Make calls command concurrent, also update README

README.md

@@ -1,3 +1,10 @@
 # stillbox
 
-A Golang scanner call server, with the Calls webapp.
+A Golang scanner call server (`gordio`), with the Calls webapp.
+
+**NOTE**
+
+If this message is still here, the database schema *initial migration* and protobuf definitions are **still subject to change**.
+
+Once `gordio` is actually usable (but not necessarily feature-complete), I will remove this note, and start using DB migrations and
+protobuf best practices (i.e. not changing field numbers).

cmd/calls/audio.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"log"
 	"time"
 
 	"dynatron.me/x/go-minimp3"
@@ -9,17 +10,24 @@ import (
 )
 
 type Player struct {
+	c          chan playReq
 	ctx        *oto.Context
 	sampleRate int
 	channels   int
 }
 
 func NewPlayer() *Player {
-	p := &Player{}
+	p := &Player{
+		c: make(chan playReq, 256),
+	}
 
 	return p
 }
 
+func (p *Player) Queue() int {
+	return len(p.c)
+}
+
 func (p *Player) initOto(samp, channels int) error {
 	if samp != p.sampleRate || channels != p.channels {
 		if p.ctx != nil {
@@ -64,15 +72,45 @@ func (p *Player) playMP3(audio []byte) error {
 	return nil
 }
 
-func (p *Player) Play(audio []byte, mimeType string) error {
-	switch mimeType {
+type playReq struct {
+	audio    []byte
+	mimeType string
+}
+
+func (p *Player) Play(audio []byte, mimeType string) {
+	p.c <- playReq{audio, mimeType}
+}
+
+func (p *Player) play(req playReq) error {
+	switch req.mimeType {
 	case "audio/mpeg":
-		return p.playMP3(audio)
+		return p.playMP3(req.audio)
 	case "audio/wav":
 		panic("wav not implemented yet")
 	default:
-		return fmt.Errorf("unknown format %s", mimeType)
+		return fmt.Errorf("unknown format %s", req.mimeType)
+	}
+}
+
+func (p *Player) Go(done <-chan struct{}) {
+	for {
+		select {
+		case <-done:
+			close(p.c)
+			p.ctx.Close()
+			return
+		case r, ok := <-p.c:
+			if !ok {
+				p.ctx.Close()
+				return
+			}
+
+			fmt.Printf("> [Q: %d]\r", p.Queue())
+			err := p.play(r)
+			fmt.Printf("\033[2K")
+			if err != nil {
+				log.Println(err)
+			}
+		}
 	}
-
-	return nil
 }

cmd/calls/main.go

@@ -81,6 +81,10 @@ func main() {
 	log.Printf("connected")
 
 	done := make(chan struct{})
+	playDone := make(chan struct{})
+
+	go play.Go(playDone)
+	defer close(playDone)
 
 	go func() {
 		defer close(done)
@@ -101,11 +105,8 @@ func main() {
 
 				switch v := m.ToClientMessage.(type) {
 				case *pb.Message_Call:
-					log.Printf("call tg %d", v.Call.Talkgroup)
-					err := play.Play(v.Call.Audio, v.Call.AudioType)
-					if err != nil {
-						log.Println(err)
-					}
+					log.Printf("call tg %d [Q: %d]", v.Call.Talkgroup, play.Queue())
+					play.Play(v.Call.Audio, v.Call.AudioType)
 				case *pb.Message_Notification:
 					log.Println(v.Notification.Msg)
 				default: