require 'digest/sha1'

module Awestruct
  module Extensions
    class Disqus

      def execute(site)
        site.pages.each{ |p| p.extend Disqus }
      end

      module Disqus

        def disqus_comments()
          identifier = "null"
          if self.disqus_identifier or site.disqus_generate_id
            identifier = %Q("#{self.resolve_disqus_identifier()}")
          end
          %Q{
            <div id="disqus_thread"></div>
            <script type="text/javascript">
            var disqus_shortname = '#{site.disqus}';
            var disqus_url = "#{site.base_url}#{self.url}";
            var disqus_developer = #{site.disqus_developer ? 1 : "null"};
            var disqus_identifier = #{identifier};
            (function() {
              var dsq = document.createElement("script"); dsq.type = "text/javascript"; dsq.async = true;
              dsq.src = '//' + disqus_shortname + '.disqus.com/embed.js';
              (document.getElementsByTagName("head")[0] || document.getElementsByTagName("body")[0]).appendChild(dsq);
            })();
            </script>
            <noscript>Please enable JavaScript to view the <a href="http://disqus.com/?ref_noscript=#{site.disqus}">comments powered by Disqus.</a></noscript>
          }
        end

        def disqus_comments_link()
          identifier = ''
          if self.disqus_identifier or site.disqus_generate_id
            identifier = %Q{ data-disqus-identifier="#{self.resolve_disqus_identifier()}"}
          end
          %Q{ <a href="#{site.base_url}#{self.url}#disqus_thread"#{identifier}>Comments</a> }
        end

        def disqus_comments_count()
          %Q{
            <script type="text/javascript">
            var disqus_shortname = '#{site.disqus}';
            (function () {
              var s = document.createElement('script'); s.async = true;
              s.src = '//' + disqus_shortname + '.disqus.com/count.js';
              (document.getElementsByTagName('HEAD')[0] || document.getElementsByTagName('BODY')[0]).appendChild(s);
            }());
            </script>
          }
        end

        def resolve_disqus_identifier()
          self.disqus_identifier ? self.disqus_identifier : Digest::SHA1.hexdigest(self.date.strftime('%Y-%m-%d-') + self.slug)
        end

      end
    end
  end
end