major: fixed bug in joinchannel, added INVITE command

go.mod

@@ -2,4 +2,7 @@ module ircserve
 
 go 1.26.3
 
-require github.com/ergochat/irc-go v0.6.0
+require (
+	github.com/ergochat/irc-go v0.6.0
+	github.com/mattn/go-sqlite3 v1.14.48
+)

go.sum

@@ -1,2 +1,4 @@
 github.com/ergochat/irc-go v0.6.0 h1:Y0AGV76aeihJfCtLaQh+OyJKFiKGrYC0VTkeMZ6XW28=
 github.com/ergochat/irc-go v0.6.0/go.mod h1:2vi7KNpIPWnReB5hmLpl92eMywQvuIeIIGdt/FQCph0=
+github.com/mattn/go-sqlite3 v1.14.48 h1:7XHIgl0a8HwOaiK4E47ozLkST78rR9+OtNGx27D/TFs=
+github.com/mattn/go-sqlite3 v1.14.48/go.mod h1:6JTjA44L93a0QCyJef5YvlPoKXntQPjzWv5gtm9sB6w=

main.go

@@ -171,19 +171,25 @@ func handleConn(conn net.Conn) {
 					client.fwrite(":server 433 * %s :Nickname is already in use\r\n", newNick)
 				} else {
 					oldNick := client.nick
-					if oldNick != "" {
+					client.nick = newNick
-						// nick change
+
 					cliMu.Lock()
+					if oldNick != "" {
 						delete(clients, oldNick)
+					}
 					clients[newNick] = client
 					cliMu.Unlock()
 					for _, ch := range client.channels {
 						ch.mu.Lock()
+						if oldNick != "" {
 							delete(ch.members, oldNick)
+						} else {
+							delete(ch.members, "")
+						}
 						ch.members[newNick] = client
 						ch.mu.Unlock()
 					}
-						client.nick = newNick
+					if oldNick != "" {
 						for _, ch := range client.channels {
 							broadcastNames(ch)
 						}
@@ -192,15 +198,12 @@ func handleConn(conn net.Conn) {
 								other.fwrite(":%s NICK %s\r\n", oldNick, newNick)
 							}
 						}
-					} else {
-						client.nick = newNick
-						cliMu.Lock()
-						clients[newNick] = client
-						cliMu.Unlock()
 					}
+
 					client.checkRegistration()
 				}
 			}
+
 		case "CAP":
 			if len(msg.Params) < 1 {
 				client.fwrite(":server 461 %s CAP :Not enough parameters\r\n", client.nick)
@@ -210,7 +213,7 @@ func handleConn(conn net.Conn) {
 			switch subcmd {
 			case "LS":
 				// explicitly tell we only support PLAIN SASL, as well as chathistory
-				client.fwrite(":server CAP * LS :sasl=PLAIN chathistory\r\n")
+				client.fwrite(":server CAP * LS :sasl=PLAIN sasl chathistory\r\n")
 
 			case "REQ":
 				if len(msg.Params) >= 2 && strings.Contains(strings.ToLower(msg.Params[1]), "sasl") {
@@ -335,6 +338,44 @@ func handleConn(conn net.Conn) {
 				text := msg.Params[1]
 				sendNotice(client, target, text)
 			}
+		case "INVITE":
+			if !client.registered {
+				client.sendUnregisteredNotice()
+				continue
+			}
+			if len(msg.Params) < 2 {
+				client.fwrite(":server 461 %s INVITE :Not enough parameters\r\n", client.nick)
+				continue
+			}
+			targetNick := msg.Params[0]
+			channelName := normalizeChannelName(msg.Params[1])
+
+			cliMu.RLock()
+			target, ok := clients[targetNick]
+			cliMu.RUnlock()
+			if !ok {
+				client.fwrite(":server 401 %s %s :No such nick\r\n", client.nick, targetNick)
+				continue
+			}
+
+			chMu.Lock()
+			ch, ok := channels[channelName]
+			chMu.Unlock()
+			if !ok {
+				client.fwrite(":server 403 %s %s :No such channel\r\n", client.nick, channelName)
+				continue
+			}
+
+			ch.mu.RLock()
+			_, inChannel := ch.members[client.nick]
+			ch.mu.RUnlock()
+			if !inChannel {
+				client.fwrite(":server 442 %s %s :You're not on that channel\r\n", client.nick, channelName)
+				continue
+			}
+			client.fwrite(":server 341 %s %s %s\r\n", client.nick, targetNick, channelName)
+			target.fwrite(":%s INVITE %s :%s\r\n", client.nick, targetNick, channelName)
+
 		case "QUIT":
 			if !client.registered {
 				client.sendUnregisteredNotice()
@@ -394,6 +435,7 @@ func handleConn(conn net.Conn) {
 			} else {
 				fmt.Fprintf(client.conn, ":server 461 %s NAMES :Not enough parameters\r\n", client.nick)
 			}
+			// ircv3 stuff
 		case "CHATHISTORY":
 			if len(msg.Params) < 3 {
 				client.fwrite(":server 461 %s CHATHISTORY :Not enough parameters\r\n", client.nick)
@@ -624,9 +666,10 @@ func handleMode(sender *Client, channelName, mode, targetNick string) {
 		sender.fwrite(":server 501 %s :Unknown MODE flag\r\n", sender.nick)
 	}
 }
-
 func joinChannel(c *Client, name string) {
 	name = normalizeChannelName(name)
+
+	// get or create channel
 	chMu.Lock()
 	ch, ok := channels[name]
 	if !ok {
@@ -634,13 +677,9 @@ func joinChannel(c *Client, name string) {
 			name:        name,
 			members:     make(map[string]*Client),
 			ops:         make(map[string]bool),
-			history:     nil,
 			description: "none",
 		}
 		channels[name] = ch
-		if globalOps[c.nick] {
-			ch.ops[c.nick] = true
-		}
 	}
 	if globalOps[c.nick] {
 		ch.ops[c.nick] = true
@@ -648,20 +687,47 @@ func joinChannel(c *Client, name string) {
 	chMu.Unlock()
 
 	ch.mu.Lock()
+	// reject duplicate join
+	if _, exists := ch.members[c.nick]; exists {
+		ch.mu.Unlock()
+		c.fwrite(":server 443 %s %s %s :is already on channel\r\n",
+			c.nick, c.nick, name)
+		return
+	}
+	// clean up stale empty nick
+	delete(ch.members, "")
+	// add new member
 	ch.members[c.nick] = c
 	c.channels[name] = ch
 	ch.mu.Unlock()
+
+	// echo JOIN to client
+	fmt.Fprintf(c.conn, ":%s JOIN %s\r\n", c.nick, name)
+	// broadcast JOIN to others
 	for _, member := range ch.members {
+		if member != c {
 			fmt.Fprintf(member.conn, ":%s JOIN %s\r\n", c.nick, name)
 		}
+	}
 
+	// topic
+	if ch.description != "" {
+		c.fwrite(":server 332 %s %s :%s\r\n", c.nick, name, ch.description)
+	} else {
+		c.fwrite(":server 331 %s %s :No topic is set\r\n", c.nick, name)
+	}
+
+	// names list
+	c.sendNames(ch)
+
+	// MODE if op
 	if ch.ops[c.nick] {
 		for _, member := range ch.members {
 			member.fwrite(":server MODE %s +o %s\r\n", name, c.nick)
 		}
 	}
-	c.sendNames(ch)
 }
+
 func (c *Client) partChannel(name string) {
 	chMu.Lock()
 	ch, ok := channels[name]
@@ -809,7 +875,7 @@ func storeMessage(ch *Channel, sender *Client, target, text string) {
 	msg := HistoryMessage{
 		MsgID:   fmt.Sprintf("%d", time.Now().UnixNano()),
 		Time:    time.Now(),
-		Prefix:  fmt.Sprintf("%s!%s@%s", sender.nick, sender.user, sender.host),
+		Prefix:  fmt.Sprintf("%s!%s@%s", sender.nick, sender.user, "host"), // for privacy reasons
 		Command: "PRIVMSG",
 		Params:  []string{target},
 		Text:    text,