neiam /gitgud

defmodule GitGud.Accounts.UserNotifier do
  import Swoosh.Email

  alias GitGud.Mailer
  alias GitGud.Accounts.User

  # Delivers the email using the application mailer.
  defp deliver(recipient, subject, body) do
    email =
      new()
      |> to(recipient)
      |> from(sender())
      |> subject(subject)
      |> text_body(body)

    with {:ok, _metadata} <- Mailer.deliver(email) do
      {:ok, email}
    end
  end

  defp sender do
    cfg = Application.get_env(:git_gud, Mailer, [])
    name = Keyword.get(cfg, :from_name, "GitGud")
    addr = Keyword.get(cfg, :from_address, "noreply@example.com")
    {name, addr}
  end

  @doc """
  Deliver instructions to update a user email.
  """
  def deliver_update_email_instructions(user, url) do
    deliver(user.email, "Update email instructions", """

    ==============================

    Hi #{user.email},

    You can change your email by visiting the URL below:

    #{url}

    If you didn't request this change, please ignore this.

    ==============================
    """)
  end

  @doc """
  Deliver instructions to log in with a magic link.
  """
  def deliver_login_instructions(user, url) do
    case user do
      %User{confirmed_at: nil} -> deliver_confirmation_instructions(user, url)
      _ -> deliver_magic_link_instructions(user, url)
    end
  end

  defp deliver_magic_link_instructions(user, url) do
    deliver(user.email, "Log in instructions", """

    ==============================

    Hi #{user.email},

    You can log into your account by visiting the URL below:

    #{url}

    If you didn't request this email, please ignore this.

    ==============================
    """)
  end

  defp deliver_confirmation_instructions(user, url) do
    deliver(user.email, "Confirmation instructions", """

    ==============================

    Hi #{user.email},

    You can confirm your account by visiting the URL below:

    #{url}

    If you didn't create an account with us, please ignore this.

    ==============================
    """)
  end
end