Update ex_doc, add llms.txt support (#55)

* Update ex_doc, add llms.txt support, update description

* Set ex_doc dependency to >= 0.40.0

* Rename prepend_llms_links to append_llms_links

Author: FelonEkonom

README.md

@@ -27,7 +27,7 @@ sudo apt-get install libmad0-dev
 Then, add the following line to your `deps` in `mix.exs`:
 
 ```elixir
-	{:membrane_audio_mix_plugin, "~> 0.16.4"}
+	{:membrane_audio_mix_plugin, "~> 0.16.5"}
 ```
 
 and run `mix deps.get`.

mix.exs

@@ -1,7 +1,7 @@
 defmodule Membrane.AudioMix.Mixfile do
   use Mix.Project
 
-  @version "0.16.4"
+  @version "0.16.5"
   @github_url "https://github.com/membraneframework/membrane_audio_mix_plugin"
 
   def project do
@@ -23,7 +23,8 @@ defmodule Membrane.AudioMix.Mixfile do
       name: "Membrane Audio Mix plugin",
       source_url: @github_url,
       homepage_url: "https://membraneframework.org",
-      docs: docs()
+      docs: docs(),
+      aliases: [docs: ["docs", &append_llms_links/1]]
     ]
   end
 
@@ -43,7 +44,7 @@ defmodule Membrane.AudioMix.Mixfile do
       {:membrane_raw_audio_format, "~> 0.12.0"},
       {:unifex, "~> 1.0"},
       {:bunch, "~> 1.3"},
-      {:ex_doc, ">= 0.0.0", only: :dev, runtime: false},
+      {:ex_doc, ">= 0.40.0", only: :dev, runtime: false},
       {:dialyxir, ">= 0.0.0", only: :dev, runtime: false},
       {:credo, ">= 0.0.0", only: :dev, runtime: false},
       {:membrane_file_plugin, "~> 0.16.0", only: :test},
@@ -82,7 +83,6 @@ defmodule Membrane.AudioMix.Mixfile do
     [
       main: "readme",
       extras: ["README.md", "LICENSE"],
-      formatters: ["html"],
       source_ref: "v#{@version}",
       nest_modules_by_prefix: [
         Membrane.AudioMixer,
@@ -99,4 +99,26 @@ defmodule Membrane.AudioMix.Mixfile do
       ]
     ]
   end
+
+  defp append_llms_links(_args) do
+    output_dir = docs()[:output] || "doc"
+    path = Path.join(output_dir, "llms.txt")
+
+    if File.exists?(path) do
+      existing = File.read!(path)
+
+      footer = """
+
+
+      ## See Also
+
+      - [Membrane Framework AI Skill](https://hexdocs.pm/membrane_core/skill.md)
+      - [Membrane Core](https://hexdocs.pm/membrane_core/llms.txt)
+      """
+
+      File.write!(path, String.trim_trailing(existing) <> footer)
+    else
+      IO.warn("#{path} not found — llms.txt was not generated, check your ex_doc configuration")
+    end
+  end
 end