begin
  require 'uglifier'
rescue LoadError
  puts "UglifyJS not available. Install it with: gem install uglifier"
end

module Middleman
  module Rack

    class MinifyJavascript
      def initialize(app, options={})
        @app = app
      end

      def call(env)
        status, headers, response = @app.call(env)

        if env["PATH_INFO"].match(/\.js$/)
          compressor = ::Uglifier.new

          if response.is_a?(::Rack::File) or response.is_a?(Sinatra::Helpers::StaticFile)
            uncompressed_source = File.read(response.path)
          else
            uncompressed_source = response.join
          end
          minified = compressor.compile(uncompressed_source)
          headers["Content-Length"] = ::Rack::Utils.bytesize(minified).to_s
          response = [minified]
        end

        if env["PATH_INFO"].match(/\.html$/)
          compressor = ::Uglifier.new

          if response.is_a?(::Rack::File) or response.is_a?(Sinatra::Helpers::StaticFile)
            uncompressed_source = File.read(response.path)
          else
            uncompressed_source = response.join
          end

          minified = uncompressed_source.gsub(/(<scri.*?\/\/<!\[CDATA\[\n)(.*?)(\/\/\]\].*?<\/script>)/m) do |m|
            first = $1
            uncompressed_source = $2
            last = $3
            minified_js = compressor.compile(uncompressed_source)

            first << minified_js << "\n" << last
          end
          headers["Content-Length"] = ::Rack::Utils.bytesize(minified).to_s
          response = [minified]
        end

        [status, headers, response]
      end
    end

  end
end