defmodule Plotex.TimeUnitsTest do
  use ExUnit.Case
  doctest Plotex
  require Logger
  alias Plotex.ViewRange

  @config %Plotex.Axis.Units.Time{}

  test "a first b after" do
    dt_a = DateTime.from_iso8601("2019-05-20T05:00:00.836Z") |> elem(1)
    dt_b = DateTime.from_iso8601("2019-05-20T05:05:00.836Z") |> elem(1)

    %{basis_name: unit_name, val: unit_val, order: _unit_ord, diff: delta} =
      Plotex.Axis.Units.Time.units_for(dt_a, dt_b, %{ @config | ticks: 3})

    assert delta == 300
    assert unit_name == :minute
    assert unit_val == 60
  end

  test "a after b first" do
    dt_a = DateTime.from_iso8601("2019-05-20T05:05:00.836Z") |> elem(1)
    dt_b = DateTime.from_iso8601("2019-05-20T05:00:00.836Z") |> elem(1)

    %{basis_name: unit_name, val: unit_val, order: _unit_ord, diff: delta} =
        Plotex.Axis.Units.Time.units_for(dt_a, dt_b, %{ @config | ticks: 3})
    assert delta == 300
    assert unit_name == :minute
    assert unit_val == 60
  end

  test "time scale" do
    dt_a = DateTime.from_iso8601("2019-05-20T05:04:10.836Z") |> elem(1)
    dt_b = DateTime.from_iso8601("2019-05-20T05:15:00.836Z") |> elem(1)

    scale = Plotex.Axis.Units.scale(@config, %ViewRange{start: dt_a, stop: dt_b})

    scale! = scale[:data] |> Enum.take(30)

    # for i <- scale! do Logger.warn("#{inspect(i)}") end

    assert length(scale!) == 12
  end

  test "time scale with 4 ticks " do
    dt_a = DateTime.from_iso8601("2019-05-20T05:04:10.836Z") |> elem(1)
    dt_b = DateTime.from_iso8601("2019-05-20T05:15:00.836Z") |> elem(1)

    scale = Plotex.Axis.Units.scale(%{ @config | ticks: 4}, %ViewRange{start: dt_a, stop: dt_b})
    scale! = scale[:data] |> Enum.take(30)

    # for i <- scale! do Logger.warn("#{inspect(i)}") end

    assert length(scale!) == 4
  end

  test "hour time scale" do
    dt_a = ~U[2019-05-20T05:04:10.836Z]
    dt_b = ~U[2019-05-20T08:15:00.836Z]

    scale = Plotex.Axis.Units.scale(@config, %ViewRange{start: dt_a, stop: dt_b})

    scale! = scale[:data] |> Enum.take(30)

    # for i <- scale! do
      # Logger.warn("#{inspect(i)}")
    # end

    assert length(scale!) == 14
  end
end