defmodule Soroban.Types.UInt256 do
  @moduledoc """
  `UInt256` struct definition.
  """

  @behaviour Soroban.Types.Spec

  alias Stellar.TxBuild.SCVal

  defstruct [:value]

  @type value :: non_neg_integer()
  @type t :: %__MODULE__{value: value()}

  @impl true
  def new(value) when is_integer(value), do: %__MODULE__{value: value}
  def new(_value), do: {:error, :invalid}

  @impl true
  def to_sc_val(%__MODULE__{value: value}) do
    <<hi_hi::size(64), hi_lo::size(64), lo_hi::size(64), lo_lo::size(64)>> = <<value::size(256)>>
    SCVal.new(u256: %{hi_hi: hi_hi, hi_lo: hi_lo, lo_hi: lo_hi, lo_lo: lo_lo})
  end

  def to_sc_val(_error), do: {:error, :invalid_struct_uint256}
end