From 7715044d66f7f5a6252206cd8e6c102fb4088b66 Mon Sep 17 00:00:00 2001
From: "." <.@.>
Date: Sun, 8 May 2016 13:43:22 +1200
Subject: [PATCH] client tag sync (via CTCP VERSION as a surrogate user)

--HG--
branch : nmdc-ircfrontend
---
 TODO.txt  |  2 --
 server.go | 38 ++++++++++++++++++++++++++++++++++----
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/TODO.txt b/TODO.txt
index 139365a..1b69493 100644
--- a/TODO.txt
+++ b/TODO.txt
@@ -7,8 +7,6 @@ WISHLIST
 
 - automatic markdown bold/italic formatting
 
-- client version sync (CTCP VERSION)
-
 - support changing nick (via reconnecting)
 
 - support USERHOST (used by androirc)
diff --git a/server.go b/server.go
index 7ac0fae..994d7ec 100644
--- a/server.go
+++ b/server.go
@@ -51,6 +51,8 @@ type Server struct {
 
 	verbose  bool
 	autojoin bool
+
+	sentCtcpVersion bool
 }
 
 func NewServer(name string, upstream libnmdc.HubAddress, conn net.Conn) *Server {
@@ -244,6 +246,12 @@ func (s *Server) upstreamWorker() {
 				} else {
 					// nick!username@userhost, but for us all three of those are always identical
 					s.reply(rplMsg, hubEvent.Nick+"!"+hubEvent.Nick+"@"+hubEvent.Nick, BLESSED_CHANNEL, reformatIncomingMessageBody(hubEvent.Message))
+
+					if !s.sentCtcpVersion {
+						// Abuse this first username in order to also send a CTCP version request
+						s.reply(rplMsg, hubEvent.Nick+"!"+hubEvent.Nick+"@"+hubEvent.Nick, BLESSED_CHANNEL, "\x01VERSION\x01")
+						s.sentCtcpVersion = true
+					}
 				}
 
 			case libnmdc.EVENT_SYSTEM_MESSAGE_FROM_CONN, libnmdc.EVENT_SYSTEM_MESSAGE_FROM_HUB:
@@ -346,10 +354,6 @@ func (s *Server) handleCommand(command string, args []string) {
 			s.handleCommand("JOIN", []string{BLESSED_CHANNEL})
 		}
 
-		// Send a CTCP VERSION request to the client. If the IRC client can
-		//   supply a client version string, we can replace our tag with it,
-		//   but that's optional
-
 	default:
 		s.handleRegisteredCommand(command, args)
 	}
@@ -413,6 +417,24 @@ func (s *Server) handleRegisteredCommand(command string, args []string) {
 	}
 }
 
+func (s *Server) SetClientSoftwareVersion(ver string) {
+	// "HexChat 2.12.1 [x64] / Microsoft Windows 10 Pro (x64) [Intel(R) Core(TM) i5-2500 CPU @ 3.30GHz (3.60GHz)]"
+	// A bit long and unwieldy. Heuristic: stop after the first word containing digits
+
+	parts := regexp.MustCompilePOSIX("^([^0-9]*[0-9]+[^ ]*) ").FindStringSubmatch(ver)
+
+	if len(parts) > 0 {
+		ver = strings.TrimRight(parts[0], " ")
+	}
+
+	s.verbosef("Replacing client tag with '%s'...", ver)
+
+	s.upstreamLauncher.Self.ClientTag = ver
+	s.upstream.Hco.Self.ClientTag = ver
+
+	s.upstream.SayInfo()
+}
+
 func (s *Server) handleJoinedCommand(command string, args []string) {
 
 	if s.clientState != CSJoined {
@@ -446,6 +468,14 @@ func (s *Server) handleJoinedCommand(command string, args []string) {
 
 		message := strings.Join(args[1:], " ")[1:] // strip leading colon
 
+		if strings.HasPrefix(message, "\x01VERSION ") {
+			// Not a real message - a reply to our internal request. Change the user's tag to match the actual client software
+			versionString := message[9:]
+			versionString = versionString[:len(versionString)-1]
+			s.SetClientSoftwareVersion(versionString)
+			return
+		}
+
 		if strings.HasPrefix(message, "\x01ACTION ") {
 			message = "/me " + message[8:]
 			message = message[:len(message)-1] // trailing \x01