From 29eade9b4a79f23637597af88cdee9b8e2e44eea Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Tue, 4 May 2021 18:49:34 +0900
Subject: [PATCH] audio/internal/readdriver: Bug fix: Implement Suspend/Resume
 for browsers

Closes #1630
---
 audio/audio.go                           |  6 ++++++
 audio/internal/readerdriver/driver.go    |  2 ++
 audio/internal/readerdriver/driver_js.go | 16 ++++++++++++++++
 audio/readerplayer.go                    | 14 ++++++++++++++
 4 files changed, 38 insertions(+)

diff --git a/audio/audio.go b/audio/audio.go
index 62bb75bf8..2fd5c60ed 100644
--- a/audio/audio.go
+++ b/audio/audio.go
@@ -127,9 +127,15 @@ func NewContext(sampleRate int) *Context {
 	h := getHook()
 	h.OnSuspendAudio(func() {
 		c.semaphore <- struct{}{}
+		if s, ok := np.(interface{ suspend() }); ok {
+			s.suspend()
+		}
 	})
 	h.OnResumeAudio(func() {
 		<-c.semaphore
+		if s, ok := np.(interface{ resume() }); ok {
+			s.resume()
+		}
 	})
 
 	h.AppendHookOnBeforeUpdate(func() error {
diff --git a/audio/internal/readerdriver/driver.go b/audio/internal/readerdriver/driver.go
index e0d2198c4..e29509832 100644
--- a/audio/internal/readerdriver/driver.go
+++ b/audio/internal/readerdriver/driver.go
@@ -21,6 +21,8 @@ import (
 type Context interface {
 	NewPlayer(io.Reader) Player
 	MaxBufferSize() int
+	Suspend()
+	Resume()
 	io.Closer
 }
 
diff --git a/audio/internal/readerdriver/driver_js.go b/audio/internal/readerdriver/driver_js.go
index 94d468ef7..7af48e1ef 100644
--- a/audio/internal/readerdriver/driver_js.go
+++ b/audio/internal/readerdriver/driver_js.go
@@ -139,6 +139,14 @@ func (c *context) MaxBufferSize() int {
 	return c.oneBufferSize() * 2
 }
 
+func (c *context) Suspend() {
+	c.audioContext.Call("suspend")
+}
+
+func (c *context) Resume() {
+	c.audioContext.Call("resume")
+}
+
 func (p *player) Pause() {
 	if p.state != playerPlay {
 		return
@@ -299,6 +307,14 @@ func (w *go2cppDriverWrapper) MaxBufferSize() int {
 	return w.c.MaxBufferSize()
 }
 
+func (w *go2cppDriverWrapper) Suspend() {
+	// Do nothing so far.
+}
+
+func (w *go2cppDriverWrapper) Resume() {
+	// Do nothing so far.
+}
+
 func (w *go2cppDriverWrapper) Close() error {
 	return w.c.Close()
 }
diff --git a/audio/readerplayer.go b/audio/readerplayer.go
index 8ba91ace0..da21d98fe 100644
--- a/audio/readerplayer.go
+++ b/audio/readerplayer.go
@@ -60,6 +60,20 @@ func (f *readerPlayerFactory) newPlayerImpl(context *Context, src io.Reader) (pl
 	return p, nil
 }
 
+func (f *readerPlayerFactory) suspend() {
+	if f.context == nil {
+		return
+	}
+	f.context.Suspend()
+}
+
+func (f *readerPlayerFactory) resume() {
+	if f.context == nil {
+		return
+	}
+	f.context.Resume()
+}
+
 func (p *readerPlayer) ensurePlayer() error {
 	// Initialize the underlying player lazily to enable calling NewContext in an 'init' function.
 	// Accessing the underlying player functions requires the environment to be already initialized,