Weight-based random sampling

Questions & Help Questions
1

I’m new to Elixir, and relatively new to functional programming. I’ve just written this little algorithm to take a weighted sample from a list of tuples;

# items = [apples: 10, oranges: 30, bananas: 60]
defp weight_based_choice(items) do
    max = sum_weights(items)

    state = %{
      current: 0,
      choice: nil,
      random_value: Enum.random(1..max)
    }

    Enum.reduce(items, state, fn item, state ->
      weight = elem(item, 1)
      state = %{state | current: state[:current] + weight}

      choice =
        if(state[:random_value] <= state[:current]) do
          elem(item, 0)
        else
          nil
        end

      if state[:choice] == nil && choice != nil do
        %{state | choice: choice}
      else
        state
      end
    end)[:choice]
  end

  defp sum_weights(items) do
    Enum.reduce(items, 0, fn item, acc ->
      weight = elem(item, 1)
      acc + weight
    end)
  end

Are there more idiomatic ways to do this?