defmodule LiveChart.BaseChart do
  @moduledoc """
  Base camp for all of your LiveChart needs.
  """
  alias __MODULE__

  defstruct [:title, :colors, :dataset]

  @typep color_name() :: atom()

  @type t() :: %__MODULE__{
          title: String.t(),
          colors: %{color_name() => String.t() | Gradient.t()},
          dataset: LiveChart.dataset()
        }

  defimpl LiveChart.Chart, for: __MODULE__ do
    alias LiveChart.{BaseChart, Gradient}
    def title(%BaseChart{title: nil}), do: ""
    def title(%BaseChart{title: title}), do: title

    def colors(%BaseChart{colors: nil}), do: {}
    def colors(%BaseChart{colors: colors}), do: colors

    def gradient_colors(%BaseChart{colors: nil}), do: %{}

    def gradient_colors(%BaseChart{colors: colors}) do
      colors
      |> Enum.filter(fn {_key, value} ->
        case value do
          %Gradient{} -> true
          _ -> false
        end
      end)
      |> Map.new()
    end
  end
end