Extract Tailwind release helpers

lib/mix/tasks/tailwind/release.ex

@@ -0,0 +1,27 @@
+defmodule Mix.Tasks.Tailwind.Release do
+  @latest_version_url "https://api.github.com/repos/tailwindlabs/tailwindcss/releases/latest"
+
+  def fetch_latest_version! do
+    Application.ensure_all_started(:req)
+
+    Req.get!(@latest_version_url).body["tag_name"]
+    |> String.replace_prefix("v", "")
+  end
+
+  def fetch_current_version do
+    Application.get_env(:tailwind, :version)
+  end
+
+  def update_config_file!(config_file, current_version, latest_version) do
+    config_contents = File.read!(config_file)
+
+    new_config_contents =
+      String.replace(
+        config_contents,
+        ~s(version: "#{current_version}"),
+        "version: \"#{latest_version}\""
+      )
+
+    File.write!(config_file, new_config_contents)
+  end
+end