beer song elixir solution

elixir/beer-song/lib/beer_song.ex

@@ -0,0 +1,47 @@
+defmodule BeerSong do
+  @basic "~s bottle~s of beer on the wall, ~s bottle~s of beer.\n~s, ~s bottle~s of beer on the wall.~n"
+  @take "Take ~s down and pass it around"
+  @store "Go to the store and buy some more"
+
+  @doc """
+  Get a single verse of the beer song
+  """
+  @spec verse(integer) :: String.t()
+  def verse(number) do
+    :io_lib.format(@basic, get_args(number)) |> to_string()
+  end
+
+  @doc """
+  Get the entire beer song for a given range of numbers of bottles.
+  """
+  @spec lyrics(Range.t()) :: String.t()
+  def lyrics(), do: lyrics(99..0)
+
+  def lyrics(range) do
+    range |> Enum.map(&verse(&1)) |> Enum.join("\n")
+  end
+
+  defp get_args(number) do
+    cond do
+      number == 0 ->
+        ["No more", "s", "no more", "s", @store, "99", "s"]
+
+      number == 1 ->
+        ["1", "", "1", "", :io_lib.format(@take, ["it"]) |> to_string(), "no more", "s"]
+
+      number == 2 ->
+        ["2", "s", "2", "s", :io_lib.format(@take, ["one"]) |> to_string(), "1", ""]
+
+      true ->
+        [
+          "#{number}",
+          "s",
+          "#{number}",
+          "s",
+          :io_lib.format(@take, ["one"]) |> to_string(),
+          "#{number - 1}",
+          "s"
+        ]
+    end
+  end
+end