udia

###############################################################################
# The contents of this file are subject to the Common Public Attribution
# License Version 1.0. (the "License"); you may not use this file except in
# compliance with the License. You may obtain a copy of the License at
# https://raw.githubusercontent.com/udia-software/udia/master/LICENSE.
# The License is based on the Mozilla Public License Version 1.1, but
# Sections 14 and 15 have been added to cover use of software over a computer
# network and provide for limited attribution for the Original Developer.
# In addition, Exhibit A has been modified to be consistent with Exhibit B.
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
# the specific language governing rights and limitations under the License.
#
# The Original Code is UDIA.
#
# The Original Developer is the Initial Developer.  The Initial Developer of
# the Original Code is Udia Software Incorporated.
#
# All portions of the code written by UDIA are Copyright (c) 2016-2017
# Udia Software Incorporated. All Rights Reserved.
###############################################################################
defmodule Udia.Web.Auth do
  import Plug.Conn
  import Comeonin.Bcrypt, only: [checkpw: 2, dummy_checkpw: 0]
  import Phoenix.Controller
  alias Udia.Web.Router.Helpers

  def init(opts) do
    Keyword.fetch!(opts, :repo)
  end

  def call(conn, repo) do
    user_id = get_session(conn, :user_id)

    cond do
      user = conn.assigns[:current_user] ->
        put_current_user(conn, user)
      user = user_id && repo.get(Udia.User, user_id) ->
        put_current_user(conn, user)
      true ->
        assign(conn, :current_user, nil)
    end
  end

  def login(conn, user) do
    conn
    |> put_current_user(user)
    |> put_session(:user_id, user.id)
    |> configure_session(renew: true)
  end

  defp put_current_user(conn, user) do
    token = Phoenix.Token.sign(conn, "user socket", user.id)

    conn
    |> assign(:current_user, user)
    |> assign(:user_token, token)
  end

  def login_by_username_and_pass(conn, username, given_pass, opts) do
    repo = Keyword.fetch!(opts, :repo)
    user = repo.get_by(Udia.User, username: username)

    cond do
      user && checkpw(given_pass, user.password_hash) ->
        {:ok, login(conn, user)}
      user ->
        {:error, :unauthorized, conn}
      true ->
        dummy_checkpw()
        {:error, :not_found, conn}
    end
  end

  def logout(conn) do
    configure_session(conn, drop: true)
  end

  def authenticate_user(conn, _opts) do
    if conn.assigns.current_user do
      conn
    else
      conn
      |> put_flash(:error, "You must be logged in to access that page")
      |> redirect(to: Helpers.node_path(conn, :index))
      |> halt()
    end
  end
end