dotfiles/backend/lib/prymn/servers.ex

defmodule Prymn.Servers do
  @moduledoc """
  The Servers context.
  """

  import Ecto.Query, warn: false
  alias Prymn.Repo

  alias Prymn.Servers.Server

  @doc """
  Returns the list of servers.

  ## Examples

      iex> list_servers()
      [%Server{}, ...]

  """
  def list_servers do
    Repo.all(Server)
  end

  @doc """
  Gets a single server.

  Raises `Ecto.NoResultsError` if the Server does not exist.

  ## Examples

      iex> get_server!(123)
      %Server{}

      iex> get_server!(456)
      ** (Ecto.NoResultsError)

  """
  def get_server!(id), do: Repo.get!(Server, id)

  @doc """

  Start a new server connection with the app.
  """
  def create_server(attrs \\ %{}) do
    # Create a unique registration token
    %Server{registration_token: :crypto.strong_rand_bytes(16)}
    |> Server.changeset(attrs)
    |> Repo.insert()
  end

  @doc """
  Registers a server using a registration token.
  """
  def register_server(token, public_ip) do
    # TODO: Validate public ip

    case Base.decode64(token) do
      {:ok, token} ->
        from(s in Server, where: s.registration_token == ^token, select: s)
        |> Repo.one()
        |> update_server(%{public_ip: public_ip})

      :error ->
        {:error, "token is not a valid base64 encoded string"}
    end
  end

  @doc """
  Updates a server.

  ## Examples

      iex> update_server(server, %{field: new_value})
      {:ok, %Server{}}

      iex> update_server(server, %{field: bad_value})
      {:error, %Ecto.Changeset{}}

  """
  def update_server(%Server{} = server, attrs) do
    server
    |> Server.changeset(attrs)
    |> Repo.update()
  end

  @doc """
  Deletes a server.

  ## Examples

      iex> delete_server(server)
      {:ok, %Server{}}

      iex> delete_server(server)
      {:error, %Ecto.Changeset{}}

  """
  def delete_server(%Server{} = server) do
    Repo.delete(server)
  end

  @doc """
  Returns an `%Ecto.Changeset{}` for tracking server changes.

  ## Examples

      iex> change_server(server)
      %Ecto.Changeset{data: %Server{}}

  """
  def change_server(%Server{} = server, attrs \\ %{}) do
    Server.changeset(server, attrs)
  end
end