class Pathutil
  module Helpers
    extend self

    # --

    def allowed
      return @allowed ||= begin
        {
          :yaml => {
            :classes => [],
            :symbols => []
          }
        }
      end
    end

    # --
    # Wraps around YAML and SafeYAML to provide alternatives to Rubies.
    # @note We default aliases to yes so we can detect if you explicit true.
    # @return Hash
    # --
    def load_yaml(data, safe: true, whitelist_classes: allowed[:yaml][:classes], \
        whitelist_symbols: allowed[:yaml][:symbols], aliases: :yes)

      require "yaml"
      unless safe
        return YAML.load(
          data
        )
      end

      if !YAML.respond_to?(:safe_load)
        setup_safe_yaml whitelist_classes, aliases
        SafeYAML.load(
          data
        )

      else
        YAML.safe_load(
          data,
          whitelist_classes,
          whitelist_symbols,
          aliases
        )
      end
    end

    # --
    # Make a temporary name suitable for temporary files and directories.
    # @return String
    # --
    def make_tmpname(prefix = "", suffix = nil, root = nil)
      prefix = tmpname_prefix(prefix)
      suffix = tmpname_suffix(suffix)

      root ||= Dir::Tmpname.tmpdir
      File.join(root, Dir::Tmpname.make_tmpname(
        prefix, suffix
      ))
    end

    # --

    private
    def tmpname_suffix(suffix)
      suffix = suffix.join("-") if suffix.is_a?(Array)
      suffix = suffix.gsub(/\A\-/, "") unless !suffix || suffix.empty?
      suffix
    end

    # --
    # Cleanup the temp name prefix, joining if necessary.
    # rubocop:disable Style/ParallelAssignment
    # --
    private
    def tmpname_prefix(prefix)
      ext, prefix = prefix, "" if !prefix.is_a?(Array) && prefix.start_with?(".")
      ext = prefix.pop if prefix.is_a?(Array) && prefix[-1].start_with?(".")
      prefix = prefix.join("-") if prefix.is_a?(Array)

      unless prefix.empty?
        prefix = prefix.gsub(/\-\Z/, "") \
          + "-"
      end

      return [
        prefix, ext || ""
      ]
    end

    # --
    # Wrap around, cleanup, deprecate and use SafeYAML.
    # rubocop:enable Style/ParallelAssignment
    # --
    private
    def setup_safe_yaml(whitelist_classes, aliases)
      warn "WARN: SafeYAML does not support disabling  of aliases." if aliases && aliases != :yes
      warn "WARN: SafeYAML will be removed when Ruby 2.0 goes EOL."
      require "safe_yaml/load"

      SafeYAML.restore_defaults!
      whitelist_classes.map(&SafeYAML.method(
        :whitelist_class!
      ))
    end
  end
end