tell users how many in lobby on join/leave

src/server/message.go

@@ -1,9 +1,10 @@
 package server
 
 type message struct {
-	Text     string
-	Pitch    int
-	Rate     float64
-	VoiceIdx int
-	room     string
+	Text      string
+	QuietText string
+	Pitch     int
+	Rate      float64
+	VoiceIdx  int
+	room      string
 }

src/server/server.go

@@ -1,6 +1,7 @@
 package server
 
 import (
+	"fmt"
 	"log"
 	"net/http"
 )
@@ -31,9 +32,6 @@ func (s *Server) WS(w http.ResponseWriter, r *http.Request) error {
 	}
 	defer sess.Close()
 
-	log.Println("someone has joined", sess.room)
-	defer log.Println("someone has left", sess.room)
-
 	sess.cb = func(m message) error {
 		for i := range s.sessions {
 			if s.sessions[i].id != sess.id && s.sessions[i].room == sess.room {
@@ -46,8 +44,42 @@ func (s *Server) WS(w http.ResponseWriter, r *http.Request) error {
 		return nil
 	}
 
-	s.sessions = append(s.sessions, sess)
+	func() {
+		s.sessions = append(s.sessions, sess)
+
+		n := 0
+		for i := range s.sessions {
+			if s.sessions[i].room == sess.room {
+				n += 1
+			}
+		}
+		for i := range s.sessions {
+			if s.sessions[i].room == sess.room {
+				if s.sessions[i].id == sess.id {
+					s.sessions[i].scatterc <- message{QuietText: fmt.Sprintf("you have joined %v people", n-1)}
+				} else {
+					s.sessions[i].scatterc <- message{QuietText: fmt.Sprintf("there is now %v people", n)}
+				}
+			}
+		}
+	}()
 	defer func() {
+		n := 0
+		for i := range s.sessions {
+			if s.sessions[i].room == sess.room {
+				n += 1
+			}
+		}
+		n -= 1
+		for i := range s.sessions {
+			if s.sessions[i].room == sess.room {
+				if s.sessions[i].id == sess.id {
+				} else {
+					s.sessions[i].scatterc <- message{QuietText: fmt.Sprintf("there is now %v people", n)}
+				}
+			}
+		}
+
 		for i := range s.sessions {
 			if s.sessions[i].id == sess.id {
 				s.sessions = append(s.sessions[:i], s.sessions[i+1:]...)