boutique-inventory

elixir/boutique-inventory/lib/boutique_inventory.ex

@@ -0,0 +1,41 @@
+defmodule BoutiqueInventory do
+  def sort_by_price(inventory) do
+    Enum.sort_by(inventory, & &1[:price])
+  end
+
+  def with_missing_price(inventory) do
+    Enum.filter(inventory, &(!&1[:price]))
+  end
+
+  def update_names(inventory, old_word, new_word) do
+    inventory
+    |> Enum.map(fn item ->
+      new_name = String.replace(item.name, old_word, new_word)
+      %{item | name: new_name}
+    end)
+  end
+
+  def increase_quantity(item, count) do
+    item
+    |> Map.get_and_update(:quantity_by_size, fn quantities ->
+      {quantities, update_quantities(quantities, count)}
+    end)
+    |> elem(1)
+  end
+
+  defp update_quantities(quantities, count) do
+    quantities
+    |> Map.to_list()
+    |> Enum.map(&increase_size_quantity(&1, count))
+    |> Enum.into(%{})
+  end
+
+  defp increase_size_quantity({key, value}, count), do: {key, value + count}
+
+  def total_quantity(item) do
+    item.quantity_by_size
+    |> Enum.reduce(0, &sum_total_quantity/2)
+  end
+
+  defp sum_total_quantity({_key, value}, acc), do: acc + value
+end