refactor: extract minimal shared logic between HTML and EPUB formatters (#2147)

Signed-off-by: Yordis Prieto <yordis.prieto@gmail.com>

Author: yordis

lib/ex_doc/formatter.ex

@@ -0,0 +1,363 @@
+defmodule ExDoc.Formatter do
+  @moduledoc false
+
+  alias ExDoc.{Markdown, GroupMatcher, Utils}
+
+  @doc """
+  Autolinks and renders all docs.
+  """
+  def render_all(project_nodes, filtered_modules, ext, config, opts) do
+    base = [
+      apps: config.apps,
+      deps: config.deps,
+      ext: ext,
+      extras: extra_paths(config),
+      skip_undefined_reference_warnings_on: config.skip_undefined_reference_warnings_on,
+      skip_code_autolink_to: config.skip_code_autolink_to,
+      filtered_modules: filtered_modules
+    ]
+
+    project_nodes
+    |> Task.async_stream(
+      fn node ->
+        language = node.language
+
+        autolink_opts =
+          [
+            current_module: node.module,
+            file: node.moduledoc_file,
+            line: node.moduledoc_line,
+            module_id: node.id,
+            language: language
+          ] ++ base
+
+        docs_groups =
+          for group <- node.docs_groups do
+            docs =
+              for child_node <- group.docs do
+                id = id(node, child_node)
+
+                autolink_opts =
+                  autolink_opts ++
+                    [
+                      id: id,
+                      line: child_node.doc_line,
+                      file: child_node.doc_file,
+                      current_kfa: {child_node.type, child_node.name, child_node.arity}
+                    ]
+
+                specs = Enum.map(child_node.specs, &language.autolink_spec(&1, autolink_opts))
+                child_node = %{child_node | specs: specs}
+                render_doc(child_node, language, autolink_opts, opts)
+              end
+
+            %{render_doc(group, language, autolink_opts, opts) | docs: docs}
+          end
+
+        %{
+          render_doc(node, language, [{:id, node.id} | autolink_opts], opts)
+          | docs_groups: docs_groups
+        }
+      end,
+      timeout: :infinity
+    )
+    |> Enum.map(&elem(&1, 1))
+  end
+
+  @doc """
+  Builds extra nodes by normalizing the config entries.
+  """
+  def build_extras(config, ext) do
+    groups = config.groups_for_extras
+
+    language =
+      case config.proglang do
+        :erlang -> ExDoc.Language.Erlang
+        _ -> ExDoc.Language.Elixir
+      end
+
+    source_url_pattern = config.source_url_pattern
+
+    autolink_opts = [
+      apps: config.apps,
+      deps: config.deps,
+      ext: ext,
+      extras: extra_paths(config),
+      language: language,
+      skip_undefined_reference_warnings_on: config.skip_undefined_reference_warnings_on,
+      skip_code_autolink_to: config.skip_code_autolink_to
+    ]
+
+    extras =
+      config.extras
+      |> Enum.map(&normalize_extras/1)
+      |> Task.async_stream(
+        &build_extra(&1, groups, language, autolink_opts, source_url_pattern),
+        timeout: :infinity
+      )
+      |> Enum.map(&elem(&1, 1))
+
+    ids_count = Enum.reduce(extras, %{}, &Map.update(&2, &1.id, 1, fn c -> c + 1 end))
+
+    extras
+    |> Enum.map_reduce(1, fn extra, idx ->
+      if ids_count[extra.id] > 1, do: {disambiguate_id(extra, idx), idx + 1}, else: {extra, idx}
+    end)
+    |> elem(0)
+    |> Enum.sort_by(fn extra -> GroupMatcher.index(groups, extra.group) end)
+  end
+
+  def filter_list(:module, nodes) do
+    Enum.filter(nodes, &(&1.type != :task))
+  end
+
+  def filter_list(type, nodes) do
+    Enum.filter(nodes, &(&1.type == type))
+  end
+
+  # Helper functions
+
+  defp render_doc(%{doc: nil} = node, _language, _autolink_opts, _opts),
+    do: node
+
+  defp render_doc(%{doc: doc} = node, language, autolink_opts, opts) do
+    doc = autolink_and_highlight(doc, language, autolink_opts, opts)
+    %{node | doc: doc}
+  end
+
+  defp id(%{id: mod_id}, %{id: "c:" <> id}) do
+    "c:" <> mod_id <> "." <> id
+  end
+
+  defp id(%{id: mod_id}, %{id: "t:" <> id}) do
+    "t:" <> mod_id <> "." <> id
+  end
+
+  defp id(%{id: mod_id}, %{id: id}) do
+    mod_id <> "." <> id
+  end
+
+  defp autolink_and_highlight(doc, language, autolink_opts, opts) do
+    doc
+    |> language.autolink_doc(autolink_opts)
+    |> ExDoc.DocAST.highlight(language, opts)
+  end
+
+  defp extra_paths(config) do
+    Enum.reduce(config.extras, %{}, fn
+      path, acc when is_binary(path) ->
+        base = Path.basename(path)
+        Map.put(acc, base, Utils.text_to_id(Path.rootname(base)))
+
+      {path, opts}, acc ->
+        if Keyword.has_key?(opts, :url) do
+          acc
+        else
+          base = path |> to_string() |> Path.basename()
+
+          name =
+            Keyword.get_lazy(opts, :filename, fn -> Utils.text_to_id(Path.rootname(base)) end)
+
+          Map.put(acc, base, name)
+        end
+    end)
+  end
+
+  defp normalize_extras(base) when is_binary(base), do: {base, %{}}
+  defp normalize_extras({base, opts}), do: {base, Map.new(opts)}
+
+  defp disambiguate_id(extra, discriminator) do
+    Map.put(extra, :id, "#{extra.id}-#{discriminator}")
+  end
+
+  defp build_extra({input, %{url: _} = input_options}, groups, _lang, _auto, _url_pattern) do
+    input = to_string(input)
+    title = input_options[:title] || input
+    group = GroupMatcher.match_extra(groups, input_options[:url])
+
+    %{group: group, id: Utils.text_to_id(title), title: title, url: input_options[:url]}
+  end
+
+  defp build_extra({input, input_options}, groups, language, autolink_opts, source_url_pattern) do
+    input = to_string(input)
+    id = input_options[:filename] || input |> filename_to_title() |> Utils.text_to_id()
+    source_file = input_options[:source] || input
+    opts = [file: source_file, line: 1]
+
+    {extension, source, ast} =
+      case extension_name(input) do
+        extension when extension in ["", ".txt"] ->
+          source = File.read!(input)
+          ast = [{:pre, [], ["\n" <> source], %{}}]
+          {extension, source, ast}
+
+        extension when extension in [".md", ".livemd", ".cheatmd"] ->
+          source = File.read!(input)
+
+          ast =
+            source
+            |> Markdown.to_ast(opts)
+            |> ExDoc.DocAST.add_ids_to_headers([:h2, :h3])
+            |> autolink_and_highlight(language, [file: input] ++ autolink_opts, opts)
+
+          {extension, source, ast}
+
+        _ ->
+          raise ArgumentError,
+                "file extension not recognized, allowed extension is either .cheatmd, .livemd, .md, .txt or no extension"
+      end
+
+    {title_doc, title_text, ast} =
+      case ExDoc.DocAST.extract_title(ast) do
+        {:ok, title_doc, ast} -> {title_doc, ExDoc.DocAST.text(title_doc), ast}
+        :error -> {nil, nil, ast}
+      end
+
+    title = input_options[:title] || title_text || filename_to_title(input)
+    group = GroupMatcher.match_extra(groups, input)
+    source_path = source_file |> Path.relative_to(File.cwd!()) |> String.replace_leading("./", "")
+    source_url = source_url_pattern.(source_path, 1)
+    search_data = normalize_search_data!(input_options[:search_data])
+
+    %{
+      type: extra_type(extension),
+      source: source,
+      group: group,
+      id: id,
+      doc: ast,
+      source_path: source_path,
+      source_url: source_url,
+      search_data: search_data,
+      title: title,
+      title_doc: title_doc || title
+    }
+  end
+
+  defp normalize_search_data!(nil), do: nil
+
+  defp normalize_search_data!(search_data) when is_list(search_data) do
+    search_data_keys = [:anchor, :body, :title, :type]
+
+    Enum.each(search_data, fn search_data ->
+      has_keys = Map.keys(search_data)
+
+      if Enum.sort(has_keys) != search_data_keys do
+        raise ArgumentError,
+              "Expected search data to be a list of maps with the keys: #{inspect(search_data_keys)}, found keys: #{inspect(has_keys)}"
+      end
+    end)
+
+    search_data
+  end
+
+  defp normalize_search_data!(search_data) do
+    search_data_keys = [:anchor, :body, :title, :type]
+
+    raise ArgumentError,
+          "Expected search data to be a list of maps with the keys: #{inspect(search_data_keys)}, found: #{inspect(search_data)}"
+  end
+
+  defp extension_name(input) do
+    input
+    |> Path.extname()
+    |> String.downcase()
+  end
+
+  defp filename_to_title(input) do
+    input |> Path.basename() |> Path.rootname()
+  end
+
+  defp extra_type(".cheatmd"), do: :cheatmd
+  defp extra_type(".livemd"), do: :livemd
+  defp extra_type(_), do: :extra
+
+  @doc """
+  Generate assets from configs with the given default assets.
+  """
+  def generate_assets(namespace, defaults, %{output: output, assets: assets}) do
+    namespaced_assets =
+      if is_map(assets) do
+        Enum.map(assets, fn {source, target} -> {source, Path.join(namespace, target)} end)
+      else
+        IO.warn("""
+        giving a binary to :assets is deprecated, please give a map from source to target instead:
+
+            #{inspect(assets: %{assets => "assets"})}
+        """)
+
+        [{assets, Path.join(namespace, "assets")}]
+      end
+
+    Enum.flat_map(defaults ++ namespaced_assets, fn {dir_or_files, relative_target_dir} ->
+      target_dir = Path.join(output, relative_target_dir)
+      File.mkdir_p!(target_dir)
+
+      cond do
+        is_list(dir_or_files) ->
+          Enum.map(dir_or_files, fn {name, content} ->
+            target = Path.join(target_dir, name)
+            File.write(target, content)
+            Path.relative_to(target, output)
+          end)
+
+        is_binary(dir_or_files) and File.dir?(dir_or_files) ->
+          dir_or_files
+          |> File.cp_r!(target_dir, dereference_symlinks: true)
+          |> Enum.reduce([], fn path, acc ->
+            # Omit directories in .build file
+            if File.dir?(path) do
+              acc
+            else
+              [Path.relative_to(path, output) | acc]
+            end
+          end)
+          |> Enum.reverse()
+
+        is_binary(dir_or_files) ->
+          []
+
+        true ->
+          raise ":assets must be a map of source directories to target directories"
+      end
+    end)
+  end
+
+  @doc """
+  Generates the logo from config into the given directory.
+  """
+  def generate_logo(_dir, %{logo: nil}) do
+    []
+  end
+
+  def generate_logo(dir, %{output: output, logo: logo}) do
+    generate_image(output, dir, logo, "logo")
+  end
+
+  @doc """
+  Generates the cover from config into the given directory.
+  """
+  def generate_cover(_dir, %{cover: nil}) do
+    []
+  end
+
+  def generate_cover(dir, %{output: output, cover: cover}) do
+    generate_image(output, dir, cover, "cover")
+  end
+
+  def generate_image(output, dir, image, name) do
+    extname =
+      image
+      |> Path.extname()
+      |> String.downcase()
+
+    if extname in ~w(.png .jpg .jpeg .svg) do
+      filename = Path.join(dir, "#{name}#{extname}")
+      target = Path.join(output, filename)
+      File.mkdir_p!(Path.dirname(target))
+      File.copy!(image, target)
+      [filename]
+    else
+      raise ArgumentError, "image format not recognized, allowed formats are: .png, .jpg, .svg"
+    end
+  end
+end