From 95a7ef2ab2c645b0f2d45fa07aada58eb87d1671 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gabriel=20Pr=C3=A1?= <gabrielpra1@gmail.com>
Date: Mon, 9 Sep 2019 19:27:07 -0300
Subject: [PATCH] Support delete with changeset (#59)

---
 .gitignore                |  1 +
 lib/paper_trail.ex        | 21 ++++++++++-----
 test/paper_trail_test.exs | 55 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 70 insertions(+), 7 deletions(-)

diff --git a/.gitignore b/.gitignore
index 755b6055..dcc1bebe 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@
 /deps
 erl_crash.dump
 *.ez
+.elixir_ls
diff --git a/lib/paper_trail.ex b/lib/paper_trail.ex
index 1a0a6fb6..d862dae7 100644
--- a/lib/paper_trail.ex
+++ b/lib/paper_trail.ex
@@ -278,7 +278,7 @@ defmodule PaperTrail do
 
     %Version{
       event: "insert",
-      item_type: model.__struct__ |> Module.split() |> List.last(),
+      item_type: get_item_type(model),
       item_id: get_model_id(model),
       item_changes: serialize(model),
       originator_id:
@@ -298,8 +298,8 @@ defmodule PaperTrail do
 
     %Version{
       event: "update",
-      item_type: changeset.data.__struct__ |> Module.split() |> List.last(),
-      item_id: get_model_id(changeset.data),
+      item_type: get_item_type(changeset),
+      item_id: get_model_id(changeset),
       item_changes: changeset.changes,
       originator_id:
         case originator_ref do
@@ -312,15 +312,15 @@ defmodule PaperTrail do
     |> add_prefix(options[:prefix])
   end
 
-  defp make_version_struct(%{event: "delete"}, model, options) do
+  defp make_version_struct(%{event: "delete"}, model_or_changeset, options) do
     originator = PaperTrail.RepoClient.originator()
     originator_ref = options[originator[:name]] || options[:originator]
 
     %Version{
       event: "delete",
-      item_type: model.__struct__ |> Module.split() |> List.last(),
-      item_id: get_model_id(model),
-      item_changes: serialize(model),
+      item_type: get_item_type(model_or_changeset),
+      item_id: get_model_id(model_or_changeset),
+      item_changes: serialize(model_or_changeset),
       originator_id:
         case originator_ref do
           nil -> nil
@@ -348,6 +348,8 @@ defmodule PaperTrail do
     |> List.first()
   end
 
+  defp serialize(%Ecto.Changeset{data: data}), do: serialize(data)
+
   defp serialize(model) do
     relationships = model.__struct__.__schema__(:associations)
     Map.drop(model, [:__struct__, :__meta__] ++ relationships)
@@ -356,6 +358,11 @@ defmodule PaperTrail do
   defp add_prefix(changeset, nil), do: changeset
   defp add_prefix(changeset, prefix), do: Ecto.put_meta(changeset, prefix: prefix)
 
+  defp get_item_type(%Ecto.Changeset{data: data}), do: get_item_type(data)
+  defp get_item_type(model), do: model.__struct__ |> Module.split() |> List.last()
+
+  def get_model_id(%Ecto.Changeset{data: data}), do: get_model_id(data)
+
   def get_model_id(model) do
     {_, model_id} = List.first(Ecto.primary_key(model))
 
diff --git a/test/paper_trail_test.exs b/test/paper_trail_test.exs
index 1200ac21..4480f3be 100644
--- a/test/paper_trail_test.exs
+++ b/test/paper_trail_test.exs
@@ -262,6 +262,61 @@ defmodule PaperTrailTest do
     assert company == company_before_deletion
   end
 
+  test "delete works with a changeset" do
+    user = create_user()
+    {:ok, insert_result} = create_company_with_version()
+    {:ok, update_result} = update_company_with_version(insert_result[:model])
+    company_before_deletion = first(Company, :id) |> @repo.one
+
+    changeset = Company.changeset(company_before_deletion, %{})
+    {:ok, result} = PaperTrail.delete(changeset, originator: user)
+
+    company_count = Company.count()
+    version_count = Version.count()
+
+    company = result[:model] |> serialize
+    version = result[:version] |> serialize
+
+    assert Map.keys(result) == [:model, :version]
+    assert company_count == 0
+    assert version_count == 3
+
+    assert Map.drop(company, [:id, :inserted_at, :updated_at]) == %{
+             name: "Acme LLC",
+             is_active: true,
+             city: "Hong Kong",
+             website: "http://www.acme.com",
+             address: nil,
+             facebook: "acme.llc",
+             twitter: nil,
+             founded_in: nil
+           }
+
+    assert Map.drop(version, [:id, :inserted_at]) == %{
+             event: "delete",
+             item_type: "SimpleCompany",
+             item_id: company.id,
+             item_changes: %{
+               id: company.id,
+               inserted_at: company.inserted_at,
+               updated_at: company.updated_at,
+               name: "Acme LLC",
+               is_active: true,
+               website: "http://www.acme.com",
+               city: "Hong Kong",
+               address: nil,
+               facebook: "acme.llc",
+               twitter: nil,
+               founded_in: nil
+             },
+             originator_id: user.id,
+             origin: nil,
+             meta: nil
+           }
+
+    assert company == serialize(company_before_deletion)
+  end
+
   test "PaperTrail.delete/2 with an error returns and error tuple like Repo.delete/2" do
     {:ok, insert_company_result} = create_company_with_version()