diff --git a/td/telegram/CountryInfoManager.cpp b/td/telegram/CountryInfoManager.cpp
index bbb500d58..a7842c556 100644
--- a/td/telegram/CountryInfoManager.cpp
+++ b/td/telegram/CountryInfoManager.cpp
@@ -451,7 +451,7 @@ const CountryInfoManager::CountryList *CountryInfoManager::get_country_list(cons
       it = countries_.find(language_code);
       CHECK(it != countries_.end())
       auto *country = it->second.get();
-      load_country_list(language_code, country->hash, Auto());
+      load_country_list(language_code, country->hash, {});
       return country;
     }
     return nullptr;
@@ -460,7 +460,7 @@ const CountryInfoManager::CountryList *CountryInfoManager::get_country_list(cons
   auto *country = it->second.get();
   CHECK(country != nullptr);
   if (country->next_reload_time < Time::now()) {
-    load_country_list(language_code, country->hash, Auto());
+    load_country_list(language_code, country->hash, {});
   }
 
   return country;
diff --git a/tdactor/td/actor/PromiseFuture.h b/tdactor/td/actor/PromiseFuture.h
index 29b21b42b..08b8ca485 100644
--- a/tdactor/td/actor/PromiseFuture.h
+++ b/tdactor/td/actor/PromiseFuture.h
@@ -20,7 +20,6 @@
 #include <utility>
 
 namespace td {
-
 template <class T = Unit>
 class PromiseInterface {
  public:
@@ -43,6 +42,15 @@ class PromiseInterface {
       set_error(result.move_as_error());
     }
   }
+  void operator()(T &&value) {
+    set_value(std::move(value));
+  }
+  void operator()(Status &&error) {
+    set_error(std::move(error));
+  }
+  void operator()(Result<T> &&result) {
+    set_result(std::move(result));
+  }
   virtual bool is_cancellable() const {
     return false;
   }
@@ -56,10 +64,182 @@ class PromiseInterface {
   }
 };
 
+namespace detail {
+
+template <typename T>
+struct GetArg : public GetArg<decltype(&T::operator())> {};
+
+template <class C, class R, class Arg>
+class GetArg<R (C::*)(Arg)> {
+ public:
+  using type = Arg;
+};
+template <class C, class R, class Arg>
+class GetArg<R (C::*)(Arg) const> {
+ public:
+  using type = Arg;
+};
+
+template <class T>
+using get_arg_t = std::decay_t<typename GetArg<T>::type>;
+
+template <class T>
+struct DropResult {
+  using type = T;
+};
+
+template <class T>
+struct DropResult<Result<T>> {
+  using type = T;
+};
+
+template <class T>
+using drop_result_t = typename DropResult<T>::type;
+
+struct Ignore {
+  void operator()(Status &&error) {
+    error.ignore();
+  }
+};
+template <class ValueT, class FunctionOkT, class FunctionFailT = Ignore>
+class LambdaPromise : public PromiseInterface<ValueT> {
+  enum class OnFail { None, Ok, Fail };
+
+ public:
+  void set_value(ValueT &&value) override {
+    CHECK(has_lambda_.get());
+    do_ok(ok_, std::move(value));
+    on_fail_ = OnFail::None;
+  }
+  void set_error(Status &&error) override {
+    CHECK(has_lambda_.get());
+    do_error(std::move(error));
+  }
+  LambdaPromise(const LambdaPromise &other) = delete;
+  LambdaPromise &operator=(const LambdaPromise &other) = delete;
+  LambdaPromise(LambdaPromise &&other) = default;
+  LambdaPromise &operator=(LambdaPromise &&other) = default;
+  ~LambdaPromise() override {
+    if (has_lambda_.get()) {
+      do_error(Status::Error("Lost promise"));
+    }
+  }
+
+  template <class FromOkT, class FromFailT>
+  LambdaPromise(FromOkT &&ok, FromFailT &&fail, bool use_ok_as_fail)
+      : ok_(std::forward<FromOkT>(ok))
+      , fail_(std::forward<FromFailT>(fail))
+      , on_fail_(use_ok_as_fail ? OnFail::Ok : OnFail::Fail), has_lambda_(true) {
+  }
+  template <class FromOkT>
+  LambdaPromise(FromOkT &&ok) : LambdaPromise(std::move(ok), Ignore(), true) {
+  }
+
+ private:
+  FunctionOkT ok_;
+  FunctionFailT fail_;
+  OnFail on_fail_ = OnFail::None;
+  MovableValue<bool> has_lambda_{false};
+
+  void do_error(Status &&error) {
+    switch (on_fail_) {
+      case OnFail::None:
+        break;
+      case OnFail::Ok:
+        do_error(ok_, std::move(error));
+        break;
+      case OnFail::Fail:
+        do_error(fail_, std::move(error));
+        break;
+    }
+    on_fail_ = OnFail::None;
+  }
+
+  template <class F>
+  std::enable_if_t<is_callable<F, Result<ValueT>>::value, void> do_error(F &&f, Status &&status) {
+    f(Result<ValueT>(std::move(status)));
+  }
+  template <class Y, class F>
+  std::enable_if_t<!is_callable<F, Result<ValueT>>::value, void> do_error(F &&f, Y &&status) {
+    f(Auto());
+  }
+  template <class F>
+  std::enable_if_t<is_callable<F, Result<ValueT>>::value, void> do_ok(F &&f, ValueT &&result) {
+    f(Result<ValueT>(std::move(result)));
+  }
+  template <class F >
+  std::enable_if_t<!is_callable<F, Result<ValueT>>::value, void> do_ok(F &&f, ValueT &&result) {
+    f(std::move(result));
+  }
+};
+}
+
 template <class T>
 class SafePromise;
 
 template <class T = Unit>
+class Promise;
+
+constexpr std::false_type is_promise_interface(...) {
+  return {};
+}
+template <class T>
+constexpr std::true_type is_promise_interface(const PromiseInterface<T> &promise) {
+  return {};
+}
+template <class T>
+constexpr std::true_type is_promise_interface(const Promise<T> &promise) {
+  return {};
+}
+
+template <class F>
+constexpr bool is_promise_interface() {
+  return decltype(is_promise_interface(std::declval<F>()))::value;
+}
+
+constexpr std::false_type is_promise_interface_ptr(...) {
+  return {};
+}
+template <class T>
+constexpr std::true_type is_promise_interface_ptr(const unique_ptr<T> &promise) {
+  return {};
+}
+
+template <class F>
+constexpr bool is_promise_interface_ptr() {
+  return decltype(is_promise_interface_ptr(std::declval<F>()))::value;
+}
+template <class T = void, class F = void, std::enable_if_t<std::is_same<T, void>::value, bool> has_t = false>
+auto lambda_promise(F &&f) {
+  return detail::LambdaPromise<detail::drop_result_t<detail::get_arg_t<std::decay_t<F>>>, std::decay_t<F>>(std::forward<F>(f));
+}
+template <class T = void, class F = void, std::enable_if_t<!std::is_same<T, void>::value, bool> has_t = true>
+auto lambda_promise(F &&f) {
+  return detail::LambdaPromise<T, std::decay_t<F>>(std::forward<F>(f));
+}
+
+template <class T, class F, std::enable_if_t<is_promise_interface<F>(), bool> from_promise_inerface = true>
+auto &&promise_interface(F &&f) {
+  return std::forward<F>(f);
+}
+
+template <class T, class F, std::enable_if_t<!is_promise_interface<F>(), bool> from_promise_inerface = false>
+auto promise_interface(F &&f) {
+  return lambda_promise<T>(std::forward<F>(f));
+}
+
+template <class T, class F, std::enable_if_t<is_promise_interface_ptr<F>(), bool> from_promise_inerface = true>
+auto promise_interface_ptr(F &&f) {
+  return std::forward<F>(f);
+}
+template <class T, class F, std::enable_if_t<!is_promise_interface_ptr<F>(), bool> from_promise_inerface = false>
+auto promise_interface_ptr(F &&f) {
+  return td::make_unique<std::decay_t<decltype(promise_interface<T>(std::forward<F>(f)))>>(
+      promise_interface<T>(std::forward<F>(f)));
+}
+
+
+template <class T>
 class Promise {
  public:
   void set_value(T &&value) {
@@ -83,6 +263,14 @@ class Promise {
     promise_->set_result(std::move(result));
     promise_.reset();
   }
+  template <class S>
+  void operator()(S &&result) {
+    if (!promise_) {
+      return;
+    }
+    promise_->operator()(std::forward<S>(result));
+    promise_.reset();
+  }
   void reset() {
     promise_.reset();
   }
@@ -117,8 +305,13 @@ class Promise {
   Promise() = default;
   explicit Promise(unique_ptr<PromiseInterface<T>> promise) : promise_(std::move(promise)) {
   }
+  Promise(Auto) {
+  }
   Promise(SafePromise<T> &&other);
   Promise &operator=(SafePromise<T> &&other);
+  template <class F>
+  Promise(F &&f) : promise_(promise_interface_ptr<T>(std::forward<F>(f))) {
+  }
 
   explicit operator bool() {
     return static_cast<bool>(promise_);
@@ -209,36 +402,6 @@ class EventPromise : public PromiseInterface<Unit> {
   }
 };
 
-template <typename T>
-struct GetArg : public GetArg<decltype(&T::operator())> {};
-
-template <class C, class R, class Arg>
-class GetArg<R (C::*)(Arg)> {
- public:
-  using type = Arg;
-};
-template <class C, class R, class Arg>
-class GetArg<R (C::*)(Arg) const> {
- public:
-  using type = Arg;
-};
-
-template <class T>
-using get_arg_t = std::decay_t<typename GetArg<T>::type>;
-
-template <class T>
-struct DropResult {
-  using type = T;
-};
-
-template <class T>
-struct DropResult<Result<T>> {
-  using type = T;
-};
-
-template <class T>
-using drop_result_t = typename DropResult<T>::type;
-
 template <class PromiseT>
 class CancellablePromise : public PromiseT {
  public:
@@ -257,62 +420,6 @@ class CancellablePromise : public PromiseT {
   CancellationToken cancellation_token_;
 };
 
-template <class ValueT, class FunctionOkT, class FunctionFailT>
-class LambdaPromise : public PromiseInterface<ValueT> {
-  enum class OnFail { None, Ok, Fail };
-
- public:
-  void set_value(ValueT &&value) override {
-    ok_(std::move(value));
-    on_fail_ = OnFail::None;
-  }
-  void set_error(Status &&error) override {
-    do_error(std::move(error));
-  }
-  LambdaPromise(const LambdaPromise &other) = delete;
-  LambdaPromise &operator=(const LambdaPromise &other) = delete;
-  LambdaPromise(LambdaPromise &&other) = delete;
-  LambdaPromise &operator=(LambdaPromise &&other) = delete;
-  ~LambdaPromise() override {
-    do_error(Status::Error("Lost promise"));
-  }
-
-  template <class FromOkT, class FromFailT>
-  LambdaPromise(FromOkT &&ok, FromFailT &&fail, bool use_ok_as_fail)
-      : ok_(std::forward<FromOkT>(ok))
-      , fail_(std::forward<FromFailT>(fail))
-      , on_fail_(use_ok_as_fail ? OnFail::Ok : OnFail::Fail) {
-  }
-
- private:
-  FunctionOkT ok_;
-  FunctionFailT fail_;
-  OnFail on_fail_ = OnFail::None;
-
-  template <class FuncT, class ArgT = detail::get_arg_t<FuncT>>
-  std::enable_if_t<std::is_assignable<ArgT, Status>::value> do_error_impl(FuncT &func, Status &&status) {
-    func(std::move(status));
-  }
-
-  template <class FuncT, class ArgT = detail::get_arg_t<FuncT>>
-  std::enable_if_t<!std::is_assignable<ArgT, Status>::value> do_error_impl(FuncT &func, Status &&status) {
-    func(Auto());
-  }
-
-  void do_error(Status &&error) {
-    switch (on_fail_) {
-      case OnFail::None:
-        break;
-      case OnFail::Ok:
-        do_error_impl(ok_, std::move(error));
-        break;
-      case OnFail::Fail:
-        fail_(std::move(error));
-        break;
-    }
-    on_fail_ = OnFail::None;
-  }
-};
 
 template <class... ArgsT>
 class JoinPromise : public PromiseInterface<Unit> {
@@ -331,6 +438,30 @@ class JoinPromise : public PromiseInterface<Unit> {
 };
 }  // namespace detail
 
+class SendClosure {
+ public:
+  template <class... ArgsT>
+  void operator()(ArgsT &&... args) const {
+    send_closure(std::forward<ArgsT>(args)...);
+  }
+};
+
+//template <class T>
+//template <class... ArgsT>
+//auto Promise<T>::send_closure(ArgsT &&... args) {
+//  return [promise = std::move(*this), t = std::make_tuple(std::forward<ArgsT>(args)...)](auto &&r_res) mutable {
+//    TRY_RESULT_PROMISE(promise, res, std::move(r_res));
+//    td2::call_tuple(SendClosure(), std::tuple_cat(std::move(t), std::make_tuple(std::move(res), std::move(promise))));
+//  };
+//}
+
+template <class... ArgsT>
+auto promise_send_closure(ArgsT &&... args) {
+  return [t = std::make_tuple(std::forward<ArgsT>(args)...)](auto &&res) mutable {
+    call_tuple(SendClosure(), std::tuple_cat(std::move(t), std::make_tuple(std::move(res))));
+  };
+}
+
 /*** FutureActor and PromiseActor ***/
 template <class T>
 class FutureActor;
@@ -559,16 +690,12 @@ FutureActor<T> send_promise(ActorId<ActorAT> actor_id, ResultT (ActorBT::*func)(
 
 class PromiseCreator {
  public:
-  struct Ignore {
-    void operator()(Status &&error) {
-      error.ignore();
-    }
-  };
+  using Ignore = detail::Ignore;
 
   template <class OkT, class ArgT = detail::drop_result_t<detail::get_arg_t<OkT>>>
   static Promise<ArgT> lambda(OkT &&ok) {
     return Promise<ArgT>(
-        td::make_unique<detail::LambdaPromise<ArgT, std::decay_t<OkT>, Ignore>>(std::forward<OkT>(ok), Ignore(), true));
+        td::make_unique<detail::LambdaPromise<ArgT, std::decay_t<OkT>>>(std::forward<OkT>(ok)));
   }
 
   template <class OkT, class FailT, class ArgT = detail::get_arg_t<OkT>>
@@ -580,8 +707,8 @@ class PromiseCreator {
   template <class OkT, class ArgT = detail::drop_result_t<detail::get_arg_t<OkT>>>
   static auto cancellable_lambda(CancellationToken cancellation_token, OkT &&ok) {
     return Promise<ArgT>(
-        td::make_unique<detail::CancellablePromise<detail::LambdaPromise<ArgT, std::decay_t<OkT>, Ignore>>>(
-            std::move(cancellation_token), std::forward<OkT>(ok), Ignore(), true));
+        td::make_unique<detail::CancellablePromise<detail::LambdaPromise<ArgT, std::decay_t<OkT>>>>(
+            std::move(cancellation_token), std::forward<OkT>(ok)));
   }
 
   static Promise<> event(EventFull &&ok) {
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 6fab03211..33b3fa426 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -33,16 +33,19 @@ set(TESTS_MAIN
 if (NOT CMAKE_CROSSCOMPILING OR EMSCRIPTEN)
   #Tests
   add_executable(test-tdutils EXCLUDE_FROM_ALL ${TESTS_MAIN} ${TDUTILS_TEST_SOURCE})
+  add_executable(test-online EXCLUDE_FROM_ALL online.cpp)
   add_executable(run_all_tests ${TESTS_MAIN} ${TD_TEST_SOURCE})
   if (CLANG AND NOT CYGWIN AND NOT EMSCRIPTEN AND NOT (CMAKE_HOST_SYSTEM_NAME MATCHES "OpenBSD"))
     target_compile_options(test-tdutils PUBLIC -fsanitize=undefined -fno-sanitize=vptr)
     target_compile_options(run_all_tests PUBLIC -fsanitize=undefined -fno-sanitize=vptr)
+    target_compile_options(test-online PUBLIC -fsanitize=undefined -fno-sanitize=vptr)
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fsanitize=undefined -fno-sanitize=vptr")
   endif()
   target_include_directories(run_all_tests PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>)
   target_include_directories(test-tdutils PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>)
   target_link_libraries(test-tdutils PRIVATE tdutils)
   target_link_libraries(run_all_tests PRIVATE tdcore tdclient)
+  target_link_libraries(test-online PRIVATE tdcore tdclient tdutils tdactor)
 
   if (CLANG)
 #    add_executable(fuzz_url fuzz_url.cpp)
diff --git a/test/online.cpp b/test/online.cpp
new file mode 100644
index 000000000..308673e23
--- /dev/null
+++ b/test/online.cpp
@@ -0,0 +1,622 @@
+
+#include <iostream>
+#include <tdutils/td/utils/FileLog.h>
+#include <tdutils/td/utils/OptionParser.h>
+#include <tdutils/td/utils/port/path.h>
+#include <td/telegram/ClientActor.h>
+#include <tdutils/td/utils/filesystem.h>
+#include "td/telegram/TdCallback.h"
+#include "td/utils/port/signals.h"
+#include "td/telegram/Log.h"
+#include "td/utils/crypto.h"
+#include "td/utils/misc.h"
+#include "td/utils/Random.h"
+#include "td/actor/actor.h"
+#include "td/actor/PromiseFuture.h"
+#include "td/actor/MultiPromise.h"
+#include "td/telegram/td_api_json.h"
+
+namespace td {
+template <class T>
+static void check_td_error(T &result) {
+  LOG_CHECK(result->get_id() != td::td_api::error::ID) << to_string(result);
+}
+
+class TestClient : public Actor {
+ public:
+  explicit TestClient(td::string name) : name_(std::move(name)) {
+  }
+  struct Update {
+    td::uint64 id;
+    td::tl_object_ptr<td::td_api::Object> object;
+    Update(td::uint64 id, td::tl_object_ptr<td::td_api::Object> object) : id(id), object(std::move(object)) {
+    }
+  };
+  class Listener {
+   public:
+    Listener() = default;
+    Listener(const Listener &) = delete;
+    Listener &operator=(const Listener &) = delete;
+    Listener(Listener &&) = delete;
+    Listener &operator=(Listener &&) = delete;
+    virtual ~Listener() = default;
+    virtual void start_listen(TestClient *client) {
+    }
+    virtual void stop_listen() {
+    }
+    virtual void on_update(std::shared_ptr<Update> update) = 0;
+  };
+  struct RemoveListener {
+    void operator()(Listener *listener) {
+      send_closure(self, &TestClient::remove_listener, listener);
+    }
+    ActorId<TestClient> self;
+  };
+  using ListenerToken = std::unique_ptr<Listener, RemoveListener>;
+  void close(td::Promise<> close_promise) {
+    close_promise_ = std::move(close_promise);
+    td_client_.reset();
+  }
+
+  td::unique_ptr<td::TdCallback> make_td_callback() {
+    class TdCallbackImpl : public td::TdCallback {
+     public:
+      explicit TdCallbackImpl(td::ActorId<TestClient> client) : client_(client) {
+      }
+      void on_result(td::uint64 id, td::tl_object_ptr<td::td_api::Object> result) override {
+        send_closure(client_, &TestClient::on_result, id, std::move(result));
+      }
+      void on_error(td::uint64 id, td::tl_object_ptr<td::td_api::error> error) override {
+        send_closure(client_, &TestClient::on_error, id, std::move(error));
+      }
+      TdCallbackImpl(const TdCallbackImpl &) = delete;
+      TdCallbackImpl &operator=(const TdCallbackImpl &) = delete;
+      TdCallbackImpl(TdCallbackImpl &&) = delete;
+      TdCallbackImpl &operator=(TdCallbackImpl &&) = delete;
+      ~TdCallbackImpl() override {
+        send_closure(client_, &TestClient::on_closed);
+      }
+
+     private:
+      td::ActorId<TestClient> client_;
+    };
+    return td::make_unique<TdCallbackImpl>(actor_id(this));
+  }
+
+  void add_listener(td::unique_ptr<Listener> listener) {
+    auto *ptr = listener.get();
+    listeners_.push_back(std::move(listener));
+    ptr->start_listen(this);
+  }
+  void remove_listener(Listener *listener) {
+    pending_remove_.push_back(listener);
+  }
+  void do_pending_remove_listeners() {
+    for (auto listener : pending_remove_) {
+      do_remove_listener(listener);
+    }
+    pending_remove_.clear();
+  }
+  void do_remove_listener(Listener *listener) {
+    for (size_t i = 0; i < listeners_.size(); i++) {
+      if (listeners_[i].get() == listener) {
+        listener->stop_listen();
+        listeners_.erase(listeners_.begin() + i);
+        break;
+      }
+    }
+  }
+
+  void on_result(td::uint64 id, td::tl_object_ptr<td::td_api::Object> result) {
+    on_update(std::make_shared<Update>(id, std::move(result)));
+  }
+  void on_error(td::uint64 id, td::tl_object_ptr<td::td_api::error> error) {
+    on_update(std::make_shared<Update>(id, std::move(error)));
+  }
+  void on_update(std::shared_ptr<Update> update) {
+    for (auto &listener : listeners_) {
+      listener->on_update(update);
+    }
+    do_pending_remove_listeners();
+  }
+
+  void on_closed() {
+    stop();
+  }
+
+  void start_up() override {
+    auto old_context = set_context(std::make_shared<td::ActorContext>());
+    set_tag(name_);
+    LOG(INFO) << "START UP!";
+
+    td_client_ = td::create_actor<td::ClientActor>("Td-proxy", make_td_callback());
+  }
+
+  td::ActorOwn<td::ClientActor> td_client_;
+
+  td::string name_;
+
+ private:
+  td::vector<td::unique_ptr<Listener>> listeners_;
+  td::vector<Listener *> pending_remove_;
+
+  td::Promise<> close_promise_;
+};
+
+class Task : public TestClient::Listener {
+ public:
+  void on_update(std::shared_ptr<TestClient::Update> update) override {
+    auto it = sent_queries_.find(update->id);
+    if (it != sent_queries_.end()) {
+      it->second(std::move(update->object));
+      sent_queries_.erase(it);
+    }
+    process_update(update);
+  }
+  void start_listen(TestClient *client) override {
+    client_ = client;
+    start_up();
+  }
+  virtual void process_update(std::shared_ptr<TestClient::Update> update) {
+  }
+
+  template <class FunctionT, class CallbackT>
+  void send_query(td::tl_object_ptr<FunctionT> function, CallbackT callback) {
+    auto id = current_query_id_++;
+
+    using ResultT = typename FunctionT::ReturnType;
+    sent_queries_[id] =
+        [callback = Promise<ResultT>(std::move(callback))](Result<tl_object_ptr<td_api::Object>> r_obj) mutable {
+          TRY_RESULT_PROMISE(callback, obj, std::move(r_obj));
+          if (obj->get_id() == td::td_api::error::ID) {
+            auto err = move_tl_object_as<td_api::error>(std::move(obj));
+            callback.set_error(Status::Error(err->code_, err->message_));
+            return;
+          }
+          callback.set_value(move_tl_object_as<typename ResultT::element_type>(std::move(obj)));
+        };
+    send_closure(client_->td_client_, &td::ClientActor::request, id, std::move(function));
+  }
+
+ protected:
+  std::map<td::uint64, Promise<td::tl_object_ptr<td::td_api::Object>>> sent_queries_;
+  TestClient *client_ = nullptr;
+  td::uint64 current_query_id_ = 1;
+
+  virtual void start_up() {
+  }
+  void stop() {
+    client_->remove_listener(this);
+    client_ = nullptr;
+  }
+  bool is_alive() const {
+    return client_ != nullptr;
+  }
+};
+
+class InitTask : public Task {
+ public:
+  struct Options {
+    string name;
+    int32 api_id;
+    string api_hash;
+  };
+  InitTask(Options options, td::Promise<> promise) : options_(std::move(options)), promise_(std::move(promise)) {
+  }
+
+ private:
+  Options options_;
+  td::Promise<> promise_;
+  bool start_flag_{false};
+
+  void start_up() override {
+    send_query(td::make_tl_object<td::td_api::getAuthorizationState>(),
+               [this](auto res) { this->process_authorization_state(res.move_as_ok()); });
+  }
+  void process_authorization_state(td::tl_object_ptr<td::td_api::Object> authorization_state) {
+    start_flag_ = true;
+    td::tl_object_ptr<td::td_api::Function> function;
+    switch (authorization_state->get_id()) {
+      case td::td_api::authorizationStateWaitEncryptionKey::ID:
+        send(td::make_tl_object<td::td_api::checkDatabaseEncryptionKey>());
+        break;
+      case td::td_api::authorizationStateReady::ID:
+        promise_.set_value({});
+        stop();
+        break;
+      case td::td_api::authorizationStateWaitTdlibParameters::ID: {
+        auto parameters = td::td_api::make_object<td::td_api::tdlibParameters>();
+        parameters->use_test_dc_ = true;
+        parameters->database_directory_ = options_.name + TD_DIR_SLASH;
+        parameters->use_message_database_ = true;
+        parameters->use_secret_chats_ = true;
+        parameters->api_id_ = options_.api_id;
+        parameters->api_hash_ = options_.api_hash;
+        parameters->system_language_code_ = "en";
+        parameters->device_model_ = "Desktop";
+        parameters->application_version_ = "tdclient-test";
+        parameters->ignore_file_names_ = false;
+        parameters->enable_storage_optimizer_ = true;
+        send(td::td_api::make_object<td::td_api::setTdlibParameters>(std::move(parameters)));
+        break;
+      }
+      default:
+        LOG(ERROR) << "???";
+        promise_.set_error(
+            Status::Error(PSLICE() << "Unexpected authorization state " << to_string(authorization_state)));
+        stop();
+        break;
+    }
+  }
+  template <class T>
+  void send(T &&query) {
+    send_query(std::move(query), [this](auto res) {
+      if (is_alive()) {
+        res.ensure();
+      }
+    });
+  }
+  void process_update(std::shared_ptr<TestClient::Update> update) override {
+    if (!start_flag_) {
+      return;
+    }
+    if (!update->object) {
+      return;
+    }
+    if (update->object->get_id() == td::td_api::updateAuthorizationState::ID) {
+      auto update_authorization_state = td::move_tl_object_as<td::td_api::updateAuthorizationState>(update->object);
+      process_authorization_state(std::move(update_authorization_state->authorization_state_));
+    }
+  }
+};
+
+class GetMe : public Task {
+ public:
+  struct Result {
+    int32 user_id;
+    int64 chat_id;
+  };
+  GetMe(Promise<Result> promise) : promise_(std::move(promise)) {
+  }
+  void start_up() override {
+    send_query(td::make_tl_object<td::td_api::getMe>(), [this](auto res) { with_user_id(res.move_as_ok()->id_); });
+  }
+
+ private:
+  Promise<Result> promise_;
+  Result result_;
+
+  void with_user_id(int32 user_id) {
+    result_.user_id = user_id;
+    send_query(td::make_tl_object<td::td_api::createPrivateChat>(user_id, false), [this](auto res) { with_chat_id(res.move_as_ok()->id_); });
+  }
+
+  void with_chat_id(int64 chat_id) {
+    result_.chat_id = chat_id;
+    promise_.set_value(std::move(result_));
+    stop();
+  }
+};
+
+class UploadFile : public Task {
+ public:
+  struct Result {
+    std::string content;
+    std::string remote_id;
+  };
+  UploadFile(std::string dir, std::string content, int64 chat_id, Promise<Result> promise) : dir_(std::move(dir)), content_(std::move(content)), chat_id_(std::move(chat_id)), promise_(std::move(promise)) {
+  }
+  void start_up() override {
+    auto hash = hex_encode(sha256(content_)).substr(0, 10);
+    content_path_ = dir_ + TD_DIR_SLASH + hash + ".data";
+    id_path_ = dir_ + TD_DIR_SLASH + hash + ".id";
+
+    auto r_id = read_file(id_path_);
+    if (r_id.is_ok() && r_id.ok().size() > 10) {
+      auto id = r_id.move_as_ok();
+      LOG(ERROR) << "Got file from cache";
+      Result res;
+      res.content = std::move(content_);
+      res.remote_id = id.as_slice().str();
+      promise_.set_value(std::move(res));
+      stop();
+      return;
+    }
+
+    write_file(content_path_, content_).ensure();
+
+    send_query(td::make_tl_object<td::td_api::sendMessage>(
+        chat_id_, 0, 0, nullptr, nullptr,
+        td::make_tl_object<td::td_api::inputMessageDocument>(
+            td::make_tl_object<td::td_api::inputFileLocal>(content_path_), nullptr, true,
+            td::make_tl_object<td::td_api::formattedText>("tag", td::Auto()))),
+               [this](auto res) { with_message(res.move_as_ok()); });
+  }
+
+ private:
+  std::string dir_;
+  std::string content_path_;
+  std::string id_path_;
+  std::string content_;
+  int64 chat_id_;
+  Promise<Result> promise_;
+  int64 file_id_{0};
+
+  void with_message(td::tl_object_ptr<td_api::message> message) {
+    CHECK(message->content_->get_id() == td::td_api::messageDocument::ID);
+    auto messageDocument = td::move_tl_object_as<td::td_api::messageDocument>(message->content_);
+    on_file(*messageDocument->document_->document_, true);
+  }
+
+  void on_file(const td_api::file &file, bool force = false) {
+    if (force) {
+      file_id_ = file.id_;
+    }
+    if (file.id_ != file_id_) {
+      return;
+    }
+    if (file.remote_->is_uploading_completed_) {
+      Result res;
+      res.content = std::move(content_);
+      res.remote_id = file.remote_->id_;
+
+      unlink(content_path_).ignore();
+      atomic_write_file(id_path_, res.remote_id).ignore();
+
+      promise_.set_value(std::move(res));
+      stop();
+    }
+  }
+
+  void process_update(std::shared_ptr<TestClient::Update> update) override {
+    if (!update->object) {
+      return;
+    }
+    if (update->object->get_id() == td::td_api::updateFile::ID) {
+      auto updateFile = td::move_tl_object_as<td::td_api::updateFile>(update->object);
+      on_file(*updateFile->file_);
+    }
+  }
+};
+
+class TestDownloadFile : public Task {
+ public:
+  TestDownloadFile(std::string remote_id, std::string content, Promise<Unit> promise) : remote_id_(std::move(remote_id)), content_(std::move(content)), promise_(std::move(promise)) {
+  }
+  void start_up() override {
+    send_query(td::make_tl_object<td::td_api::getRemoteFile>(
+        remote_id_, nullptr
+    ), [this](auto res) { start_file(*res.ok()); });
+  }
+
+ private:
+  std::string remote_id_;
+  std::string content_;
+  Promise<Unit> promise_;
+  struct Range {
+    size_t begin;
+    size_t end;
+  };
+  int32 file_id_{0};
+  std::vector<Range> ranges_;
+
+
+  void start_file(const td_api::file &file) {
+    LOG(ERROR) << "Start";
+    file_id_ = file.id_;
+//    CHECK(!file.local_->is_downloading_active_);
+//    CHECK(!file.local_->is_downloading_completed_);
+//    CHECK(file.local_->download_offset_ == 0);
+    if (!file.local_->path_.empty()) {
+      unlink(file.local_->path_).ignore();
+    }
+
+    size_t size = file.size_;
+    Random::Xorshift128plus rnd(123);
+
+    size_t begin = 0;
+
+    while (begin + 128u < size) {
+      auto chunk_size = rnd.fast(128, 3096);
+      auto end = begin + chunk_size;
+      if (end > size) {
+        end = size;
+      }
+
+      ranges_.push_back({begin, end});
+      begin = end;
+    }
+
+    random_shuffle(as_mutable_span(ranges_), rnd);
+    start_chunk();
+  }
+
+  void got_chunk(const td_api::file &file) {
+    LOG(ERROR) << "Got chunk";
+    auto range = ranges_.back();
+    std::string got_chunk(range.end - range.begin, '\0');
+    FileFd::open(file.local_->path_, FileFd::Flags::Read).move_as_ok().pread(got_chunk, range.begin).ensure();
+    CHECK(got_chunk == as_slice(content_).substr(range.begin, range.end - range.begin));
+    ranges_.pop_back();
+    if (ranges_.empty()) {
+      promise_.set_value(Unit{});
+      return stop();
+    }
+    start_chunk();
+  }
+
+  void start_chunk() {
+
+    send_query(td::make_tl_object<td::td_api::downloadFile>(
+        file_id_, 1, int(ranges_.back().begin), int(ranges_.back().end - ranges_.back().begin), true
+    ), [this](auto res) { got_chunk(*res.ok()); });
+
+  }
+};
+
+std::string gen_readable_file(size_t block_size, size_t block_count) {
+  std::string content;
+  for (size_t block_id = 0; block_id < block_count; block_id++) {
+    std::string block;
+    for (size_t line = 0; block.size() < block_size; line++) {
+      block += PSTRING() << "\nblock=" << block_id << ", line=" << line;
+    }
+    block.resize(block_size);
+    content += block;
+  }
+  return content;
+}
+
+class TestTd : public Actor {
+ public:
+  struct Options {
+    std::string alice_dir = "alice";
+    std::string bob_dir = "bob";
+    int32 api_id{0};
+    string api_hash;
+  };
+
+  TestTd(Options options) : options_(std::move(options)) {
+  }
+
+ private:
+  Options options_;
+  ActorOwn<TestClient> alice_;
+  GetMe::Result alice_id_;
+  std::string alice_cache_dir_;
+  ActorOwn<TestClient> bob_;
+
+  void start_up() override {
+    alice_ = create_actor<TestClient>("Alice", "Alice");
+    bob_ = create_actor<TestClient>("Bob", "Bob");
+
+    MultiPromiseActorSafe mp("init");
+    mp.add_promise(promise_send_closure(actor_id(this), &TestTd::check_init));
+
+    InitTask::Options options;
+    options.api_id = options_.api_id;
+    options.api_hash = options_.api_hash;
+
+    options.name = options_.alice_dir;
+    td::send_closure(alice_, &TestClient::add_listener, td::make_unique<InitTask>(options, mp.get_promise()));
+    options.name = options_.bob_dir;
+    td::send_closure(bob_, &TestClient::add_listener, td::make_unique<InitTask>(options, mp.get_promise()));
+  }
+
+  void check_init(Result<Unit> res) {
+    LOG_IF(FATAL, res.is_error()) << res.error();
+    alice_cache_dir_ = options_.alice_dir + TD_DIR_SLASH + "cache";
+    mkdir(alice_cache_dir_).ignore();
+
+    td::send_closure(alice_, &TestClient::add_listener,
+                     td::make_unique<GetMe>(promise_send_closure(actor_id(this), &TestTd::with_alice_id)));
+
+    //close();
+  }
+
+  void with_alice_id(Result<GetMe::Result> alice_id) {
+    alice_id_ = alice_id.move_as_ok();
+    LOG(ERROR) << "Alice user_id=" << alice_id_.user_id << ", chat_id=" << alice_id_.chat_id;
+    auto content = gen_readable_file(65536, 20);
+    send_closure(alice_, &TestClient::add_listener,
+                     td::make_unique<UploadFile>(alice_cache_dir_,  std::move(content), alice_id_.chat_id, promise_send_closure(actor_id(this), &TestTd::with_file)));
+  }
+  void with_file(Result<UploadFile::Result> r_result) {
+    auto result = r_result.move_as_ok();
+    send_closure(alice_, &TestClient::add_listener,
+                 td::make_unique<TestDownloadFile>(result.remote_id, std::move(result.content), promise_send_closure(actor_id(this), &TestTd::after_test_download_file)));
+  }
+  void after_test_download_file(Result<Unit>) {
+    close();
+  }
+
+
+  void close() {
+    MultiPromiseActorSafe mp("close");
+    mp.add_promise(promise_send_closure(actor_id(this), &TestTd::check_close));
+    td::send_closure(alice_, &TestClient::close, mp.get_promise());
+    td::send_closure(bob_, &TestClient::close, mp.get_promise());
+  }
+
+  void check_close(Result<Unit> res) {
+    Scheduler::instance()->finish();
+    stop();
+  }
+};
+
+static void fail_signal(int sig) {
+  signal_safe_write_signal_number(sig);
+  while (true) {
+    // spin forever to allow debugger to attach
+  }
+}
+
+static void on_fatal_error(const char *error) {
+  std::cerr << "Fatal error: " << error << std::endl;
+}
+int main(int argc, char **argv) {
+  ignore_signal(SignalType::HangUp).ensure();
+  ignore_signal(SignalType::Pipe).ensure();
+  set_signal_handler(SignalType::Error, fail_signal).ensure();
+  set_signal_handler(SignalType::Abort, fail_signal).ensure();
+  Log::set_fatal_error_callback(on_fatal_error);
+  init_openssl_threads();
+
+  TestTd::Options test_options;
+
+  test_options.api_id = [](auto x) -> int32 {
+    if (x) {
+      return to_integer<int32>(Slice(x));
+    }
+    return 0;
+  }(std::getenv("TD_API_ID"));
+  test_options.api_hash = [](auto x) -> std::string {
+    if (x) {
+      return x;
+    }
+    return std::string();
+  }(std::getenv("TD_API_HASH"));
+
+  int new_verbosity_level = VERBOSITY_NAME(INFO);
+
+  OptionParser options;
+  options.set_description("TDLib experimental tester");
+  options.add_option('v', "verbosity", "Set verbosity level", [&](Slice level) {
+    int new_verbosity = 1;
+    while (begins_with(level, "v")) {
+      new_verbosity++;
+      level.remove_prefix(1);
+    }
+    if (!level.empty()) {
+      new_verbosity += to_integer<int>(level) - (new_verbosity == 1);
+    }
+    new_verbosity_level = VERBOSITY_NAME(FATAL) + new_verbosity;
+  });
+  options.add_check([&] {
+    if (test_options.api_id == 0 || test_options.api_hash.empty()) {
+      return Status::Error("You must provide valid api-id and api-hash obtained at https://my.telegram.org");
+    }
+    return Status::OK();
+  });
+  auto r_non_options = options.run(argc, argv, 0);
+  if (r_non_options.is_error()) {
+    LOG(PLAIN) << argv[0] << ": " << r_non_options.error().message();
+    LOG(PLAIN) << options;
+    return 1;
+  }
+  SET_VERBOSITY_LEVEL(new_verbosity_level);
+
+  td::ConcurrentScheduler sched;
+  sched.init(4);
+  sched.create_actor_unsafe<TestTd>(0, "TestTd", std::move(test_options)).release();
+  sched.start();
+  while (sched.run_main(10)) {
+  }
+  sched.finish();
+  return 0;
+}
+}  // namespace td
+
+int main(int argc, char **argv) {
+  return td::main(argc, argv);
+}