $wpdb->query($wpdb->prepare("UPDATE {$map[$type]} SET like_count=like_count+1 WHERE id=%d",$object_id));
            return 'liked';
        }
    }

    public static function get_like_count( $object_id, $type ) {
        global $wpdb;
        $map = ['thread'=>"{$wpdb->prefix}forum_threads",'post'=>"{$wpdb->prefix}forum_posts"];
        if (!isset($map[$type])) return 0;
        return (int)$wpdb->get_var($wpdb->prepare("SELECT like_count FROM {$map[$type]} WHERE id=%d",$object_id));
    }

    // ── Stats ─────────────────────────────────────────────────────────────────

    public static function get_recent_threads( $limit = 5 ) {
        global $wpdb;
        return $wpdb->get_results($wpdb->prepare(
            "SELECT t.id, t.title, t.created_at, u.display_name, c.name as cat_name, c.slug as cat_slug
             FROM {$wpdb->prefix}forum_threads t
             JOIN {$wpdb->prefix}forum_users u ON u.id = t.user_id
             JOIN {$wpdb->prefix}forum_categories c ON c.id = t.category_id
             AND t.status != 'archived' ORDER BY t.created_at DESC LIMIT %d", $limit
        ));
    }

    public static function get_stats() {
        global $wpdb;
        return [
            'threads' => $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->prefix}forum_threads WHERE status != 'archived'"),
            'posts'   => $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->prefix}forum_posts"),
            'members' => $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->prefix}forum_users"),
            'newest'  => $wpdb->get_var("SELECT display_name FROM {$wpdb->prefix}forum_users ORDER BY registered DESC LIMIT 1"),
        ];
    }

    // ── Reports ───────────────────────────────────────────────────────────────

    public static function create_report( $data ) {
        global $wpdb;
        $wpdb->insert("{$wpdb->prefix}forum_reports", $data);
        return $wpdb->insert_id;
    }

    public static function has_reported( $reporter_id, $object_id, $type = 'post' ) {
        global $wpdb;
        return (bool)$wpdb->get_var($wpdb->prepare(
            "SELECT id FROM {$wpdb->prefix}forum_reports WHERE reporter_id=%d AND object_id=%d AND object_type=%s AND status='open'",
            $reporter_id, $object_id, $type
        ));
    }

    public static function get_reports( $status = 'open', $limit = 50 ) {
        global $wpdb;
        $sql = "SELECT r.*,
                    rep.display_name AS reporter_name, rep.username AS reporter_username,
                    p.content AS post_content, p.thread_id AS thread_id,
                    t.title AS thread_title
             FROM {$wpdb->prefix}forum_reports r
             LEFT JOIN {$wpdb->prefix}forum_users rep ON rep.id = r.reporter_id
             LEFT JOIN {$wpdb->prefix}forum_posts p   ON p.id  = r.object_id AND r.object_type = 'post'
             LEFT JOIN {$wpdb->prefix}forum_threads t ON t.id  = p.thread_id";
        if ( $status !== 'all' ) {
            $sql .= $wpdb->prepare( " WHERE r.status = %s", $status );
        }
        $sql .= $wpdb->prepare( " ORDER BY r.created_at DESC LIMIT %d", $limit );
        return $wpdb->get_results( $sql );
    }

    public static function update_report( $id, $status ) {
        global $wpdb;
        $wpdb->update("{$wpdb->prefix}forum_reports", ['status' => $status], ['id' => $id]);
    }

    public static function get_user_posts( $user_id, $limit = 30 ) {
        global $wpdb;
        // UNION: Thread-Erstbeiträge (forum_threads) + Antworten (forum_posts)
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT 'thread' AS entry_type,
                    t.id AS id, t.content, t.created_at, t.like_count,
                    t.id AS thread_id, t.title AS thread_title,
                    c.name AS cat_name
             FROM {$wpdb->prefix}forum_threads t
             JOIN {$wpdb->prefix}forum_categories c ON c.id = t.category_id
             WHERE t.user_id = %d
             UNION ALL
             SELECT 'post' AS entry_type,
                    p.id AS id, p.content, p.created_at, p.like_count,
                    t.id AS thread_id, t.title AS thread_title,
                    c.name AS cat_name
             FROM {$wpdb->prefix}forum_posts p
             JOIN {$wpdb->prefix}forum_threads t ON t.id = p.thread_id
             JOIN {$wpdb->prefix}forum_categories c ON c.id = t.category_id
             WHERE p.user_id = %d
             ORDER BY created_at DESC
             LIMIT %d",
            $user_id, $user_id, $limit
        ) );
    }

        // ── Thread-Teilnehmer (für Benachrichtigungen) ───────────────────────────

    public static function get_thread_participants( $thread_id ) {
        global $wpdb;
        // Thread-Ersteller + alle die geantwortet haben (ohne Duplikate)
        return $wpdb->get_col( $wpdb->prepare(
            "SELECT DISTINCT user_id FROM (
                SELECT user_id FROM {$wpdb->prefix}forum_threads WHERE id = %d
                UNION
                SELECT user_id FROM {$wpdb->prefix}forum_posts WHERE thread_id = %d
            ) AS participants",
            $thread_id, $thread_id
        ) );
    }

    // ── Suche ─────────────────────────────────────────────────────────────────

    public static function search( $query, $limit = 30 ) {
        global $wpdb;
        $like = '%' . $wpdb->esc_like( $query ) . '%';
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT 'thread' AS result_type,
                    t.id, t.title, t.content, t.created_at, t.reply_count,
                    u.display_name, u.avatar_url, u.role AS author_role,
                    c.name AS cat_name, c.slug AS cat_slug
             FROM {$wpdb->prefix}forum_threads t
             JOIN {$wpdb->prefix}forum_users u ON u.id = t.user_id
             JOIN {$wpdb->prefix}forum_categories c ON c.id = t.category_id
             WHERE (t.title LIKE %s OR t.content LIKE %s) AND t.status != 'archived'
             UNION ALL
             SELECT 'post' AS result_type,
                    p.id, t.title, p.content, p.created_at, 0 AS reply_count,
                    u.display_name, u.avatar_url, u.role AS author_role,
                    c.name AS cat_name, c.slug AS cat_slug
             FROM {$wpdb->prefix}forum_posts p
             JOIN {$wpdb->prefix}forum_threads t ON t.id = p.thread_id
             JOIN {$wpdb->prefix}forum_users u ON u.id = p.user_id
             JOIN {$wpdb->prefix}forum_categories c ON c.id = t.category_id
             WHERE p.content LIKE %s AND t.status != 'archived'
             ORDER BY created_at DESC
             LIMIT %d",
            $like, $like, $like, $limit
        ) );
    }

    // ── Benachrichtigungen ────────────────────────────────────────────────────

    public static function create_notification( $user_id, $type, $object_id, $actor_id ) {
        global $wpdb;
        // Keine doppelten ungelesenen Benachrichtigungen
        $exists = $wpdb->get_var( $wpdb->prepare(
            "SELECT id FROM {$wpdb->prefix}forum_notifications
             WHERE user_id=%d AND type=%s AND object_id=%d AND actor_id=%d AND is_read=0",
            $user_id, $type, $object_id, $actor_id
        ) );
        if ( $exists ) return;
        // Nicht sich selbst benachrichtigen
        if ( (int)$user_id === (int)$actor_id ) return;
        $wpdb->insert( "{$wpdb->prefix}forum_notifications", [
            'user_id'   => $user_id,
            'type'      => $type,
            'object_id' => $object_id,
            'actor_id'  => $actor_id,
        ] );
    }

    public static function get_notifications( $user_id, $limit = 20 ) {
        global $wpdb;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT n.*,
                    u.display_name AS actor_name, u.avatar_url AS actor_avatar,
                    t.title AS thread_title, t.id AS thread_id
             FROM {$wpdb->prefix}forum_notifications n
             JOIN {$wpdb->prefix}forum_users u ON u.id = n.actor_id
             LEFT JOIN {$wpdb->prefix}forum_threads t ON t.id = n.object_id
             WHERE n.user_id = %d
             ORDER BY n.created_at DESC
             LIMIT %d",
            $user_id, $limit
        ) );
    }

    public static function count_unread_notifications( $user_id ) {
        global $wpdb;
        $table = "{$wpdb->prefix}forum_notifications";
        if ( $wpdb->get_var("SHOW TABLES LIKE '$table'") !== $table ) return 0;
        return (int) $wpdb->get_var( $wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->prefix}forum_notifications WHERE user_id=%d AND is_read=0",
            $user_id
        ) );
    }

    public static function mark_notifications_read( $user_id ) {
        global $wpdb;
        $wpdb->update(
            "{$wpdb->prefix}forum_notifications",
            ['is_read' => 1],
            ['user_id' => $user_id, 'is_read' => 0]
        );
    }

    public static function count_open_reports() {
        global $wpdb;
        // Tabelle existiert evtl. noch nicht auf bestehenden Installs → erst prüfen
        $table = "{$wpdb->prefix}forum_reports";
        if ( $wpdb->get_var("SHOW TABLES LIKE '$table'") !== $table ) {
            return 0;
        }
        return (int)$wpdb->get_var("SELECT COUNT(*) FROM $table WHERE status='open'");
    }

    // ── Tags ──────────────────────────────────────────────────────────────────

    /**
     * Tags für einen Thread speichern.
     * $raw_tags = komma- oder leerzeichen-getrennte Zeichenkette, z.B. "php wordpress #cms"
     */
    public static function sync_thread_tags( $thread_id, $raw_tags ) {
        global $wpdb;
        $thread_id = (int) $thread_id;

        // Bestehende Verknüpfungen löschen
        $old_ids = $wpdb->get_col( $wpdb->prepare(
            "SELECT tag_id FROM {$wpdb->prefix}forum_thread_tags WHERE thread_id=%d", $thread_id
        ) );
        $wpdb->delete( "{$wpdb->prefix}forum_thread_tags", ['thread_id' => $thread_id] );
        // use_count für entfernte Tags dekrementieren
        if ( $old_ids ) {
            $placeholders = implode(',', array_fill(0, count($old_ids), '%d'));
            $wpdb->query( $wpdb->prepare(
                "UPDATE {$wpdb->prefix}forum_tags SET use_count = GREATEST(use_count-1,0) WHERE id IN ($placeholders)",
                ...$old_ids
            ) );
        }

        // Tags parsen
        $names = self::parse_tag_string( $raw_tags );
        if ( empty($names) ) return;

        foreach ( $names as $name ) {
            $slug = sanitize_title( $name );
            if ( ! $slug ) continue;

            // Upsert Tag
            $tag = $wpdb->get_row( $wpdb->prepare(
                "SELECT id FROM {$wpdb->prefix}forum_tags WHERE slug=%s", $slug
            ) );
            if ( $tag ) {
                $tag_id = (int) $tag->id;
                $wpdb->query( $wpdb->prepare(
                    "UPDATE {$wpdb->prefix}forum_tags SET use_count=use_count+1 WHERE id=%d", $tag_id
                ) );
            } else {
                $wpdb->insert( "{$wpdb->prefix}forum_tags", [
                    'name'      => $name,
                    'slug'      => $slug,
                    'use_count' => 1,
                ] );
                $tag_id = $wpdb->insert_id;
            }

            // Pivot
            $wpdb->replace( "{$wpdb->prefix}forum_thread_tags", [
                'thread_id' => $thread_id,
                'tag_id'    => $tag_id,
            ] );
        }
    }

    public static function parse_tag_string( $raw ) {
        // Strip # prefix, split by comma / space / semicolon
        $raw   = strip_tags( $raw );
        $raw   = str_replace('#', '', $raw);
        $parts = preg_split('/[\s,;]+/', $raw, -1, PREG_SPLIT_NO_EMPTY);
        $names = [];
        foreach ( $parts as $p ) {
            $p = mb_strtolower( trim($p) );
            if ( mb_strlen($p) >= 2 && mb_strlen($p) <= 30 ) {
                $names[] = $p;
            }
        }
        return array_unique( array_slice($names, 0, 10) ); // max 10 Tags pro Thread
    }

    /** Tags eines Threads laden */
    public static function get_thread_tags( $thread_id ) {
        global $wpdb;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT t.* FROM {$wpdb->prefix}forum_tags t
             INNER JOIN {$wpdb->prefix}forum_thread_tags tt ON tt.tag_id = t.id
             WHERE tt.thread_id = %d
             ORDER BY t.name ASC",
            $thread_id
        ) );
    }

    /** Threads nach Tag-Slug laden */
    public static function get_threads_by_tag( $slug, $page = 1, $per_page = 20 ) {
        global $wpdb;
        $offset = ($page - 1) * $per_page;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT t.*, u.display_name, u.avatar_url, u.role AS author_role,
                    c.name AS cat_name, c.slug AS cat_slug
             FROM {$wpdb->prefix}forum_threads t
             INNER JOIN {$wpdb->prefix}forum_thread_tags tt ON tt.thread_id = t.id
             INNER JOIN {$wpdb->prefix}forum_tags tg        ON tg.id = tt.tag_id
             JOIN {$wpdb->prefix}forum_users u              ON u.id = t.user_id
             JOIN {$wpdb->prefix}forum_categories c         ON c.id = t.category_id
             WHERE tg.slug = %s AND t.status != 'archived'
             ORDER BY t.last_reply_at DESC
             LIMIT %d OFFSET %d",
            $slug, $per_page, $offset
        ) );
    }

    public static function count_threads_by_tag( $slug ) {
        global $wpdb;
        return (int) $wpdb->get_var( $wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->prefix}forum_threads t
             INNER JOIN {$wpdb->prefix}forum_thread_tags tt ON tt.thread_id = t.id
             INNER JOIN {$wpdb->prefix}forum_tags tg        ON tg.id = tt.tag_id
             WHERE tg.slug = %s AND t.status != 'archived'",
            $slug
        ) );
    }

    /** Tag-Objekt per Slug */
    public static function get_tag( $slug ) {
        global $wpdb;
        return $wpdb->get_row( $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}forum_tags WHERE slug=%s", $slug
        ) );
    }

    /** Top-Tags nach Nutzungshäufigkeit */
    public static function get_popular_tags( $limit = 30 ) {
        global $wpdb;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}forum_tags WHERE use_count > 0 ORDER BY use_count DESC LIMIT %d",
            $limit
        ) );
    }

    /** Autocomplete: Tags die mit $q beginnen */
    public static function suggest_tags( $q, $limit = 8 ) {
        global $wpdb;
        $like = $wpdb->esc_like( strtolower($q) ) . '%';
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT name, slug, use_count FROM {$wpdb->prefix}forum_tags WHERE slug LIKE %s ORDER BY use_count DESC LIMIT %d",
            $like, $limit
        ) );
    }


    // ── Online-Status ──────────────────────────────────────────────────────────

    /** Letztes Aktivitätsdatum des Users aktualisieren */
    public static function touch_last_active( $user_id ) {
        global $wpdb;
        $wpdb->query( $wpdb->prepare(
            "UPDATE {$wpdb->prefix}forum_users SET last_active=NOW() WHERE id=%d", (int)$user_id
        ) );
    }

    /** User die in den letzten $minutes Minuten aktiv waren */
    public static function get_online_users( $minutes = 15 ) {
        global $wpdb;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT id, username, display_name, avatar_url, role
             FROM {$wpdb->prefix}forum_users
             WHERE last_active >= DATE_SUB(NOW(), INTERVAL %d MINUTE)
             ORDER BY last_active DESC
             LIMIT 50",
            $minutes
        ) );
    }

    public static function is_online( $user_id, $minutes = 15 ) {
        global $wpdb;
        return (bool)$wpdb->get_var( $wpdb->prepare(
            "SELECT id FROM {$wpdb->prefix}forum_users
             WHERE id=%d AND last_active >= DATE_SUB(NOW(), INTERVAL %d MINUTE)",
            $user_id, $minutes
        ) );
    }

    // ── Reaktionen ────────────────────────────────────────────────────────────

    public static function set_reaction( $user_id, $object_id, $object_type, $reaction ) {
        global $wpdb;
        $allowed = ['👍','❤️','😂','😮','😢','😡'];
        if ( ! in_array($reaction, $allowed, true) ) return false;

        $existing = $wpdb->get_row( $wpdb->prepare(
            "SELECT reaction FROM {$wpdb->prefix}forum_reactions
             WHERE user_id=%d AND object_id=%d AND object_type=%s",
            $user_id, $object_id, $object_type
        ) );

        if ( $existing && $existing->reaction === $reaction ) {
            // Same reaction → remove (toggle off)
            $wpdb->delete( "{$wpdb->prefix}forum_reactions", [
                'user_id' => $user_id, 'object_id' => $object_id, 'object_type' => $object_type
            ] );
            return 'removed';
        }
        // Insert or replace
        $wpdb->replace( "{$wpdb->prefix}forum_reactions", [
            'user_id'     => $user_id,
            'object_id'   => $object_id,
            'object_type' => $object_type,
            'reaction'    => $reaction,
        ] );
        return 'added';
    }

    /** Reaktionen für ein Objekt — [emoji => count] + user's own reaction */
    public static function get_reactions( $object_id, $object_type, $user_id = 0 ) {
        global $wpdb;
        $rows = $wpdb->get_results( $wpdb->prepare(
            "SELECT reaction, COUNT(*) as cnt
             FROM {$wpdb->prefix}forum_reactions
             WHERE object_id=%d AND object_type=%s
             GROUP BY reaction",
            $object_id, $object_type
        ) );
        $counts = [];
        foreach ( $rows as $r ) $counts[$r->reaction] = (int)$r->cnt;

        $my = '';
        if ( $user_id ) {
            $row = $wpdb->get_row( $wpdb->prepare(
                "SELECT reaction FROM {$wpdb->prefix}forum_reactions
                 WHERE user_id=%d AND object_id=%d AND object_type=%s",
                $user_id, $object_id, $object_type
            ) );
            if ($row) $my = $row->reaction;
        }
        return ['counts' => $counts, 'mine' => $my];
    }

    // ── Private Nachrichten ───────────────────────────────────────────────────

    public static function send_message( $from_id, $to_id, $content ) {
        global $wpdb;
        $wpdb->insert( "{$wpdb->prefix}forum_messages", [
            'from_id'   => (int)$from_id,
            'to_id'     => (int)$to_id,
            'content'   => mb_substr(strip_tags($content), 0, 2000),
            'is_read'   => 0,
        ] );
        return $wpdb->insert_id;
    }

    /** Alle Konversationspartner des Users */
    public static function get_inbox( $user_id ) {
        global $wpdb;
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT
                partner_id,
                MAX(last_msg_id)    AS last_msg_id,
                MAX(last_time)      AS last_time,
                SUM(unread_cnt)     AS unread_cnt,
                partner_name, partner_avatar, partner_role
             FROM (
                SELECT
                    m.from_id AS partner_id,
                    MAX(m.id) AS last_msg_id,
                    MAX(m.created_at) AS last_time,
                    SUM(CASE WHEN m.is_read=0 AND m.to_id=%d THEN 1 ELSE 0 END) AS unread_cnt,
                    u.display_name AS partner_name,
                    u.avatar_url   AS partner_avatar,
                    u.role         AS partner_role
                FROM {$wpdb->prefix}forum_messages m
                JOIN {$wpdb->prefix}forum_users u ON u.id = m.from_id
                WHERE m.to_id=%d AND m.deleted_by_receiver=0
                GROUP BY m.from_id

                UNION ALL

                SELECT
                    m.to_id AS partner_id,
                    MAX(m.id) AS last_msg_id,
                    MAX(m.created_at) AS last_time,
                    0 AS unread_cnt,
                    u.display_name AS partner_name,
                    u.avatar_url   AS partner_avatar,
                    u.role         AS partner_role
                FROM {$wpdb->prefix}forum_messages m
                JOIN {$wpdb->prefix}forum_users u ON u.id = m.to_id
                WHERE m.from_id=%d AND m.deleted_by_sender=0
                GROUP BY m.to_id
             ) sub
             GROUP BY partner_id, partner_name, partner_avatar, partner_role
             ORDER BY last_time DESC",
            $user_id, $user_id, $user_id
        ) );
    }

    /** Nachrichten einer Konversation zwischen zwei Usern */
    public static function get_conversation( $user_id, $partner_id, $limit = 50, $offset = 0 ) {
        global $wpdb;
        // Neueste $limit Nachrichten ab $offset holen, dann aufsteigend sortieren
        return $wpdb->get_results( $wpdb->prepare(
            "SELECT * FROM (
                SELECT m.*, u.display_name AS sender_name, u.avatar_url AS sender_avatar
                FROM {$wpdb->prefix}forum_messages m
                JOIN {$wpdb->prefix}forum_users u ON u.id = m.from_id
                WHERE ( (m.from_id=%d AND m.to_id=%d AND m.deleted_by_sender=0)
                     OR (m.from_id=%d AND m.to_id=%d AND m.deleted_by_receiver=0) )
                ORDER BY m.created_at DESC
                LIMIT %d OFFSET %d
            ) sub ORDER BY sub.created_at ASC",
            $user_id, $partner_id, $partner_id, $user_id, $limit, $offset
        ) );
    }

    public static function count_conversation( $user_id, $partner_id ) {
        global $wpdb;
        return (int) $wpdb->get_var( $wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->prefix}forum_messages m
             WHERE ( (m.from_id=%d AND m.to_id=%d AND m.deleted_by_sender=0)
                  OR (m.from_id=%d AND m.to_id=%d AND m.deleted_by_receiver=0) )",
            $user_id, $partner_id, $partner_id, $user_id
        ) );
    }

    public static function mark_messages_read( $user_id, $partner_id ) {
        global $wpdb;
        $wpdb->query( $wpdb->prepare(
            "UPDATE {$wpdb->prefix}forum_messages SET is_read=1
             WHERE to_id=%d AND from_id=%d AND is_read=0",
            $user_id, $partner_id
        ) );
    }

    public static function count_unread_messages( $user_id ) {
        global $wpdb;
        $table = "{$wpdb->prefix}forum_messages";
        if ( $wpdb->get_var("SHOW TABLES LIKE '$table'") !== $table ) return 0;
        return (int)$wpdb->get_var( $wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->prefix}forum_messages WHERE to_id=%d AND is_read=0 AND deleted_by_receiver=0",
            $user_id
        ) );
    }

    // ── Remember-Me ───────────────────────────────────────────────────────────

    public static function create_remember_token( $user_id ) {
        global $wpdb;
        $token   = bin2hex( random_bytes(32) );
        $expires = date('Y-m-d H:i:s', strtotime('+30 days'));
        // Delete existing tokens for this user first
        $wpdb->delete( "{$wpdb->prefix}forum_remember_tokens", ['user_id' => $user_id] );
        $wpdb->insert( "{$wpdb->prefix}forum_remember_tokens", [
            'user_id'    => $user_id,
            'token'      => $token,
            'expires_at' => $expires,
        ] );
        return $token;
    }

    public static function verify_remember_token( $token ) {
        global $wpdb;
        $table = "{$wpdb->prefix}forum_remember_tokens";
        if ( $wpdb->get_var("SHOW TABLES LIKE '$table'") !== $table ) return null;
        return $wpdb->get_row( $wpdb->prepare(
            "SELECT user_id FROM {$wpdb->prefix}forum_remember_tokens
             WHERE token=%s AND expires_at > NOW()",
            sanitize_text_field($token)
        ) );
    }

    public static function delete_remember_token( $user_id ) {
        global $wpdb;
        $wpdb->delete( "{$wpdb->prefix}forum_remember_tokens", ['user_id' => (int)$user_id] );
    }

    // ── @Erwähnungen ──────────────────────────────────────────────────────────

    /** Extrahiert @usernames und gibt User-Objekte zurück */
    public static function extract_mentions( $content ) {
        preg_match_all( '/@([a-zA-Z0-9_]{3,60})/', $content, $m );
        $users = [];
        foreach ( array_unique($m[1]) as $username ) {
            $user = self::get_user_by('username', $username);
            if ($user) $users[] = $user;
        }
        return $users;
    }


    // ── Passwort-Reset ────────────────────────────────────────────────────────

    public static function create_reset_token( $user_id ) {
        global $wpdb;
        $token = bin2hex( random_bytes(32) );
        $hash  = hash( 'sha256', $token );
        // Alte Tokens löschen
        $wpdb->delete( "{$wpdb->prefix}forum_users", [] ); // nur placeholder
        $wpdb->query( $wpdb->prepare(
            "UPDATE {$wpdb->prefix}forum_users
              SET reset_token=%s, reset_token_expires=DATE_ADD(NOW(), INTERVAL 1 HOUR)
              WHERE id=%d",
            $hash, $user_id
        ) );
        return $token; // Klartext-Token → per E-Mail senden
    }

    public static function verify_reset_token( $token ) {
        global $wpdb;
        $hash = hash( 'sha256', $token );
        return $wpdb->get_row( $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}forum_users
              WHERE reset_token=%s AND reset_token_expires > NOW()",
            $hash
        ) );
    }

    public static function use_reset_token( $token, $new_password ) {
        global $wpdb;
        $user = self::verify_reset_token( $token );
        if ( ! $user ) return false;
        $wpdb->update(
            "{$wpdb->prefix}forum_users",
            [
                'password'             => password_hash( $new_password, PASSWORD_DEFAULT ),
                'reset_token'          => null,
                'reset_token_expires'  => null,
            ],
            ['id' => $user->id]
        );
        return true;
    }


}