WindowServer/LibGUI: Allow windows to set minimum size

userspace/libraries/LibGUI/Window.cpp

@@ -306,6 +306,16 @@ namespace LibGUI
 			return on_socket_error(__FUNCTION__);
 	}
 
+	void Window::set_min_size(uint32_t width, uint32_t height)
+	{
+		WindowPacket::WindowSetMinSize packet;
+		packet.width = width;
+		packet.height = height;
+
+		if (auto ret = packet.send_serialized(m_server_fd); ret.is_error())
+			return on_socket_error(__FUNCTION__);
+	}
+
 	void Window::set_attributes(Attributes attributes)
 	{
 		WindowPacket::WindowSetAttributes packet;

userspace/libraries/LibGUI/include/LibGUI/Packet.h

@@ -164,6 +164,7 @@ namespace LibGUI
 		WindowSetAttributes,
 		WindowSetMouseCapture,
 		WindowSetSize,
+		WindowSetMinSize,
 		WindowSetFullscreen,
 		WindowSetTitle,
 
@@ -227,6 +228,12 @@ namespace LibGUI
 			uint32_t, height
 		);
 
+		DEFINE_PACKET(
+			WindowSetMinSize,
+			uint32_t, width,
+			uint32_t, height
+		);
+
 		DEFINE_PACKET(
 			WindowSetFullscreen,
 			bool, fullscreen

userspace/libraries/LibGUI/include/LibGUI/Window.h

@@ -76,6 +76,8 @@ namespace LibGUI
 		Attributes get_attributes() const { return m_attributes; }
 		void set_attributes(Attributes attributes);
 
+		void set_min_size(uint32_t width, uint32_t height);
+
 		// send resize request to window server
 		// actual resize is only done after resize callback is called
 		void request_resize(uint32_t width, uint32_t height);

userspace/programs/WindowServer/Window.h

@@ -52,6 +52,9 @@ public:
 	LibGUI::Window::Attributes get_attributes() const { return m_attributes; };
 	void set_attributes(LibGUI::Window::Attributes attributes) { m_attributes = attributes; };
 
+	Rectangle get_min_size() const { return m_min_size; }
+	void set_min_size(Rectangle min_size) { m_min_size = min_size.get_bounding_box({ 0, 0, m_title_bar_height, 0 }); }
+
 	BAN::ErrorOr<void> set_title(BAN::StringView title) { m_title.clear(); TRY(m_title.append(title)); TRY(prepare_title_bar()); return {}; }
 
 	const uint32_t* framebuffer() const { return m_fb_addr; }
@@ -84,6 +87,7 @@ private:
 
 	const int   m_client_fd      { -1 };
 	Rectangle   m_client_area    { 0, 0, 0, 0 };
+	Rectangle   m_min_size       { 0, 0, m_title_bar_height, 0 };
 	long        m_smo_key        { 0 };
 	uint32_t*   m_fb_addr        { nullptr };
 	BAN::String m_title;

userspace/programs/WindowServer/WindowServer.cpp

@@ -261,6 +261,26 @@ void WindowServer::on_window_set_size(int fd, const LibGUI::WindowPacket::Window
 	invalidate(target_window->full_area().get_bounding_box(old_area));
 }
 
+void WindowServer::on_window_set_min_size(int fd, const LibGUI::WindowPacket::WindowSetMinSize& packet)
+{
+	BAN::RefPtr<Window> target_window;
+	for (auto& window : m_client_windows)
+	{
+		if (window->client_fd() != fd)
+			continue;
+		target_window = window;
+		break;
+	}
+
+	if (!target_window)
+	{
+		dwarnln("client tried to set window min size while not owning a window");
+		return;
+	}
+
+	target_window->set_min_size({ 0, 0, static_cast<int32_t>(packet.width), static_cast<int32_t>(packet.height) });
+}
+
 void WindowServer::on_window_set_fullscreen(int fd, const LibGUI::WindowPacket::WindowSetFullscreen& packet)
 {
 	if (m_state == State::Fullscreen)
@@ -1173,15 +1193,17 @@ Rectangle WindowServer::cursor_area() const
 
 Rectangle WindowServer::resize_area(Position cursor) const
 {
+	const auto min_size = m_focused_window->get_min_size();
+
 	int32_t diff_x = m_resize_start.x - cursor.x;
 	if (m_resize_quadrant % 2)
 		diff_x = -diff_x;
-	diff_x = BAN::Math::max(diff_x, -m_focused_window->client_width() + 20);
+	diff_x = BAN::Math::max(diff_x, -m_focused_window->client_width() + min_size.width);
 
 	int32_t diff_y = m_resize_start.y - cursor.y;
 	if (m_resize_quadrant / 2)
 		diff_y = -diff_y;
-	diff_y = BAN::Math::max(diff_y, -m_focused_window->client_height() + 20);
+	diff_y = BAN::Math::max(diff_y, -m_focused_window->client_height() + min_size.height);
 
 	int32_t off_x = 0;
 	if (m_resize_quadrant % 2 == 0)

userspace/programs/WindowServer/WindowServer.h

@@ -37,6 +37,7 @@ public:
 	void on_window_set_attributes(int fd, const LibGUI::WindowPacket::WindowSetAttributes&);
 	void on_window_set_mouse_capture(int fd, const LibGUI::WindowPacket::WindowSetMouseCapture&);
 	void on_window_set_size(int fd, const LibGUI::WindowPacket::WindowSetSize&);
+	void on_window_set_min_size(int fd, const LibGUI::WindowPacket::WindowSetMinSize&);
 	void on_window_set_fullscreen(int fd, const LibGUI::WindowPacket::WindowSetFullscreen&);
 	void on_window_set_title(int fd, const LibGUI::WindowPacket::WindowSetTitle&);
 

userspace/programs/WindowServer/main.cpp

@@ -375,6 +375,10 @@ int main()
 						if (auto ret = LibGUI::WindowPacket::WindowSetSize::deserialize(client_data.packet_buffer.span()); !ret.is_error())
 							window_server.on_window_set_size(fd, ret.release_value());
 						break;
+					case LibGUI::PacketType::WindowSetMinSize:
+						if (auto ret = LibGUI::WindowPacket::WindowSetMinSize::deserialize(client_data.packet_buffer.span()); !ret.is_error())
+							window_server.on_window_set_min_size(fd, ret.release_value());
+						break;
 					case LibGUI::PacketType::WindowSetFullscreen:
 						if (auto ret = LibGUI::WindowPacket::WindowSetFullscreen::deserialize(client_data.packet_buffer.span()); !ret.is_error())
 							window_server.on_window_set_fullscreen(fd, ret.release_value());