module MasterView
  module Directives

    # creates a image_tag.
    # if path is specified in attr_value then it will be used exactly as listed, otherwise if attr_value is empty
    # then masterview will attempt to find the public/images in the string and infer the path from what follows.
    # otherwise it will simply use the src path.
    # If both width and height attr values are specified then it will build the :size option from them.
    # Other html attributes will be passed into image_tag options.
    class ImageTag < MasterView::DirectiveBase

      # /public\/images\/(.*)/
      IMAGE_SRC_EXTRACT_REGEX = MasterView::ConfigSettings.template_asset_base_ref_pattern[:images]

      metadata :priority => :default,
        :category => 'asset',
        :description => 'Replaces the element using the Rails image_tag helper.',
        :element_usage => 'img'

      attr_arg :src
      attr_arg :options, :append_element_attrs => [:common_html]

      event :element do
        if (@src.nil? or @src.empty?) and src_attr = element_attrs[:src]
          if match = IMAGE_SRC_EXTRACT_REGEX.match(src_attr)
            @src = match[1]
          else
            @src = src_attr
          end
        end
        @src = quote(@src) unless @src.nil?
        render erb_content('image_tag', :src, :options)
      end

    end

  end
end