Allow adding up to 10 accounts

Also warn when adding more than 3 accounts.

Telegram/Resources/langs/lang.strings

@@ -2556,5 +2556,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 "ktg_channel_status_not_in" = "not subscribed";
 "ktg_group_status_owner" = "is owner";
 "ktg_group_status_admin" = "is admin";
+"ktg_too_many_accounts_warning" = "Warning! Using too many accounts at the same time is not recommended due to higher memory comsumption and possible crashes because of it.\n\nYou sure you want to add a new account?";
+"ktg_account_add_anyway" = "Add anyway";
 
 // Keys finished

Telegram/Resources/langs/rewrites/ru.json

@@ -147,5 +147,7 @@
 	"ktg_group_status_not_in": "не участник",
 	"ktg_channel_status_not_in": "не подписчик",
 	"ktg_group_status_owner": "вы владелец",
-	"ktg_group_status_admin": "вы админ"
+	"ktg_group_status_admin": "вы админ",
+	"ktg_too_many_accounts_warning": "Внимание! Использование слишком большого количества аккаунтов одновременно не рекомендуется из-за высокого потребления памяти, а также возможных вылетов из-за этого.\n\nВы точно хотите добавить новый аккаунт?",
+	"ktg_account_add_anyway": "Всё равно добавить"
 }

Telegram/SourceFiles/main/main_domain.h

@@ -30,7 +30,8 @@ public:
 		std::unique_ptr<Account> account;
 	};
 
-	static constexpr auto kMaxAccounts = 3;
+	static constexpr auto kMaxAccountsWarn = 3;
+	static constexpr auto kMaxAccounts = 10;
 
 	explicit Domain(const QString &dataName);
 	~Domain();

Telegram/SourceFiles/window/window_main_menu.cpp

@@ -760,6 +760,8 @@ void MainMenu::rebuildAccounts() {
 	_addAccount->toggle(
 		(count < Main::Domain::kMaxAccounts),
 		anim::type::instant);
+
+	_accountsCount = count;
 }
 
 not_null<Ui::SlideWrap<Ui::RippleButton>*> MainMenu::setupAddAccount(
@@ -797,7 +799,19 @@ not_null<Ui::SlideWrap<Ui::RippleButton>*> MainMenu::setupAddAccount(
 	}, button->lifetime());
 
 	const auto add = [=](MTP::Environment environment) {
-		Core::App().domain().addActivated(environment);
+		const auto sure = [=] {
+			Core::App().domain().addActivated(environment);
+		};
+		if (_accountsCount >= Main::Domain::kMaxAccountsWarn) {
+			Ui::show(
+				Box<ConfirmBox>(
+					tr::ktg_too_many_accounts_warning(tr::now),
+					tr::ktg_account_add_anyway(tr::now),
+					sure),
+				Ui::LayerOption::KeepOther);
+		} else {
+			sure();
+		}
 	};
 
 	button->setAcceptBoth(true);

Telegram/SourceFiles/window/window_main_menu.h

@@ -82,6 +82,7 @@ private:
 		not_null<Main::Account*>,
 		base::unique_qptr<AccountButton>> _watched;
 	not_null<Ui::SlideWrap<Ui::VerticalLayout>*> _accounts;
+	int _accountsCount = 0;
 	Ui::SlideWrap<Ui::RippleButton> *_addAccount = nullptr;
 	not_null<Ui::SlideWrap<Ui::PlainShadow>*> _shadow;
 	not_null<Ui::Menu*> _menu;