dndmusicbot/speaker/discord.go

package discordspeaker

import (
	"context"
	"fmt"
	"io"
	"log"
	"sync"
	"time"

	"github.com/diamondburned/arikawa/v3/voice"
	"github.com/diamondburned/arikawa/v3/voice/voicegateway"
	"github.com/gopxl/beep"
	"github.com/pkg/errors"
	"golang.org/x/time/rate"
	"gopkg.in/hraban/opus.v2"

	cc "github.com/tejzpr/ordered-concurrently/v3"
)

var (
	mu         sync.Mutex
	mixer      beep.Mixer
	samples    [][2]float64
	done       chan struct{}
	encoder    *opus.Encoder
	frameSize  int = 960
	channels   int = 2
	sampleRate int = 48000
	maxBytes   int = (frameSize * 2) * 2
	buf        []byte
	session    *voice.Session
	spk        bool
	input      chan cc.WorkFunction
	pw         *io.PipeWriter
	pr         *io.PipeReader
	spklimit   = rate.NewLimiter(rate.Every(2*time.Second), 1)
)

var Silence = [2]float64{}

func Init(dgv *voice.Session) error {
	var err error

	mu.Lock()
	defer mu.Unlock()
	Close()

	pr, pw = io.Pipe()
	buf = make([]byte, maxBytes)
	mixer = beep.Mixer{}
	samples = make([][2]float64, frameSize)

	session = dgv

	encoder, err = opus.NewEncoder(sampleRate, channels, opus.AppVoIP)
	encoder.SetBitrateToMax()

	if err != nil {
		return errors.Wrap(err, "failed to initialize speaker")
	}

	input = make(chan cc.WorkFunction)
	ctx := context.Background()
	output := cc.Process(ctx, input, &cc.Options{PoolSize: 4, OutChannelBuffer: 4})

	go func() {
		for {
			select {
			default:
				update()
			case out := <-output:
				fmt.Println(pw.Write(out.Value.([]byte)))
			case <-done:
				return
			}
		}
	}()

	go ReadSend()

	return nil
}

func ReadSend() {
	for {
		buf := make([]byte, maxBytes)
		n, err := pr.Read(buf)
		if err != nil {
			log.Println(err)
			return
		}
		_, err = session.Write(buf[:n])
		if err != nil {
			log.Println(err)
			return
		}
	}
}

func Close() {
}

func Lock() {
	mu.Lock()
}

// Unlock unlocks the speaker. Call after modifying any currently playing Streamer.
func Unlock() {
	mu.Unlock()
}

func Play(s ...beep.Streamer) {
	mu.Lock()
	mixer.Add(s...)
	mu.Unlock()
}

func Clear() {
	mu.Lock()
	mixer.Clear()
	mu.Unlock()
}

func Speak(s bool) {
	switch s {
	case true:

	case false:

	}

}

func update() {
	mu.Lock()
	mixer.Stream(samples)
	mu.Unlock()

	if IsSilent(samples) {
		if spk && spklimit.Allow() {
			log.Println("Notspeaking")
			session.Speaking(context.Background(), voicegateway.NotSpeaking)
			spk = false
		}

		return
	}

	if !spk && spklimit.Allow() {
		log.Println("Speaking")
		session.Speaking(context.Background(), voicegateway.Microphone)
		spk = true
	}

	var f32 []float32

	for _, sample := range samples {
		f32 = append(f32, float32(sample[0]))
		f32 = append(f32, float32(sample[1]))
	}

	n, err := encoder.EncodeFloat32(f32, buf)
	if err != nil {
		log.Println(err)
		return
	}

	pw.Write(buf[:n])
}

func IsSilent(in [][2]float64) bool {
	for _, v := range in {
		if v != Silence {
			return false
		}
	}
	return true
}