From 9641d01c0488b5bd3e15b697c40907284713bf30 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?F=C3=A1bio=20Souza?= <fabiobarboza7@hotmail.com>
Date: Sun, 28 Feb 2021 15:40:46 -0300
Subject: [PATCH] deposit flow

---
 lib/rocketpay.ex                              |  4 ++
 lib/rocketpay/accounts/deposit.ex             | 45 +++++++++++++++++++
 lib/rocketpay/users/create.ex                 | 16 ++++++-
 .../controllers/accounts_controller.ex        | 19 ++++++++
 lib/rocketpay_web/router.ex                   |  3 ++
 lib/rocketpay_web/views/users_view.ex         | 17 +++++--
 6 files changed, 100 insertions(+), 4 deletions(-)
 create mode 100644 lib/rocketpay/accounts/deposit.ex
 create mode 100644 lib/rocketpay_web/controllers/accounts_controller.ex

diff --git a/lib/rocketpay.ex b/lib/rocketpay.ex
index def6357..424b93c 100644
--- a/lib/rocketpay.ex
+++ b/lib/rocketpay.ex
@@ -1,5 +1,9 @@
 defmodule Rocketpay do
   alias Rocketpay.Users.Create, as: UserCreate
 
+  alias Rocketpay.Accouns.Deposit
+
   defdelegate create_user(params), to: UserCreate, as: :call
+
+  defdelegate deposit(params), to: Deposit, as: :call
 end
diff --git a/lib/rocketpay/accounts/deposit.ex b/lib/rocketpay/accounts/deposit.ex
new file mode 100644
index 0000000..b64ee3f
--- /dev/null
+++ b/lib/rocketpay/accounts/deposit.ex
@@ -0,0 +1,45 @@
+defmodule Rocketpay.Accounts.Deposit do
+  alias Ecto.Multi
+
+  alias Rocketpay.{Account, Repo}
+
+  def call(%{"id" => id, "value" => value}) do
+    Multi.new()
+      |> Multi.run(:account, fn repo, _changes -> get_account(repo, id) end)
+      |> Multi.run(:update_balance, fn repo, %{account: account} ->
+        update_balance(repo, account, value)
+      end)
+  end
+
+  defp get_account(repo, id) do
+    case repo.get(Account, id) do
+      nil -> {:error, "Account, not found!"}
+      account -> {:ok,  account}
+    end
+  end
+
+  defp update_balance(repo, account, value) do
+    account
+      |> sum_values(value)
+      |> update_account(repo)
+  end
+
+  defp sum_values(%Account{balance: balance}, value) do
+    value
+      |>Decimal.cast()
+      |> handle_cast(balance)
+  end
+
+  defp handle_cast({:ok, value}, balance), do: Decimal.add(value, balance)
+  defp handle_cast(:error, _balanace), do: {:error, "Invalid deposit value!"}
+
+  defp update_account({:error, _reason} = error, _repo), do: error
+
+  defp update_account(value, repo) do
+    params = %{balance: value}
+
+    params
+      |> Account.changeset()
+      |>  repo.update()
+  end
+end
diff --git a/lib/rocketpay/users/create.ex b/lib/rocketpay/users/create.ex
index 00f4764..58e99d7 100644
--- a/lib/rocketpay/users/create.ex
+++ b/lib/rocketpay/users/create.ex
@@ -1,5 +1,5 @@
 defmodule Rocketpay.Users.Create do
-  alias Rocketpay.{User, Account}
+  alias Rocketpay.{User, Repo,  Account}
   alias Ecto.Multi
 
   def call(params) do
@@ -8,6 +8,10 @@ defmodule Rocketpay.Users.Create do
       |> Multi.run(:create_account, fn repo, %{create_user: user} ->
         insert_account(repo, user)
       end)
+      |> Multi.run(:preload_data, fn repo, %{create_user: user} ->
+        preload_data(repo, user)
+      end)
+      |> run_transaction()
   end
 
   defp insert_account(repo, user) do
@@ -20,6 +24,16 @@ defmodule Rocketpay.Users.Create do
     params = %{user_id: user_id, balance: "0.00"}
 
     Account.changeset(params)
+  end
+
+  defp preload_data(repo, user) do
+    {:ok, repo.preload(user, :account)}
+  end
 
+  defp run_transaction(multi) do
+    case Repo.transaction(multi) do
+      {:error, _operation, reason, _changes} -> {:error, reason}
+      {:ok, %{preload_data: user}} -> {:ok, user}
+    end
   end
 end
diff --git a/lib/rocketpay_web/controllers/accounts_controller.ex b/lib/rocketpay_web/controllers/accounts_controller.ex
new file mode 100644
index 0000000..52797b9
--- /dev/null
+++ b/lib/rocketpay_web/controllers/accounts_controller.ex
@@ -0,0 +1,19 @@
+defmodule RocketpayWeb.AccountsController do
+  use RocketpayWeb, :controller
+
+  alias Rocketpay.Account
+
+  action_fallback RocketpayWeb.FallbackController
+
+  def deposit(conn, params) do
+    with {:ok, %Account{} = account} <- Rocketpay.deposit(params) do
+      conn
+      |> put_status(:ok)
+      |> render("update.json", account: account)
+    end
+  end
+
+  def withdraw(conn, params) do
+
+  end
+end
diff --git a/lib/rocketpay_web/router.ex b/lib/rocketpay_web/router.ex
index c71cdf6..bad8034 100644
--- a/lib/rocketpay_web/router.ex
+++ b/lib/rocketpay_web/router.ex
@@ -10,6 +10,9 @@ defmodule RocketpayWeb.Router do
 
     get "/:filename", WelcomeController, :index
     post "/users", UsersController, :create
+
+    post "/accounts/:id/deposit", AccountsController, :deposit
+    post "/accounts/:id/withdraw", AccountsController, :withdraw
   end
 
   # Enables LiveDashboard only for development
diff --git a/lib/rocketpay_web/views/users_view.ex b/lib/rocketpay_web/views/users_view.ex
index 95f6d87..33befd5 100644
--- a/lib/rocketpay_web/views/users_view.ex
+++ b/lib/rocketpay_web/views/users_view.ex
@@ -1,13 +1,24 @@
 defmodule RocketpayWeb.UsersView do
-  alias Rocketpay.User
+  alias Rocketpay.{Account, User}
 
-  def render("create.json", %{user: %User{id: id, name: name, nickname: nickname}}) do
+  def render("create.json", %{
+        user: %User{
+          account: %Account{id: account_id, balance: balance},
+          id: id,
+          name: name,
+          nickname: nickname
+        }
+      }) do
     %{
       message: "User created",
       user: %{
         id: id,
         name: name,
-        nickname: nickname
+        nickname: nickname,
+        account: %{
+          id: account_id,
+          balance: balance
+        }
       }
     }
   end