Boutique Inventory - Elixir - Exercism

boutique_inventory.ex

defmodule BoutiqueInventory do
  def sort_by_price(inventory) do
    inventory
    |> Enum.sort_by(&(&1.price))
  end

  def with_missing_price(inventory) do
    inventory
    |> Enum.filter(&is_nil(&1.price))
  end

  def update_names(inventory, old_word, new_word) do
    inventory
    |> Enum.map(&replace_word(&1, old_word, new_word))
  end

  defp replace_word(map, old_word, new_word) do
    name = String.replace(map.name, old_word, new_word)
    Map.put(map, :name, name)
  end

  def increase_quantity(item, count) do
    qbs = Map.new(item.quantity_by_size, fn {k, v} -> {k, v + count} end)
    %{item | quantity_by_size: qbs }
  end

  def total_quantity(item) do
    item.quantity_by_size
    |> Enum.reduce(0, fn {_, v}, sum -> sum + v end)
  end
end