Fix a bug occuring when audio track is linked after video tracks in muxed_av mode (#114)

* Fix a bug with using audio pad ref instead of buffered video pad ref

* Add test checking different order of linking

Author: varsill

README.md

@@ -13,7 +13,7 @@ In future, the support for MPEG-DASH is planned as well
 Add the following line to your `deps` in `mix.exs`. Run `mix deps.get`.
 
 ```elixir
-	{:membrane_http_adaptive_stream_plugin, "~> 0.18.7"}
+	{:membrane_http_adaptive_stream_plugin, "~> 0.18.8"}
 ```
 
 ## Usage Example

lib/membrane_http_adaptive_stream/sink_bin.ex

@@ -192,7 +192,7 @@ defmodule Membrane.HTTPAdaptiveStream.SinkBin do
       bin_input(pad)
       |> child({:parser, ref}, get_parser(pad_options.encoding, state))
       |> child({:cmaf_muxer, ref}, cmaf_child_definiton(pad_options))
-      |> via_in(pad, options: track_options(ctx))
+      |> via_in(pad, options: track_options(ctx.pad_options))
       |> get_child(:sink)
 
     state = increment_streams_counters(state)
@@ -214,7 +214,7 @@ defmodule Membrane.HTTPAdaptiveStream.SinkBin do
       bin_input(pad)
       |> child({:parser, ref}, parser)
       |> child({:cmaf_muxer, ref}, muxer)
-      |> via_in(pad, options: track_options(ctx))
+      |> via_in(pad, options: track_options(ctx.pad_options))
       |> get_child(:sink),
       get_child(:audio_tee)
       |> get_child({:cmaf_muxer, ref})
@@ -245,7 +245,7 @@ defmodule Membrane.HTTPAdaptiveStream.SinkBin do
           bin_input(pad_data.ref)
           |> child({:parser, cmaf_ref}, get_parser(pad_data.options.encoding, state))
           |> child({:cmaf_muxer, cmaf_ref}, muxer)
-          |> via_in(pad, options: track_options(ctx))
+          |> via_in(pad_data.ref, options: track_options(pad_data.options))
           |> get_child(:sink),
           get_child(:audio_tee)
           |> get_child({:cmaf_muxer, cmaf_ref})
@@ -338,8 +338,8 @@ defmodule Membrane.HTTPAdaptiveStream.SinkBin do
     {[notify_parent: {:track_playable, track_info}], state}
   end
 
-  defp track_options(context) do
-    context.pad_options
+  defp track_options(pad_options) do
+    pad_options
     |> Map.take([:track_name, :segment_duration, :partial_segment_duration, :max_framerate])
     |> Keyword.new()
   end

mix.exs

@@ -1,7 +1,7 @@
 defmodule Membrane.HTTPAdaptiveStream.MixProject do
   use Mix.Project
 
-  @version "0.18.7"
+  @version "0.18.8"
   @github_url "https://github.com/membraneframework/membrane_http_adaptive_stream_plugin"
 
   def project do

test/membrane_http_adaptive_stream/integration_test/fixtures/muxed_av_reordered/index.m3u8

@@ -0,0 +1,9 @@
+#EXTM3U
+#EXT-X-VERSION:7
+#EXT-X-INDEPENDENT-SEGMENTS
+#EXT-X-STREAM-INF:BANDWIDTH=1252874,AVERAGE-BANDWIDTH=917273,RESOLUTION=480x270,FRAME-RATE=25,CODECS="avc1.42e015,mp4a.40.2"
+video_480x270.m3u8
+#EXT-X-STREAM-INF:BANDWIDTH=763588,AVERAGE-BANDWIDTH=447929,RESOLUTION=540x360,FRAME-RATE=25,CODECS="avc1.640015,mp4a.40.2"
+video_540x360.m3u8
+#EXT-X-STREAM-INF:BANDWIDTH=1087782,AVERAGE-BANDWIDTH=597835,RESOLUTION=720x480,FRAME-RATE=25,CODECS="avc1.64001e,mp4a.40.2"
+video_720x480.m3u8