From 4cdf4c528a0d796b4d58d020d567f346ad05f5cc Mon Sep 17 00:00:00 2001
From: Anna Schumaker <Anna@NoWheyCreamery.com>
Date: Thu, 9 Dec 2021 17:22:25 -0500
Subject: [PATCH] audio: Implement our own about-to-finish handling

The playbin's about-to-finish signal triggers in a different thread,
which Gtk is very much not happy about, and often results in both the
about-to-finish and eos handlers getting called (and therefore multiple
tracks getting picked from the queue).

Fix this by checking how much time is left during the regular position
changed timeout function and triggering about-to-finish manually

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>
---
 audio/bass.py      | 16 +++++++---------
 audio/test_bass.py |  2 +-
 2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/audio/bass.py b/audio/bass.py
index 5d6e4e6..eec843e 100644
--- a/audio/bass.py
+++ b/audio/bass.py
@@ -11,6 +11,8 @@ Gst.init(sys.argv)
 
 from . import replaygain
 
+TIMEOUT = 100
+
 
 class BassPlayer(GObject.GObject):
     def __init__(self):
@@ -22,7 +24,6 @@ class BassPlayer(GObject.GObject):
         self.video  = Gst.ElementFactory.make("fakesink")
 
         self.playbin = Gst.ElementFactory.make("playbin")
-        self.playbin.connect("about-to-finish", self.__about_to_finish__)
         self.playbin.set_property("audio-sink", self.audio)
         self.playbin.set_property("video-sink", self.video)
         self.playbin.set_property("volume", lib.settings.get_float("audio.volume"))
@@ -38,9 +39,6 @@ class BassPlayer(GObject.GObject):
 
         self.timeout = None
 
-    def __about_to_finish__(self, playbin):
-        self.emit("about-to-finish")
-
     def __eos__(self, bus, message):
         self.emit("eos")
 
@@ -110,9 +108,6 @@ class BassPlayer(GObject.GObject):
         self.playbin.set_property("volume", vol)
         lib.settings.set("audio.volume", vol)
 
-    def about_to_finish(self, playbin):
-        pass
-
     def state_changed(self, bus, message):
         if message.src == self.playbin:
             (old, new, pending) = message.parse_state_changed()
@@ -152,7 +147,7 @@ class BassPlayer(GObject.GObject):
     @GObject.Signal
     def playback_start(self):
         if not self.timeout:
-            self.timeout = GLib.timeout_add(200, self.timeout_function)
+            self.timeout = GLib.timeout_add(TIMEOUT, self.timeout_function)
 
     @GObject.Signal
     def playback_paused(self):
@@ -162,4 +157,7 @@ class BassPlayer(GObject.GObject):
 
     @GObject.Signal
     def position_changed(self):
-        pass
+        remaining = self.duration - self.position
+        if remaining < 2 * Gst.SECOND:
+            if remaining + (TIMEOUT * Gst.MSECOND) >= 2 * Gst.SECOND:
+                self.emit("about-to-finish")
diff --git a/audio/test_bass.py b/audio/test_bass.py
index 74f69b1..328d3b9 100644
--- a/audio/test_bass.py
+++ b/audio/test_bass.py
@@ -32,7 +32,7 @@ class TestBassPlayer(unittest.TestCase):
         self.assertEqual(base.playbin.get_property("video-sink"), base.video)
         self.assertEqual(base.playbin.get_state(Gst.CLOCK_TIME_NONE)[1],
                          Gst.State.READY)
-        self.assertIsNone(base.timeout, 0)
+        self.assertIsNone(base.timeout)
 
     def test_bass_player_bus(self):
         base = bass.BassPlayer()