Refactor params parsing out of live views

Closes #125

lib/music_library_web/live/collection_live/index.ex

@@ -226,7 +226,7 @@ defmodule MusicLibraryWeb.CollectionLive.Index do
 
   defp apply_action(socket, :index, params) do
     query = params["query"] || ""
-    order = parse_order(params["order"] || "purchase")
+    order = parse_order(params["order"] || "purchase", [:purchase, :alphabetical, :release])
     total_records = Collection.search_records_count(query)
 
     record_list_params =
@@ -293,9 +293,6 @@ defmodule MusicLibraryWeb.CollectionLive.Index do
      |> load_and_assign_records(socket.assigns.record_list_params)}
   end
 
-  defp parse_mode("grid"), do: :grid
-  defp parse_mode("list"), do: :list
-
   defp load_and_assign_records(socket, record_list_params) do
     offset = page_to_offset(record_list_params.page, record_list_params.page_size)
 
@@ -315,10 +312,6 @@ defmodule MusicLibraryWeb.CollectionLive.Index do
     |> stream(:records, records, reset: true)
   end
 
-  defp parse_order("alphabetical"), do: :alphabetical
-  defp parse_order("purchase"), do: :purchase
-  defp parse_order("release"), do: :release
-
   defp order_path(record_list_params, order) do
     qs =
       record_list_params

lib/music_library_web/live/wishlist_live/index.ex

@@ -196,7 +196,7 @@ defmodule MusicLibraryWeb.WishlistLive.Index do
 
   defp apply_action(socket, :index, params) do
     query = params["query"] || ""
-    order = parse_order(params["order"] || "insertion")
+    order = parse_order(params["order"] || "insertion", [:insertion, :alphabetical, :release])
     total_records = Wishlist.search_records_count(query)
 
     record_list_params =
@@ -278,9 +278,6 @@ defmodule MusicLibraryWeb.WishlistLive.Index do
      |> load_and_assign_records(socket.assigns.record_list_params)}
   end
 
-  defp parse_mode("grid"), do: :grid
-  defp parse_mode("list"), do: :list
-
   defp load_and_assign_records(socket, record_list_params) do
     offset = page_to_offset(record_list_params.page, record_list_params.page_size)
 
@@ -298,10 +295,6 @@ defmodule MusicLibraryWeb.WishlistLive.Index do
     |> stream(:records, records, reset: true)
   end
 
-  defp parse_order("alphabetical"), do: :alphabetical
-  defp parse_order("insertion"), do: :insertion
-  defp parse_order("release"), do: :release
-
   defp order_path(record_list_params, order) do
     qs =
       record_list_params

lib/music_library_web/live_helpers/params.ex

@@ -55,6 +55,17 @@ defmodule MusicLibraryWeb.LiveHelpers.Params do
     Map.put(params, :order, order)
   end
 
+  @spec parse_mode(String.t()) :: :grid | :list
+  def parse_mode("grid"), do: :grid
+  def parse_mode("list"), do: :list
+
+  @spec parse_order(String.t(), [atom(), ...]) :: atom()
+  def parse_order(order, [_ | _] = allowed) when is_binary(order) do
+    Enum.find(allowed, hd(allowed), fn a -> Atom.to_string(a) == order end)
+  end
+
+  def parse_order(_, []), do: raise(ArgumentError, "allowed orders must not be empty")
+
   @spec apply_fallback_index(Phoenix.LiveView.Socket.t(), map(), atom(), function()) ::
           Phoenix.LiveView.Socket.t()
   def apply_fallback_index(socket, params, stream_key, apply_action_fn) do