defmodule CoreUtils.ViewHelper do
  @moduledoc """
  Presentation helpers
  """

  alias CoreUtils.StructUtil

  def translate_errors(%{causes: causes}) do
    %{status: :error, code: 1, message: "Validation errors", causes: causes}
  end

  def translate_errors(changeset) do
    %{
      status: :error,
      code: 1,
      message: "Validation errors",
      causes: Ecto.Changeset.traverse_errors(changeset, &:erlang.element(1, &1))
    }
  end

  defimpl Poison.Encoder, for: Tuple do
    def encode(tuple, _options) do
      tuple
      |> Tuple.to_list()
      |> Poison.encode!()
    end
  end

  def encode(%{__struct__: Core.Models.Task} = struct, options \\ []) do
    struct =
      if struct.geom do
        {lon, lat} = struct.geom.coordinates
        %{struct | lon: lon, lat: lat}
      else
        struct
      end

    enconde_model(struct, options)
  end

  def encode(struct, options) do
    enconde_model(struct, options)
  end

  defp enconde_model(model, options) do
    model
    |> StructUtil.nested_parse()
    |> sanitize_map()
    |> Poison.Encoder.Map.encode(options)
  end

  defp sanitize_map(map) do
    map
    |> Enum.filter(fn
      {_, %Ecto.Association.NotLoaded{}} -> false
      {:__meta__, _} -> false
      {:__struct__, _} -> false
      {_, _} -> true
    end)
    |> Map.new()
  end

end