From 3ff033cdf3b5bc49101e983592a79f44902f36e7 Mon Sep 17 00:00:00 2001
From: Kirsan <suker@nm.ru>
Date: Fri, 30 Mar 2018 18:36:31 +0300
Subject: [PATCH] Fix for
 https://github.com/telegramdesktop/tdesktop/issues/4544

(cherry picked from commit d99c757d44d7c31fbb0eb290f273ad4d2d464255)
---
 .../platform/win/main_window_win.cpp          | 22 +++++++++++++------
 .../platform/win/main_window_win.h            |  3 +++
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/Telegram/SourceFiles/platform/win/main_window_win.cpp b/Telegram/SourceFiles/platform/win/main_window_win.cpp
index 93bc5c4ae..8495050ef 100644
--- a/Telegram/SourceFiles/platform/win/main_window_win.cpp
+++ b/Telegram/SourceFiles/platform/win/main_window_win.cpp
@@ -873,7 +873,9 @@ void MainWindow::updateSystemMenu(Qt::WindowState state) {
 }
 
 void MainWindow::psUpdateMargins() {
-	if (!ps_hWnd) return;
+	if (!ps_hWnd || _inUpdateMargins) return;
+
+	_inUpdateMargins = true;
 
 	RECT r, a;
 
@@ -898,13 +900,18 @@ void MainWindow::psUpdateMargins() {
 
 		_deltaLeft = w.left - m.left;
 		_deltaTop = w.top - m.top;
+		_deltaRight = m.right - w.right;
+		_deltaBottom = m.bottom - w.bottom;
 
-		margins.setLeft(margins.left() - w.left + m.left);
-		margins.setRight(margins.right() - m.right + w.right);
-		margins.setBottom(margins.bottom() - m.bottom + w.bottom);
-		margins.setTop(margins.top() - w.top + m.top);
-	} else {
-		_deltaLeft = _deltaTop = 0;
+		margins.setLeft(margins.left() - _deltaLeft);
+		margins.setRight(margins.right() - _deltaRight);
+		margins.setBottom(margins.bottom() - _deltaBottom);
+		margins.setTop(margins.top() - _deltaTop);
+	} else if (_deltaLeft != 0 || _deltaTop != 0 || _deltaRight != 0 || _deltaBottom != 0) {
+		RECT w;
+		GetWindowRect(ps_hWnd, &w);
+		SetWindowPos(ps_hWnd, 0, 0, 0, w.right - w.left - _deltaLeft - _deltaRight, w.bottom - w.top - _deltaBottom - _deltaTop, SWP_NOMOVE | SWP_NOSENDCHANGING | SWP_NOZORDER | SWP_NOACTIVATE | SWP_NOREPOSITION);
+		_deltaLeft = _deltaTop = _deltaRight = _deltaBottom = 0;
 	}
 
 	QPlatformNativeInterface *i = QGuiApplication::platformNativeInterface();
@@ -918,6 +925,7 @@ void MainWindow::psUpdateMargins() {
 			}
 		}
 	}
+	_inUpdateMargins = false;
 }
 
 HWND MainWindow::psHwnd() const {
diff --git a/Telegram/SourceFiles/platform/win/main_window_win.h b/Telegram/SourceFiles/platform/win/main_window_win.h
index 96858cbb3..5bba35806 100644
--- a/Telegram/SourceFiles/platform/win/main_window_win.h
+++ b/Telegram/SourceFiles/platform/win/main_window_win.h
@@ -103,6 +103,7 @@ private:
 
 	bool _shadowsWorking = false;
 	bool _themeInited = false;
+	bool _inUpdateMargins = false;
 
 	HWND ps_hWnd = nullptr;
 	HWND ps_tbHider_hWnd = nullptr;
@@ -113,6 +114,8 @@ private:
 
 	int _deltaLeft = 0;
 	int _deltaTop = 0;
+	int _deltaRight = 0;
+	int _deltaBottom = 0;
 
 };