caps: Add message-tags draft capability

CHANGELOG.md

@@ -13,7 +13,7 @@ Improved compatibility, more features, etc.
 
 ### Added
 * Added integrated help.
-* Support for IRCv3 capability [`account-notify`](http://ircv3.net/specs/extensions/account-notify-3.1.html)
+* Support for IRCv3 capability [`account-notify`](http://ircv3.net/specs/extensions/account-notify-3.1.html), and draft capability [`message-tags`](http://ircv3.net/specs/core/message-tags-3.3.html) as `draft/message-tags`.
 
 ### Changed
 * Casemapping changed from custom unicode mapping to preliminary [rfc7700](https://github.com/ircv3/ircv3-specifications/pull/272) mapping.

irc/capability.go

@@ -18,6 +18,7 @@ const (
 	AccountNotify   Capability = "account-notify"
 	AwayNotify      Capability = "away-notify"
 	ExtendedJoin    Capability = "extended-join"
+	MessageTags     Capability = "draft/message-tags"
 	MultiPrefix     Capability = "multi-prefix"
 	SASL            Capability = "sasl"
 	ServerTime      Capability = "server-time"
@@ -30,6 +31,7 @@ var (
 		AccountNotify:   true,
 		AwayNotify:      true,
 		ExtendedJoin:    true,
+		MessageTags:     true,
 		MultiPrefix:     true,
 		SASL:            true,
 		ServerTime:      true,

irc/channel.go

@@ -10,6 +10,8 @@ import (
 	"log"
 	"strconv"
 	"time"
+
+	"github.com/DanielOaks/girc-go/ircmsg"
 )
 
 type Channel struct {
@@ -300,7 +302,7 @@ func (channel *Channel) CanSpeak(client *Client) bool {
 	return true
 }
 
-func (channel *Channel) PrivMsg(client *Client, message string) {
+func (channel *Channel) PrivMsg(clientOnlyTags *map[string]ircmsg.TagValue, client *Client, message string) {
 	if !channel.CanSpeak(client) {
 		client.Send(nil, client.server.name, ERR_CANNOTSENDTOCHAN, channel.name, "Cannot send to channel")
 		return
@@ -309,9 +311,13 @@ func (channel *Channel) PrivMsg(client *Client, message string) {
 		if member == client {
 			continue
 		}
+		if member.capabilities[MessageTags] {
+			member.SendFromClient(client, clientOnlyTags, client.nickMaskString, "PRIVMSG", channel.name, message)
+		} else {
 			member.SendFromClient(client, nil, client.nickMaskString, "PRIVMSG", channel.name, message)
 		}
 	}
+}
 
 func (channel *Channel) applyModeFlag(client *Client, mode ChannelMode,
 	op ModeOp) bool {

irc/message_tags.go

@@ -0,0 +1,23 @@
+// Copyright (c) 2016- Daniel Oaks <daniel@danieloaks.net>
+// released under the MIT license
+
+package irc
+
+import "github.com/DanielOaks/girc-go/ircmsg"
+
+// GetClientOnlyTags tags a tag map, and returns a map containing just the client-only tags from it.
+func GetClientOnlyTags(tags map[string]ircmsg.TagValue) *map[string]ircmsg.TagValue {
+	if len(tags) < 1 {
+		return nil
+	}
+
+	clientOnlyTags := make(map[string]ircmsg.TagValue)
+
+	for name, value := range tags {
+		if len(name) > 1 && name[0] == '+' {
+			clientOnlyTags[name] = value
+		}
+	}
+
+	return &clientOnlyTags
+}

irc/server.go

@@ -567,6 +567,7 @@ func topicHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 
 // PRIVMSG <target>{,<target>} <message>
 func privmsgHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
+	clientOnlyTags := GetClientOnlyTags(msg.Tags)
 	targets := strings.Split(msg.Params[0], ",")
 	message := msg.Params[1]
 
@@ -578,7 +579,7 @@ func privmsgHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool
 				client.Send(nil, server.name, ERR_NOSUCHCHANNEL, client.nick, targetString, "No such channel")
 				continue
 			}
-			channel.PrivMsg(client, message)
+			channel.PrivMsg(clientOnlyTags, client, message)
 		} else {
 			target, err = CasefoldName(targetString)
 			user := server.clients.Get(target)
@@ -586,7 +587,10 @@ func privmsgHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool
 				client.Send(nil, server.name, ERR_NOSUCHNICK, target, "No such nick")
 				continue
 			}
-			user.Send(nil, client.nickMaskString, "PRIVMSG", user.nick, message)
+			if !user.capabilities[MessageTags] {
+				clientOnlyTags = nil
+			}
+			user.Send(clientOnlyTags, client.nickMaskString, "PRIVMSG", user.nick, message)
 			if user.flags[Away] {
 				//TODO(dan): possibly implement cooldown of away notifications to users
 				client.Send(nil, server.name, RPL_AWAY, user.nick, user.awayMessage)
@@ -852,6 +856,7 @@ func motdHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 
 // NOTICE <target>{,<target>} <message>
 func noticeHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
+	clientOnlyTags := GetClientOnlyTags(msg.Tags)
 	targets := strings.Split(msg.Params[0], ",")
 	message := msg.Params[1]
 
@@ -863,7 +868,7 @@ func noticeHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 				// errors silently ignored with NOTICE as per RFC
 				continue
 			}
-			channel.PrivMsg(client, message)
+			channel.PrivMsg(clientOnlyTags, client, message)
 		} else {
 			target, err := CasefoldName(targetString)
 			if err != nil {
@@ -875,7 +880,10 @@ func noticeHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 				// errors silently ignored with NOTICE as per RFC
 				continue
 			}
-			user.Send(nil, client.nickMaskString, "NOTICE", user.nick, message)
+			if !user.capabilities[MessageTags] {
+				clientOnlyTags = nil
+			}
+			user.Send(clientOnlyTags, client.nickMaskString, "NOTICE", user.nick, message)
 		}
 	}
 	return false