From 1abc3f43f28462b6971390b7c5a28984f629231f Mon Sep 17 00:00:00 2001
From: 45Tatami <tatami@fftatami.cc>
Date: Wed, 24 May 2023 00:08:13 +0200
Subject: [PATCH] wip: feat: implement sending via multicast

---
 TCPSender/TCPSender.cpp | 54 +++++++++++++++++++++++++++++++++++++++++
 TCPSender/resource.h    |  3 ++-
 TCPSender/resource.rc   |  7 +++---
 3 files changed, 60 insertions(+), 4 deletions(-)

diff --git a/TCPSender/TCPSender.cpp b/TCPSender/TCPSender.cpp
index aeac0a4..9570f66 100644
--- a/TCPSender/TCPSender.cpp
+++ b/TCPSender/TCPSender.cpp
@@ -46,9 +46,11 @@ HWND win_hndl = NULL;
 UINT const WM_USR_LOG = WM_APP + 1;
 UINT const WM_USR_TOGGLE_CONNECT = WM_APP + 2;
 UINT const WM_USR_LOAD_CONFIG = WM_APP + 3;
+UINT const WM_USR_TOGGLE_MULTICAST = WM_APP + 4;
 
 HANDLE comm_thread;
 wstring remote = L"localhost:30501";
+wstring remote_multicast = L"239.80.123.4:30501";
 wstring config_file_path;
 
 // Mutex/cv protects following vars
@@ -122,6 +124,10 @@ void toggle_want_connect()
 	PostMessage(win_hndl, WM_USR_TOGGLE_CONNECT, (WPARAM) NULL, (LPARAM) NULL);
 }
 
+void toggle_multicast() {
+	PostMessage(win_hndl, WM_USR_TOGGLE_MULTICAST, (WPARAM) NULL, (LPARAM) NULL);
+}
+
 void save_config(path const& filepath, wstring const& remote, bool connect)
 {
 	std::wofstream f{filepath, std::ios_base::trunc};
@@ -242,6 +248,12 @@ INT_PTR CALLBACK DialogProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lPara
 
 			break;
 		}
+		case IDC_MULTI_BOX:
+		{
+			bool const checked = IsDlgButtonChecked(hWnd, IDC_MULTI_BOX);
+			toggle_multicast();
+			break;
+		}
 		default:
 			return false;
 		}
@@ -288,6 +300,23 @@ INT_PTR CALLBACK DialogProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lPara
 		conn_cv.notify_one();
 		return true;
 	}
+	case WM_USR_TOGGLE_MULTICAST:
+	{
+		lock_guard<mutex> conn_lk{ conn_mut };
+
+		want_connect = false;
+		// TODO wait for disconnect?
+
+		// off -> on
+		//      button set text "set"
+		//      text set saved multicast
+		//
+		// on -> off
+		//      button set text "Connect"
+		//      text set saved unicast
+
+		return true;
+	}
 	case WM_USR_LOAD_CONFIG:
 	{
 		lock_guard<mutex> conn_lk{ conn_mut };
@@ -422,6 +451,31 @@ SOCKET _connect() {
 	return sock;
 }
 
+SOCKET _connect_multic()
+{
+	SOCKET sock;
+
+	sock = socket(AF_INET, SOCK_DGRAM, 0);
+	// TODO fd < 0
+
+	string remote_ch =
+		wstring_convert<codecvt_utf8_utf16<wchar_t>>{}.to_bytes(remote_multicast);
+
+	auto pos = remote_ch.rfind(":");
+	string port_str = pos == string::npos ? "30501" : remote_ch.substr(pos + 1);
+	u_short port = std::stoul(port_str);
+
+	struct sockaddr_in addr = { 0 };
+	addr.sin_family = AF_INET;
+	addr.sin_addr.s_addr = inet_addr(remote_ch.c_str());
+	addr.sin_port = htons(port);
+
+	connect(sock, (struct sockaddr *) &addr, sizeof(addr));
+	// TODO return
+
+	return sock;
+}
+
 bool _send(SOCKET &sock, string const &msg) {
 	int len = (int) msg.length();
 	int buf_len = len + 4;
diff --git a/TCPSender/resource.h b/TCPSender/resource.h
index 907e8bd..f81d710 100644
--- a/TCPSender/resource.h
+++ b/TCPSender/resource.h
@@ -1257,6 +1257,7 @@
 #define IDC_BTN_SUBMIT2                 1002
 #define IDC_EDIT2                       1003
 #define IDC_LOG                         1003
+#define IDC_MULTI_BOX                   1004
 #define CF_GDIOBJLAST                   0x03FF
 #define _WIN32_WINNT_NT4                0x0400
 #define _WIN32_IE_IE40                  0x0400
@@ -1618,7 +1619,7 @@
 #ifndef APSTUDIO_READONLY_SYMBOLS
 #define _APS_NEXT_RESOURCE_VALUE        105
 #define _APS_NEXT_COMMAND_VALUE         40001
-#define _APS_NEXT_CONTROL_VALUE         1004
+#define _APS_NEXT_CONTROL_VALUE         1005
 #define _APS_NEXT_SYMED_VALUE           101
 #endif
 #endif
diff --git a/TCPSender/resource.rc b/TCPSender/resource.rc
index 3d43311..dd5c7c1 100644
--- a/TCPSender/resource.rc
+++ b/TCPSender/resource.rc
@@ -48,14 +48,15 @@ END
 // Dialog
 //
 
-IDD_DIALOG1 DIALOGEX 0, 0, 309, 177
+IDD_DIALOG1 DIALOGEX 0, 0, 309, 187
 STYLE DS_SETFONT | DS_MODALFRAME | DS_FIXEDSYS | WS_POPUP | WS_VISIBLE | WS_CAPTION
 CAPTION "TCP Sender"
 FONT 8, "MS Shell Dlg", 400, 0, 0x1
 BEGIN
-    EDITTEXT        IDC_REMOTE,7,7,228,14,ES_AUTOHSCROLL
+    EDITTEXT        IDC_REMOTE,7,13,228,14,ES_AUTOHSCROLL
     PUSHBUTTON      "Connect",IDC_BTN_SUBMIT,252,7,50,14,BS_CENTER
-    EDITTEXT        IDC_LOG,7,31,295,139,ES_MULTILINE | ES_AUTOVSCROLL | ES_READONLY
+    AUTOCHECKBOX    "Multicast",IDC_MULTI_BOX,255,24,228,14
+    EDITTEXT        IDC_LOG,7,41,295,139,ES_MULTILINE | ES_AUTOVSCROLL | ES_READONLY
 END