From 5624f9115555efc0e18997a52ea7d4f0f7ce686f Mon Sep 17 00:00:00 2001
From: levlam <levlam@telegram.org>
Date: Fri, 19 Jan 2024 15:35:57 +0300
Subject: [PATCH] Add td_api::canSendMessageToUser.

---
 td/generate/scheme/td_api.tl    |  4 ++++
 td/telegram/ContactsManager.cpp | 21 +++++++++++++++++++++
 td/telegram/ContactsManager.h   |  2 ++
 td/telegram/Td.cpp              |  6 ++++++
 td/telegram/Td.h                |  2 ++
 td/telegram/cli.cpp             |  4 ++++
 6 files changed, 39 insertions(+)

diff --git a/td/generate/scheme/td_api.tl b/td/generate/scheme/td_api.tl
index 3ac0c8b58..cdb80c1ca 100644
--- a/td/generate/scheme/td_api.tl
+++ b/td/generate/scheme/td_api.tl
@@ -9525,6 +9525,10 @@ setNewChatPrivacySettings settings:newChatPrivacySettings = Ok;
 getNewChatPrivacySettings = NewChatPrivacySettings;
 
 
+//@description Check whether the current user can message another user or try to create a chat with them @user_id Identifier of the other user
+canSendMessageToUser user_id:int53 = Ok;
+
+
 //@description Returns the value of an option by its name. (Check the list of available options on https://core.telegram.org/tdlib/options.) Can be called before authorization. Can be called synchronously for options "version" and "commit_hash"
 //@name The name of the option
 getOption name:string = OptionValue;
diff --git a/td/telegram/ContactsManager.cpp b/td/telegram/ContactsManager.cpp
index ce3e3a5ac..90b8c63da 100644
--- a/td/telegram/ContactsManager.cpp
+++ b/td/telegram/ContactsManager.cpp
@@ -5491,6 +5491,27 @@ int32 ContactsManager::get_user_was_online(const User *u, UserId user_id, int32
   return was_online;
 }
 
+void ContactsManager::can_send_message_to_user(UserId user_id, Promise<Unit> &&promise) {
+  if (user_id == get_my_id()) {
+    return promise.set_value(Unit());
+  }
+  const auto *u = get_user(user_id);
+  if (!have_input_peer_user(u, user_id, AccessRights::Write)) {
+    return promise.set_error(Status::Error(400, "Have no write access to the chat"));
+  }
+  if (!u->contact_require_premium || td_->option_manager_->get_option_boolean("is_premium") || u->is_mutual_contact) {
+    return promise.set_value(Unit());
+  }
+  auto user_full = get_user_full_force(user_id, "can_send_message_to_user");
+  if (user_full != nullptr) {
+    if (!user_full->contact_require_premium) {
+      return promise.set_value(Unit());
+    }
+    return promise.set_error(Status::Error(400, "Can't write to the user first"));
+  }
+  return promise.set_value(Unit());
+}
+
 void ContactsManager::load_contacts(Promise<Unit> &&promise) {
   if (td_->auth_manager_->is_bot()) {
     are_contacts_loaded_ = true;
diff --git a/td/telegram/ContactsManager.h b/td/telegram/ContactsManager.h
index 7e9164729..e67f1ccd2 100644
--- a/td/telegram/ContactsManager.h
+++ b/td/telegram/ContactsManager.h
@@ -185,6 +185,8 @@ class ContactsManager final : public Actor {
   int32 get_secret_chat_layer(SecretChatId secret_chat_id) const;
   FolderId get_secret_chat_initial_folder_id(SecretChatId secret_chat_id) const;
 
+  void can_send_message_to_user(UserId user_id, Promise<Unit> &&promise);
+
   void on_imported_contacts(int64 random_id, Result<tl_object_ptr<telegram_api::contacts_importedContacts>> result);
 
   void on_deleted_contacts(const vector<UserId> &deleted_contact_user_ids);
diff --git a/td/telegram/Td.cpp b/td/telegram/Td.cpp
index 0efb4bc8c..2055e5087 100644
--- a/td/telegram/Td.cpp
+++ b/td/telegram/Td.cpp
@@ -6528,6 +6528,12 @@ void Td::on_request(uint64 id, td_api::setNewChatPrivacySettings &request) {
                                                      std::move(promise));
 }
 
+void Td::on_request(uint64 id, const td_api::canSendMessageToUser &request) {
+  CHECK_IS_USER();
+  CREATE_OK_REQUEST_PROMISE();
+  contacts_manager_->can_send_message_to_user(UserId(request.user_id_), std::move(promise));
+}
+
 void Td::on_request(uint64 id, td_api::setChatTitle &request) {
   CLEAN_INPUT_STRING(request.title_);
   CREATE_OK_REQUEST_PROMISE();
diff --git a/td/telegram/Td.h b/td/telegram/Td.h
index 899d47213..f3700db74 100644
--- a/td/telegram/Td.h
+++ b/td/telegram/Td.h
@@ -1059,6 +1059,8 @@ class Td final : public Actor {
 
   void on_request(uint64 id, td_api::setNewChatPrivacySettings &request);
 
+  void on_request(uint64 id, const td_api::canSendMessageToUser &request);
+
   void on_request(uint64 id, td_api::setChatTitle &request);
 
   void on_request(uint64 id, const td_api::setChatPhoto &request);
diff --git a/td/telegram/cli.cpp b/td/telegram/cli.cpp
index 6c815911e..80167349f 100644
--- a/td/telegram/cli.cpp
+++ b/td/telegram/cli.cpp
@@ -5449,6 +5449,10 @@ class CliClient final : public Actor {
       get_args(args, allow_new_chats_from_unknown_users);
       auto settings = td_api::make_object<td_api::newChatPrivacySettings>(allow_new_chats_from_unknown_users);
       send_request(td_api::make_object<td_api::setNewChatPrivacySettings>(std::move(settings)));
+    } else if (op == "csmtu") {
+      UserId user_id;
+      get_args(args, user_id);
+      send_request(td_api::make_object<td_api::canSendMessageToUser>(user_id));
     } else if (op == "sct") {
       ChatId chat_id;
       string title;