// TEMP: Keyphrase bulk importer via REST
add_action('rest_api_init', function() {
    register_rest_route('lsc/v1', '/bulk-kw', array(
        'methods' => 'POST',
        'callback' => 'lsc_process_kw_csv',
        'permission_callback' => function() { return current_user_can('manage_options'); }
    ));
});
function lsc_process_kw_csv($request) {
    $csv = $request->get_param('csv');
    $rows = explode("\n", $csv);
    $updated = 0; $errors = array();
    foreach ($rows as $i => $row) {
        if ($i === 0 || empty(trim($row))) continue;
        $cols = str_getcsv($row);
        $post_id = intval($cols[0] ?? 0);
        $kw = sanitize_text_field($cols[1] ?? '');
        if ($post_id > 0 && !empty($kw)) {
            update_post_meta($post_id, '_yoast_wpseo_focuskw', $kw);
            $updated++;
        } else { $errors[] = "row $i: id=$post_id kw=$kw"; }
    }
    return new WP_REST_Response(array('updated'=>$updated,'errors'=>count($errors),'sample_errors'=>array_slice($errors,0,5)), 200);
}
// END TEMP