module Locomotive
  module Liquid
    module Tags
      class WithScope < ::Liquid::Block

        def initialize(tag_name, markup, tokens, context)
          @attributes = {}
          markup.scan(::Liquid::TagAttributes) do |key, value|
            @attributes[key] = value
          end
          super
        end

        def render(context)
          context.stack do
            context['with_scope'] = decode(@attributes, context)
            render_all(@nodelist, context)
          end
        end

        private

        def decode(attributes, context)
          attributes.each_pair do |key, value|
            attributes[key] = (case value
            when /^true|false$/i then value == 'true'
            when /^[0-9]+$/ then value.to_i
            when /^["|'](.+)["|']$/ then $1.gsub(/^["|']/, '').gsub(/["|']$/, '')
            else
              context[value]
            end)
          end
        end
      end

      ::Liquid::Template.register_tag('with_scope', WithScope)
    end
  end
end