[Enhancement] Media from before a source's cutoff date is now automatically deleted (#329)

* Changed the purpose of the 'culled_at' flag. renamed some methods

* implemented new culling behaviour for source cutoff dates

* Removed culled_at flag if a media item gets redownloaded

* Updated source form

* Removed unused method

test/pinchflat/downloading/media_downloader_test.exs

@@ -5,6 +5,7 @@ defmodule Pinchflat.Downloading.MediaDownloaderTest do
   import Pinchflat.SourcesFixtures
   import Pinchflat.ProfilesFixtures
 
+  alias Pinchflat.Media
   alias Pinchflat.Downloading.MediaDownloader
 
   setup do
@@ -123,6 +124,12 @@ defmodule Pinchflat.Downloading.MediaDownloaderTest do
       assert DateTime.diff(DateTime.utc_now(), updated_media_item.media_downloaded_at) < 2
     end
 
+    test "it sets the culled_at to nil", %{media_item: media_item} do
+      Media.update_media_item(media_item, %{culled_at: DateTime.utc_now()})
+      assert {:ok, updated_media_item} = MediaDownloader.download_for_media_item(media_item)
+      assert updated_media_item.culled_at == nil
+    end
+
     test "it extracts the title", %{media_item: media_item} do
       assert {:ok, updated_media_item} = MediaDownloader.download_for_media_item(media_item)
       assert updated_media_item.title == "Pinchflat Example Video"