add tracking saved to db

lib/pokemon_couture/accounts/user.ex

@@ -8,7 +8,7 @@ defmodule PokemonCouture.Accounts.User do
     field :password, :string, virtual: true
     field :hashed_password, :string
     field :confirmed_at, :naive_datetime
-    many_to_many :clothes, PokemonCouture.Shops.Clothes, join_through: "ownerships", unique: :true
+    many_to_many :clothes, PokemonCouture.Shops.Clothes, join_through: "ownerships", unique: :true, on_replace: :delete
 
     timestamps()
   end

lib/pokemon_couture/shops.ex

@@ -21,6 +21,9 @@ defmodule PokemonCouture.Shops do
     Repo.all(Clothes)
   end
 
+  def list_clothes_with_owners do
+    Repo.all(from c in Clothes, preload: [:users])
+  end
   @doc """
   Gets a single clothes.
 
@@ -101,4 +104,18 @@ defmodule PokemonCouture.Shops do
   def change_clothes(%Clothes{} = clothes, attrs \\ %{}) do
     Clothes.changeset(clothes, attrs)
   end
+
+  def add_owner(clothes, user) do
+    clothes
+    |> Ecto.Changeset.change()
+    |> Ecto.Changeset.put_assoc(:users, [user | clothes.users])
+    |> Repo.update!()
+  end
+
+  def remove_owner(clothes, user) do
+    clothes
+    |> Ecto.Changeset.change()
+    |> Ecto.Changeset.put_assoc(:users, List.delete(clothes.users, user))
+    |> Repo.update!()
+  end
 end

lib/pokemon_couture/shops/clothes.ex

@@ -8,7 +8,7 @@ defmodule PokemonCouture.Shops.Clothes do
     field :game, :string
     field :location, :string
 
-    many_to_many :users, PokemonCouture.Accounts.User, join_through: "ownerships", unique: :true
+    many_to_many :users, PokemonCouture.Accounts.User, join_through: "ownerships", unique: :true, on_replace: :delete
 
     timestamps()
   end