Extract LastFm module

lib/last_fm.ex

@@ -0,0 +1,43 @@
+defmodule LastFm do
+  def get_artist_info(musicbrainz_id, name) do
+    last_fm_config = last_fm_config()
+
+    case last_fm_config.api.get_artist_info(
+           {:musicbrainz_id, musicbrainz_id},
+           last_fm_config
+         ) do
+      {:ok, info} ->
+        {:ok, info}
+
+      {:error, :invalid_parameters} ->
+        # Sometimes the artist info cannot be identified with the MusicBrainz ID,
+        # because Last.fm doesn't have that information. In that case, we try again with the artist name.
+        last_fm_config.api.get_artist_info({:name, name}, last_fm_config)
+
+      error ->
+        error
+    end
+  end
+
+  def get_similar_artists(musicbrainz_id, name) do
+    last_fm_config = last_fm_config()
+
+    case last_fm_config.api.get_similar_artists(
+           {:musicbrainz_id, musicbrainz_id},
+           last_fm_config
+         ) do
+      {:ok, info} ->
+        {:ok, info}
+
+      {:error, :invalid_parameters} ->
+        # Sometimes the artist info cannot be identified with the MusicBrainz ID,
+        # because Last.fm doesn't have that information. In that case, we try again with the artist name.
+        last_fm_config.api.get_similar_artists({:name, name}, last_fm_config)
+
+      error ->
+        error
+    end
+  end
+
+  defp last_fm_config, do: LastFm.Config.resolve(:music_library)
+end