[Enhancement] Allow custom yt-dlp options (#176)

* Added option for yt-dlp config file usage

* renamed yt-dlp config file

* refactored to use a precedence-based approach

* Updated README

lib/pinchflat/boot/pre_job_startup_tasks.ex

@@ -32,7 +32,7 @@ defmodule Pinchflat.Boot.PreJobStartupTasks do
   @impl true
   def init(state) do
     reset_executing_jobs()
-    create_blank_cookie_file()
+    create_blank_yt_dlp_files()
     apply_default_settings()
 
     {:ok, state}
@@ -50,15 +50,19 @@ defmodule Pinchflat.Boot.PreJobStartupTasks do
     Logger.info("Reset #{count} executing jobs")
   end
 
-  defp create_blank_cookie_file do
+  defp create_blank_yt_dlp_files do
+    files = ["cookies.txt", "yt-dlp-configs/base-config.txt"]
     base_dir = Application.get_env(:pinchflat, :extras_directory)
-    filepath = Path.join(base_dir, "cookies.txt")
 
-    if !File.exists?(filepath) do
-      Logger.info("yt-dlp cookie file does not exist - creating it")
+    Enum.each(files, fn file ->
+      filepath = Path.join(base_dir, file)
 
-      FilesystemUtils.write_p!(filepath, "")
-    end
+      if !File.exists?(filepath) do
+        Logger.info("Creating blank file: #{filepath}")
+
+        FilesystemUtils.write_p!(filepath, "")
+      end
+    end)
   end
 
   defp apply_default_settings do

lib/pinchflat/downloading/download_option_builder.ex

@@ -10,8 +10,7 @@ defmodule Pinchflat.Downloading.DownloadOptionBuilder do
   @doc """
   Builds the options for yt-dlp to download media based on the given media's profile.
 
-  IDEA: consider adding the ability to pass in a second argument to override
-        these options
+  Returns {:ok, [Keyword.t()]}
   """
   def build(%MediaItem{} = media_item_with_preloads) do
     media_profile = media_item_with_preloads.source.media_profile
@@ -23,7 +22,8 @@ defmodule Pinchflat.Downloading.DownloadOptionBuilder do
         metadata_options(media_profile) ++
         quality_options(media_profile) ++
         sponsorblock_options(media_profile) ++
-        output_options(media_item_with_preloads)
+        output_options(media_item_with_preloads) ++
+        config_file_options(media_item_with_preloads)
 
     {:ok, built_options}
   end
@@ -128,6 +128,35 @@ defmodule Pinchflat.Downloading.DownloadOptionBuilder do
     end
   end
 
+  # This is put here instead of the CommandRunner module because it should only
+  # be applied to downloading - if it were in CommandRunner it would apply to
+  # all yt-dlp commands (like indexing)
+  defp config_file_options(media_item) do
+    base_dir = Path.join(Application.get_env(:pinchflat, :extras_directory), "yt-dlp-configs")
+    # Ordered by priority - the first file has the highest priority
+    filenames = [
+      "media-item-#{media_item.id}-config.txt",
+      "source-#{media_item.source_id}-config.txt",
+      "media-profile-#{media_item.source.media_profile_id}-config.txt",
+      "base-config.txt"
+    ]
+
+    config_filepaths =
+      Enum.reduce(filenames, [], fn filename, acc ->
+        filepath = Path.join(base_dir, filename)
+
+        case File.read(filepath) do
+          {:ok, file_data} ->
+            if String.trim(file_data) != "", do: [filepath | acc], else: acc
+
+          {:error, _} ->
+            acc
+        end
+      end)
+
+    Enum.map(config_filepaths, fn filepath -> {:config_locations, filepath} end)
+  end
+
   defp output_options(media_item_with_preloads) do
     [
       output: build_output_path_for(media_item_with_preloads.source)

lib/pinchflat/yt_dlp/command_runner.ex

@@ -27,13 +27,14 @@ defmodule Pinchflat.YtDlp.CommandRunner do
   def run(url, command_opts, output_template, addl_opts \\ []) do
     # This approach lets us mock the command for testing
     command = backend_executable()
-    # These must stay in exactly this order, hence why I'm giving it its own variable.
-    # Also, can't use RAM file since yt-dlp needs a concrete filepath.
+
     output_filepath = generate_output_filepath(addl_opts)
     print_to_file_opts = [{:print_to_file, output_template}, output_filepath]
-    cookie_opts = build_cookie_options()
-    formatted_command_opts = [url] ++ CliUtils.parse_options(command_opts ++ print_to_file_opts ++ cookie_opts)
+    external_file_opts = build_external_file_options()
+    # These must stay in exactly this order, hence why I'm giving it its own variable.
+    all_opts = command_opts ++ print_to_file_opts ++ external_file_opts
 
+    formatted_command_opts = [url] ++ CliUtils.parse_options(all_opts)
     Logger.info("[yt-dlp] called with: #{Enum.join(formatted_command_opts, " ")}")
 
     case System.cmd(command, formatted_command_opts, stderr_to_stdout: true) do
@@ -73,17 +74,25 @@ defmodule Pinchflat.YtDlp.CommandRunner do
     end
   end
 
-  defp build_cookie_options do
+  defp build_external_file_options do
     base_dir = Application.get_env(:pinchflat, :extras_directory)
-    cookie_file = Path.join(base_dir, "cookies.txt")
+    filename_options_map = %{cookies: "cookies.txt"}
 
-    case File.read(cookie_file) do
-      {:ok, cookie_data} ->
-        if String.trim(cookie_data) != "", do: [cookies: cookie_file], else: []
+    Enum.reduce(filename_options_map, [], fn {opt_name, filename}, acc ->
+      filepath = Path.join(base_dir, filename)
 
-      {:error, _} ->
-        []
-    end
+      case File.read(filepath) do
+        {:ok, file_data} ->
+          if String.trim(file_data) != "" do
+            [{opt_name, filepath} | acc]
+          else
+            acc
+          end
+
+        {:error, _} ->
+          acc
+      end
+    end)
   end
 
   defp backend_executable do