defmodule Sass do
  @moduledoc """
  Compiles SASS into CSS using a NIF for Libsass

  ## Currently supported Sass options

  * [output_style](http://sass-lang.com/documentation/file.SASS_REFERENCE.html#output_style) Use the helpers below to assign the style
  * precision `integer` - decimal rounding percision
  * source_comments `true` or `false` - Causes the line number and file where a selector is defined to be emitted into the compiled CSS as a comment
  * soure_map_embed `true` or `false`
  * source_map_contents `true` or `false`
  * omit_source_map_url `true` or `false`
  * is_indented_syntax `true` or `false`
  * indent `:tab` or `:space`
  * linefeed `:unix` or `:windows`
  * include_paths list of directorys for Sass to search for imports ex

      `["bower_compoents", "../node_modules"]`

  """

  alias Sass.Compiler, as: Compiler

  # Sass option values for sass [output style](https://sass-lang.com/documentation/js-api#outputstyle)
  @sass_styles [
    compact: 2,
    compressed: 3,
    expanded: 1,
    nested: 0
  ]

  @doc """
  Compiles a string of CSS/SCSS/Sass into CSS string

  ## Examples

      iex> sass = "$white : #fff; a { color: $white;}"
      iex> Sass.compile(sass)
      {:ok, "a {\n  color: #fff; }\n"}

      # With options
      iex> Sass.compile(sass, %{output_style: 2})
      {:ok, "a { color: #fff; }\n"}

  """
  def compile(source, options \\ %{output_style: default_style()}) do
    source
    |> String.trim()
    |> Compiler.compile(options)
  end

  @doc """
  Compiles a file with CSS/SCSS/Sass into CSS string

  ## Examples

      iex> Sass.compile_file("application.scss")
      {:ok, "a {\n  color: #fff; }\n"}

      # With options
      iex> Sass.compile_file("application.scss", %{output_style: 3})
      {:ok, "a{color:#fff}\n"}

  """
  def compile_file(path, options \\ %{output_style: default_style()}) do
    path
    |> String.trim()
    |> Compiler.compile_file(options)
  end

  def styles, do: @sass_styles

  def version, do: Compiler.version()

  defp default_style, do: @sass_styles[:expanded]
end