From c7a9a93937d102f257992570dc30da57250a066a Mon Sep 17 00:00:00 2001
From: casey <casey@GREENPOINT>
Date: Fri, 17 Jun 2016 22:17:55 -0700
Subject: [PATCH] Optimized prefetch of next track to happen way ahead of time
 to limit chance of gapless playback not working properly.

---
 src/core/audio/GaplessTransport.cpp          |  5 ++---
 src/musikbox/app/service/PlaybackService.cpp | 21 +++++++++++---------
 src/musikbox/app/service/PlaybackService.h   |  1 +
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/core/audio/GaplessTransport.cpp b/src/core/audio/GaplessTransport.cpp
index 6c87ce93f..b7013b7c8 100644
--- a/src/core/audio/GaplessTransport.cpp
+++ b/src/core/audio/GaplessTransport.cpp
@@ -297,7 +297,6 @@ void GaplessTransport::OnPlaybackStarted(Player* player) {
 
 void GaplessTransport::OnPlaybackAlmostEnded(Player* player) {
     this->SetNextCanStart(true);
-    this->RaiseStreamEvent(GaplessTransport::StreamAlmostDone, player);
 
     {
         boost::recursive_mutex::scoped_lock lock(this->stateMutex);
@@ -308,10 +307,11 @@ void GaplessTransport::OnPlaybackAlmostEnded(Player* player) {
             this->StartWithPlayer(this->nextPlayer);
         }
     }
+
+    this->RaiseStreamEvent(GaplessTransport::StreamAlmostDone, player);
 }
 
 void GaplessTransport::OnPlaybackFinished(Player* player) {
-    this->SetNextCanStart(true);
     this->RaiseStreamEvent(GaplessTransport::StreamFinished, player);
 
     bool stopped = false;
@@ -345,7 +345,6 @@ void GaplessTransport::OnPlaybackFinished(Player* player) {
 }
 
 void GaplessTransport::OnPlaybackError(Player* player) {
-    this->SetNextCanStart(true);
     this->RaiseStreamEvent(GaplessTransport::StreamError, player);
     this->SetPlaybackState(GaplessTransport::PlaybackStopped);
     DEFER(&GaplessTransport::RemoveActive, player);
diff --git a/src/musikbox/app/service/PlaybackService.cpp b/src/musikbox/app/service/PlaybackService.cpp
index c19277384..f2cdbfb36 100755
--- a/src/musikbox/app/service/PlaybackService.cpp
+++ b/src/musikbox/app/service/PlaybackService.cpp
@@ -67,19 +67,20 @@ PlaybackService::PlaybackService(LibraryPtr library, ITransport& transport)
     this->nextIndex = NO_POSITION;
 }
 
+void PlaybackService::PrepareNextTrack() {
+    if (this->playlist.Count() > this->index + 1) {
+        if (this->nextIndex != this->index + 1) {
+            this->nextIndex = this->index + 1;
+            this->transport.PrepareNextTrack(URI_AT_INDEX(nextIndex));
+        }
+    }
+}
+
 void PlaybackService::ProcessMessage(IMessage &message) {
     if (message.Type() == MESSAGE_STREAM_EVENT) {
         int64 eventType = message.UserData1();
 
-        if (eventType == ITransport::StreamAlmostDone) {
-            if (this->playlist.Count() > this->index + 1) {
-                if (this->nextIndex != this->index + 1) {
-                    this->nextIndex = this->index + 1;
-                    this->transport.PrepareNextTrack(URI_AT_INDEX(nextIndex));
-                }
-            }
-        }
-        else if (eventType == ITransport::StreamPlaying) {
+        if (eventType == ITransport::StreamPlaying) {
             if (this->nextIndex != NO_POSITION) {
                 this->index = this->nextIndex;
                 this->nextIndex = NO_POSITION;
@@ -88,6 +89,8 @@ void PlaybackService::ProcessMessage(IMessage &message) {
             if (this->index != NO_POSITION) {
                 this->TrackChanged(this->index, this->playlist.Get(this->index));
             }
+
+            this->PrepareNextTrack();
         }
     }
     else if (message.Type() == MESSAGE_PLAYBACK_EVENT) {
diff --git a/src/musikbox/app/service/PlaybackService.h b/src/musikbox/app/service/PlaybackService.h
index 01f2ce8d6..9af685536 100755
--- a/src/musikbox/app/service/PlaybackService.h
+++ b/src/musikbox/app/service/PlaybackService.h
@@ -77,6 +77,7 @@ namespace musik {
             private:
                 void OnStreamEvent(int eventType, std::string uri);
                 void OnPlaybackEvent(int eventType);
+                void PrepareNextTrack();
 
                 musik::core::LibraryPtr library;
                 musik::core::audio::ITransport& transport;