WP - Pretty urls for search results

nice-search-redirect.php

/**
 * Pretty urls for search results
 */
function nice_search_redirect() {
	global $wp_rewrite;

	if (!isset($wp_rewrite) || !is_object( $wp_rewrite ) || !$wp_rewrite->using_permalinks())
	return;

	$search_base = $wp_rewrite->search_base;
	if (is_search() && !is_admin() && strpos($_SERVER['REQUEST_URI'], "/{$search_base}/") === false) {
		wp_redirect( home_url("/{$search_base}/" . urlencode(get_query_var('s'))));
		exit();
	}
}
add_action('template_redirect', 'nice_search_redirect');