chess/web/controllers/game_controller.ex

defmodule Chess.GameController do
  use Chess.Web, :controller

  alias Chess.Game

  def index(conn, _params) do
    changeset = Game.changeset(%Game{})
    games = Repo.all(Game)
    render(conn, "index.html", games: games, changeset: changeset)
  end

  def new(conn, _params) do
    changeset = Game.changeset(%Game{})
    render(conn, "new.html", changeset: changeset)
  end

  def create(conn, _params) do
    changeset = Game.changeset(%Game{})

    case Repo.insert(changeset) do
      {:ok, _game} ->
        conn
        |> put_flash(:info, "Game created successfully.")
        |> redirect(to: game_path(conn, :index))
      {:error, changeset} ->
        render(conn, "new.html", changeset: changeset)
    end
  end

  def show(conn, %{"id" => id}) do
    game = Repo.get!(Game, id)
    render(conn, "show.html", game: game)
  end

  def edit(conn, %{"id" => id}) do
    game = Repo.get!(Game, id)
    changeset = Game.changeset(game)
    render(conn, "edit.html", game: game, changeset: changeset)
  end

  def update(conn, %{"id" => id, "game" => game_params}) do
    game = Repo.get!(Game, id)
    changeset = Game.changeset(game, game_params)

    case Repo.update(changeset) do
      {:ok, game} ->
        conn
        |> put_flash(:info, "Game updated successfully.")
        |> redirect(to: game_path(conn, :show, game))
      {:error, changeset} ->
        render(conn, "edit.html", game: game, changeset: changeset)
    end
  end

  def delete(conn, %{"id" => id}) do
    game = Repo.get!(Game, id)

    # Here we use delete! (with a bang) because we expect
    # it to always work (and if it does not, it will raise).
    Repo.delete!(game)

    conn
    |> put_flash(:info, "Game deleted successfully.")
    |> redirect(to: game_path(conn, :index))
  end
end