[Enhancement] Allow setting preference for video/audio codec (#255)

* [WIP] started on codec parser

* Added codec preferences to settings model

* [WIP] added basic codec preference fields to settings form

* Hooked up the backend portion of the codec preference work

* Added codec settings to frontend

* Ensured you can remove codec data

lib/pinchflat/downloading/codec_parser.ex

@@ -0,0 +1,82 @@
+defmodule Pinchflat.Downloading.CodecParser do
+  @moduledoc """
+  Functions for generating yt-dlp codec strings
+  """
+
+  alias Pinchflat.Settings
+
+  @doc """
+  Generate a video codec string based on the value of the video_codec_preference setting.
+
+  Returns binary()
+  """
+  def generate_vcodec_string_from_settings do
+    generate_vcodec_string(Settings.get!(:video_codec_preference))
+  end
+
+  @doc """
+  Generate an audio codec string based on the value of the audio_codec_preference setting.
+
+  Returns binary()
+  """
+  def generate_acodec_string_from_settings do
+    generate_acodec_string(Settings.get!(:audio_codec_preference))
+  end
+
+  @doc """
+  Generate a video codec string from a list of video codecs.
+
+  If the list is nil or empty, the default video codec is AVC.
+
+  Returns binary()
+  """
+  def generate_vcodec_string(nil), do: "bestvideo[vcodec~='^avc']/bestvideo"
+  def generate_vcodec_string([]), do: generate_vcodec_string(nil)
+
+  def generate_vcodec_string(video_codecs) do
+    video_codecs
+    |> Enum.map(&video_codec_map()[&1])
+    |> Enum.reject(&is_nil/1)
+    |> Enum.map(&"bestvideo[vcodec~='^#{&1}']")
+    |> Enum.concat(["bestvideo"])
+    |> Enum.join("/")
+  end
+
+  @doc """
+  Generate an audio codec string from a list of audio codecs.
+
+  If the list is nil or empty, the default audio codec is MP4A.
+
+  Returns binary()
+  """
+  def generate_acodec_string(nil), do: "bestaudio[acodec~='^mp4a']/bestaudio"
+  def generate_acodec_string([]), do: generate_acodec_string(nil)
+
+  def generate_acodec_string(audio_codecs) do
+    audio_codecs
+    |> Enum.map(&audio_codec_map()[&1])
+    |> Enum.reject(&is_nil/1)
+    |> Enum.map(&"bestaudio[acodec~='^#{&1}']")
+    |> Enum.concat(["bestaudio"])
+    |> Enum.join("/")
+  end
+
+  @doc false
+  def video_codec_map do
+    %{
+      "av01" => "av01",
+      "avc" => "avc",
+      "vp9" => "vp0?9"
+    }
+  end
+
+  @doc false
+  def audio_codec_map do
+    %{
+      "aac" => "aac",
+      "mp4a" => "mp4a",
+      "mp3" => "mp3",
+      "opus" => "opus"
+    }
+  end
+end

lib/pinchflat/downloading/download_option_builder.ex

@@ -6,6 +6,7 @@ defmodule Pinchflat.Downloading.DownloadOptionBuilder do
   alias Pinchflat.Sources
   alias Pinchflat.Sources.Source
   alias Pinchflat.Media.MediaItem
+  alias Pinchflat.Downloading.CodecParser
   alias Pinchflat.Downloading.OutputPathBuilder
 
   alias Pinchflat.Utils.FilesystemUtils, as: FSUtils
@@ -121,28 +122,26 @@ defmodule Pinchflat.Downloading.DownloadOptionBuilder do
   end
 
   defp quality_options(media_profile) do
-    video_codec_option = fn res ->
-      [format_sort: "res:#{res},+codec:avc:m4a", remux_video: "mp4"]
-    end
-
-    audio_format_precedence = [
-      "bestaudio[ext=m4a]",
-      "bestaudio[ext=mp3]",
-      "bestaudio",
-      "best[ext=m4a]",
-      "best[ext=mp3]",
-      "best"
-    ]
+    vcodec_string = CodecParser.generate_vcodec_string_from_settings()
+    acodec_string = CodecParser.generate_acodec_string_from_settings()
 
     case media_profile.preferred_resolution do
       # Also be aware that :audio disabled all embedding options for subtitles
-      :audio -> [:extract_audio, format: Enum.join(audio_format_precedence, "/")]
-      :"360p" -> video_codec_option.("360")
-      :"480p" -> video_codec_option.("480")
-      :"720p" -> video_codec_option.("720")
-      :"1080p" -> video_codec_option.("1080")
-      :"2160p" -> video_codec_option.("2160")
-      :"4320p" -> video_codec_option.("4320")
+      :audio ->
+        [:extract_audio, format: "#{acodec_string}/best"]
+
+      resolution_atom ->
+        {resolution_string, _} =
+          resolution_atom
+          |> Atom.to_string()
+          |> Integer.parse()
+
+        [
+          format_sort: "res:#{resolution_string}",
+          # Since Plex doesn't support reading metadata from MKV
+          remux_video: "mp4",
+          format: "((#{vcodec_string})+(#{acodec_string}))/best"
+        ]
     end
   end
 

lib/pinchflat/settings/setting.ex

@@ -11,7 +11,14 @@ defmodule Pinchflat.Settings.Setting do
     :pro_enabled,
     :yt_dlp_version,
     :apprise_version,
-    :apprise_server
+    :apprise_server,
+    :video_codec_preference,
+    :audio_codec_preference
+  ]
+
+  @virtual_fields [
+    :video_codec_preference_string,
+    :audio_codec_preference_string
   ]
 
   @required_fields ~w(
@@ -25,12 +32,43 @@ defmodule Pinchflat.Settings.Setting do
     field :yt_dlp_version, :string
     field :apprise_version, :string
     field :apprise_server, :string
+
+    field :video_codec_preference, {:array, :string}, default: []
+    field :audio_codec_preference, {:array, :string}, default: []
+    field :video_codec_preference_string, :string, default: nil, virtual: true
+    field :audio_codec_preference_string, :string, default: nil, virtual: true
   end
 
   @doc false
   def changeset(setting, attrs) do
     setting
     |> cast(attrs, @allowed_fields)
+    |> cast(attrs, @virtual_fields, empty_values: [])
+    |> convert_codec_preference_strings()
     |> validate_required(@required_fields)
   end
+
+  defp convert_codec_preference_strings(changeset) do
+    fields = [
+      video_codec_preference_string: :video_codec_preference,
+      audio_codec_preference_string: :audio_codec_preference
+    ]
+
+    Enum.reduce(fields, changeset, fn {virtual_field, actual_field}, changeset ->
+      case get_change(changeset, virtual_field) do
+        nil ->
+          changeset
+
+        value ->
+          new_value =
+            value
+            |> String.split(">")
+            |> Enum.map(&String.trim/1)
+            |> Enum.reject(&(String.trim(&1) == ""))
+            |> Enum.map(&String.downcase/1)
+
+          put_change(changeset, actual_field, new_value)
+      end
+    end)
+  end
 end