+
+ def all_between_user_sets(
+ source_users,
+ target_users
+ )
+ when is_list(source_users) and is_list(target_users) do
+ source_user_ids = User.binary_id(source_users)
+ target_user_ids = User.binary_id(target_users)
+
+ __MODULE__
+ |> where(
+ fragment(
+ "(follower_id = ANY(?) AND following_id = ANY(?)) OR \
+ (follower_id = ANY(?) AND following_id = ANY(?))",
+ ^source_user_ids,
+ ^target_user_ids,
+ ^target_user_ids,
+ ^source_user_ids
+ )
+ )
+ |> Repo.all()
+ end
+
+ def find(following_relationships, follower, following) do
+ Enum.find(following_relationships, fn
+ fr -> fr.follower_id == follower.id and fr.following_id == following.id
+ end)
+ end
+
+ defp validate_not_self_relationship(%Changeset{} = changeset) do
+ changeset
+ |> validate_follower_id_following_id_inequality()
+ |> validate_following_id_follower_id_inequality()
+ end
+
+ defp validate_follower_id_following_id_inequality(%Changeset{} = changeset) do
+ validate_change(changeset, :follower_id, fn _, follower_id ->
+ if follower_id == get_field(changeset, :following_id) do
+ [source_id: "can't be equal to following_id"]
+ else
+ []
+ end
+ end)
+ end
+
+ defp validate_following_id_follower_id_inequality(%Changeset{} = changeset) do
+ validate_change(changeset, :following_id, fn _, following_id ->
+ if following_id == get_field(changeset, :follower_id) do
+ [target_id: "can't be equal to follower_id"]
+ else
+ []
+ end
+ end)
+ end