# frozen_string_literal: true
require 'sprockets/autoload'
require 'sprockets/digest_utils'
require 'sprockets/source_map_utils'

module Sprockets
  # Public: Uglifier/Uglify compressor.
  #
  # To accept the default options
  #
  #     environment.register_bundle_processor 'application/javascript',
  #       Sprockets::UglifierCompressor
  #
  # Or to pass options to the Uglifier class.
  #
  #     environment.register_bundle_processor 'application/javascript',
  #       Sprockets::UglifierCompressor.new(comments: :copyright)
  #
  class UglifierCompressor
    VERSION = '3'

    # Public: Return singleton instance with default options.
    #
    # Returns UglifierCompressor object.
    def self.instance
      @instance ||= new
    end

    def self.call(input)
      instance.call(input)
    end

    def self.cache_key
      instance.cache_key
    end

    attr_reader :cache_key

    def initialize(options = {})
      options[:comments] ||= :none

      @options = options
      @cache_key = "#{self.class.name}:#{Autoload::Uglifier::VERSION}:#{VERSION}:#{DigestUtils.digest(options)}".freeze
    end

    def call(input)
      case Autoload::Uglifier::VERSION.to_i
      when 1
        raise "uglifier 1.x is no longer supported, please upgrade to 2.x or newer"
      when 2
        input_options = { source_filename: input[:filename] }
      else
        input_options = { source_map: { filename: input[:filename] } }
      end

      uglifier = Autoload::Uglifier.new(@options.merge(input_options))

      js, map = uglifier.compile_with_map(input[:data])

      map = SourceMapUtils.format_source_map(JSON.parse(map), input)
      map = SourceMapUtils.combine_source_maps(input[:metadata][:map], map)

      { data: js, map: map }
    end
  end
end