protected function findAvailableHandlers(): Collection
    {
        return collect(config('laravel-slack-slash-command.handlers'))
            ->map(function (string $handlerClassName) {
                return new $handlerClassName($this->request);
            })
            ->filter(function (HandlesSlashCommand $handler) {
                return $handler instanceof SignatureHandler;
            })
            ->filter(function (SignatureHandler $handler) {
                $signatureParts = new SignatureParts($handler->getSignature());

                return Str::is($signatureParts->getSlashCommandName(), $this->request->command);
            });
    }