if ( !Http::$httpEngine ) {
Http::$httpEngine = function_exists( 'curl_init' ) ? 'curl' : 'php';
} elseif ( Http::$httpEngine == 'curl' && !function_exists( 'curl_init' ) ) {
if ( !Http::$httpEngine ) {
Http::$httpEngine = function_exists( 'curl_init' ) ? 'curl' : 'php';
} elseif ( Http::$httpEngine == 'curl' && !function_exists( 'curl_init' ) ) {