audio: Refactoring

audio/audio.go

@@ -48,6 +48,10 @@ const (
 	bytesPerSample = 2 * channelNum
 )
 
+type newPlayerImpler interface {
+	newPlayerImpl(context *Context, src io.Reader) (playerImpl, error)
+}
+
 // A Context represents a current state of audio.
 //
 // At most one Context object can exist in one process.
@@ -55,7 +59,7 @@ const (
 //
 // For a typical usage example, see examples/wav/main.go.
 type Context struct {
-	wc writerContext
+	np newPlayerImpler
 
 	// inited represents whether the audio device is initialized and available or not.
 	// On Android, audio loop cannot be started unless JVM is accessible. After updating one frame, JVM should exist.
@@ -97,7 +101,7 @@ func NewContext(sampleRate int) *Context {
 
 	c := &Context{
 		sampleRate: sampleRate,
-		wc:         newWriterContext(sampleRate),
+		np:         newWriterContext(sampleRate),
 		players:    map[playerImpl]struct{}{},
 		inited:     make(chan struct{}),
 		semaphore:  make(chan struct{}, 1),
@@ -268,7 +272,7 @@ type playerImpl interface {
 // A Player doesn't close src even if src implements io.Closer.
 // Closing the source is src owner's responsibility.
 func NewPlayer(context *Context, src io.Reader) (*Player, error) {
-	pi, err := newWriterContextPlayerImpl(context, context.wc, src)
+	pi, err := context.np.newPlayerImpl(context, src)
 	if err != nil {
 		return nil, err
 	}

audio/export_test.go

@@ -19,15 +19,15 @@ import (
 )
 
 type (
-	dummyContext struct{}
+	dummyDriver struct{}
 	dummyPlayer struct{}
 )
 
-func (d *dummyContext) NewPlayer() io.WriteCloser {
+func (d *dummyDriver) NewPlayer() io.WriteCloser {
 	return &dummyPlayer{}
 }
 
-func (d *dummyContext) Close() error {
+func (d *dummyDriver) Close() error {
 	return nil
 }
 
@@ -40,7 +40,7 @@ func (p *dummyPlayer) Close() error {
 }
 
 func init() {
-	writerContextForTesting = &dummyContext{}
+	writerDriverForTesting = &dummyDriver{}
 }
 
 type dummyHook struct {

audio/otodriver.go

@@ -21,14 +21,14 @@ import (
 	"github.com/hajimehoshi/oto"
 )
 
-func newOtoContext(sampleRate int, initCh chan struct{}) *otoContext {
+func newOtoDriver(sampleRate int, initCh chan struct{}) *otoDriver {
-	return &otoContext{
+	return &otoDriver{
 		sampleRate: sampleRate,
 		initCh:     initCh,
 	}
 }
 
-type otoContext struct {
+type otoDriver struct {
 	sampleRate int
 	initCh     <-chan struct{}
 
@@ -36,18 +36,18 @@ type otoContext struct {
 	once sync.Once
 }
 
-func (c *otoContext) NewPlayer() io.WriteCloser {
+func (c *otoDriver) NewPlayer() io.WriteCloser {
 	return &otoPlayer{c: c}
 }
 
-func (c *otoContext) Close() error {
+func (c *otoDriver) Close() error {
 	if c.c == nil {
 		return nil
 	}
 	return c.c.Close()
 }
 
-func (c *otoContext) ensureContext() error {
+func (c *otoDriver) ensureContext() error {
 	var err error
 	c.once.Do(func() {
 		<-c.initCh
@@ -57,7 +57,7 @@ func (c *otoContext) ensureContext() error {
 }
 
 type otoPlayer struct {
-	c    *otoContext
+	c    *otoDriver
 	p    *oto.Player
 	once sync.Once
 }

audio/writercontext.go

@@ -23,18 +23,18 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/hooks"
 )
 
-// writerContext represents a context represented as io.WriteClosers.
+// writerDriver represents a driver using io.WriteClosers.
-// The actual implementation is oto.Context.
+// The actual implementation is otoDriver.
-type writerContext interface {
+type writerDriver interface {
 	NewPlayer() io.WriteCloser
 	io.Closer
 }
 
-var writerContextForTesting writerContext
+var writerDriverForTesting writerDriver
 
-func newWriterContext(sampleRate int) writerContext {
+func newWriterDriver(sampleRate int) writerDriver {
-	if writerContextForTesting != nil {
+	if writerDriverForTesting != nil {
-		return writerContextForTesting
+		return writerDriverForTesting
 	}
 
 	ch := make(chan struct{})
@@ -45,12 +45,22 @@ func newWriterContext(sampleRate int) writerContext {
 		})
 		return nil
 	})
-	return newOtoContext(sampleRate, ch)
+	return newOtoDriver(sampleRate, ch)
+}
+
+type writerContext struct {
+	driver writerDriver
+}
+
+func newWriterContext(sampleRate int) *writerContext {
+	return &writerContext{
+		driver: newWriterDriver(sampleRate),
+	}
 }
 
 type writerContextPlayerImpl struct {
 	context          *Context
-	writerContext    writerContext
+	driver           writerDriver
 	src              io.Reader
 	playing          bool
 	closedExplicitly bool
@@ -64,10 +74,10 @@ type writerContextPlayerImpl struct {
 	m sync.Mutex
 }
 
-func newWriterContextPlayerImpl(context *Context, writerContext writerContext, src io.Reader) (*writerContextPlayerImpl, error) {
+func (c *writerContext) newPlayerImpl(context *Context, src io.Reader) (playerImpl, error) {
 	p := &writerContextPlayerImpl{
 		context: context,
-		writerContext: writerContext,
+		driver:  c.driver,
 		src:     src,
 		volume:  1,
 	}
@@ -119,7 +129,7 @@ func (p *writerContextPlayerImpl) Play() {
 func (p *writerContextPlayerImpl) loop() {
 	p.context.waitUntilInited()
 
-	w := p.writerContext.NewPlayer()
+	w := p.driver.NewPlayer()
 	wclosed := make(chan struct{})
 	defer func() {
 		<-wclosed