Allow several accounts in Core::App.

Telegram/SourceFiles/main/main_accounts.h

@@ -0,0 +1,61 @@
+/*
+This file is part of Telegram Desktop,
+the official desktop application for the Telegram messaging service.
+
+For license and copyright information please follow this link:
+https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
+*/
+#pragma once
+
+namespace Storage {
+class Accounts;
+enum class StartResult : uchar;
+} // namespace Storage
+
+namespace Main {
+
+class Account;
+class Session;
+
+class Accounts final {
+public:
+	explicit Accounts(const QString &dataName);
+	~Accounts();
+
+	[[nodiscard]] bool started() const;
+	Storage::StartResult start(const QByteArray &passcode);
+
+	[[nodiscard]] Storage::Accounts &local() const {
+		return *_local;
+	}
+
+	[[nodiscard]] auto list() const
+		-> const base::flat_map<int, std::unique_ptr<Account>> &;
+	[[nodiscard]] rpl::producer<Account*> activeValue() const;
+
+	// Expects(started());
+	[[nodiscard]] Account &active() const;
+	[[nodiscard]] rpl::producer<not_null<Account*>> activeChanges() const;
+
+	[[nodiscard]] rpl::producer<Session*> activeSessionValue() const;
+	[[nodiscard]] rpl::producer<Session*> activeSessionChanges() const;
+
+	[[nodiscard]] int add();
+	void activate(int index);
+
+private:
+	const QString _dataName;
+	const std::unique_ptr<Storage::Accounts> _local;
+
+	base::flat_map<int, std::unique_ptr<Account>> _accounts;
+	rpl::variable<Account*> _active = nullptr;
+	int _activeIndex = 0;
+
+	rpl::event_stream<Session*> _activeSessions;
+
+	rpl::lifetime _activeLifetime;
+	rpl::lifetime _lifetime;
+
+};
+
+} // namespace Main