From 6882093ed1e37eff23ecc0c7af92ee088e3f02b9 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Tue, 7 Apr 2020 15:19:52 +0400
Subject: [PATCH] Send init connection params.

---
 .../SourceFiles/mtproto/session_private.cpp   | 26 +++++++++++++++++--
 .../SourceFiles/mtproto/session_private.h     |  1 +
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/Telegram/SourceFiles/mtproto/session_private.cpp b/Telegram/SourceFiles/mtproto/session_private.cpp
index f26e7c5d9a..1b61590034 100644
--- a/Telegram/SourceFiles/mtproto/session_private.cpp
+++ b/Telegram/SourceFiles/mtproto/session_private.cpp
@@ -482,6 +482,27 @@ mtpMsgId SessionPrivate::placeToContainer(
 	return msgId;
 }
 
+MTPVector<MTPJSONObjectValue> SessionPrivate::prepareInitParams() {
+	const auto local = QDateTime::currentDateTime();
+	const auto utc = QDateTime(local.date(), local.time(), Qt::UTC);
+	const auto shift = base::unixtime::now() - (TimeId)::time(nullptr);
+	const auto delta = int(utc.toTime_t()) - int(local.toTime_t()) - shift;
+	auto sliced = delta;
+	while (sliced < -12 * 3600) {
+		sliced += 24 * 3600;
+	}
+	while (sliced > 14 * 3600) {
+		sliced -= 24 * 3600;
+	}
+	const auto sign = (sliced < 0) ? -1 : 1;
+	const auto rounded = std::round(std::abs(sliced) / 900.) * 900 * sign;
+	return MTP_vector<MTPJSONObjectValue>(
+		1,
+		MTP_jsonObjectValue(
+			MTP_string("tz_offset"),
+			MTP_jsonNumber(MTP_double(rounded))));
+}
+
 void SessionPrivate::tryToSend() {
 	DEBUG_LOG(("MTP Info: tryToSend for dc %1.").arg(_shiftedDcId));
 	if (!_connection) {
@@ -612,7 +633,8 @@ void SessionPrivate::tryToSend() {
 			: MTPInputClientProxy();
 		using Flag = MTPInitConnection<SerializedRequest>::Flag;
 		initWrapper = MTPInitConnection<SerializedRequest>(
-			MTP_flags(mtprotoProxy ? Flag::f_proxy : Flag(0)),
+			MTP_flags(Flag::f_params
+				| (mtprotoProxy ? Flag::f_proxy : Flag(0))),
 			MTP_int(ApiId),
 			MTP_string(deviceModel),
 			MTP_string(systemVersion),
@@ -621,7 +643,7 @@ void SessionPrivate::tryToSend() {
 			MTP_string(langPackName),
 			MTP_string(cloudLangCode),
 			clientProxyFields,
-			MTPJSONValue(), // #TODO polls timezone
+			MTP_jsonObject(prepareInitParams()),
 			SerializedRequest());
 		initSizeInInts = (tl::count_length(initWrapper) >> 2) + 2;
 		initSize = initSizeInInts * sizeof(mtpPrime);
diff --git a/Telegram/SourceFiles/mtproto/session_private.h b/Telegram/SourceFiles/mtproto/session_private.h
index 91cfe4c616..fe39450f27 100644
--- a/Telegram/SourceFiles/mtproto/session_private.h
+++ b/Telegram/SourceFiles/mtproto/session_private.h
@@ -166,6 +166,7 @@ private:
 	[[nodiscard]] uint32 nextRequestSeqNumber(bool needAck);
 
 	[[nodiscard]] bool realDcTypeChanged();
+	[[nodiscard]] MTPVector<MTPJSONObjectValue> prepareInitParams();
 
 	const not_null<Instance*> _instance;
 	const ShiftedDcId _shiftedDcId = 0;