module Jangle
  class HashEndpointRouter

    def initialize(routes)
      @routes = routes
    end
    
    # Consumes the parts of the request path, finding the next hash
    # or an endpoint; returns the endpoint identified by that sequence of path parts
    #
    # For example, the hash might look like this:
    #   {'base' => {
    #               'one' => HttpEndpoint.new(:host => 'localhost', :port => 8080),
    #               'two' => HttpEndpoint.new(:host => 'localhost', :port => 4000)
    #              },
    #    'other' => {
    #                'three' => HttpEndpoint.new(:host => 'localhost')
    #               }
    #   }
    # 
    # which would be able to route /base/one, /base/two, /other/three to those three
    # endpoints
    def route(request)
      path_parts = request.path_info.split('/')
      path_parts.shift

      if path_parts.empty?
        path_remaining = '/'
        service = @routes['_root_']
      else
        path_parts_remaining, service = do_routing(@routes, path_parts)
        path_remaining = '/' + path_parts_remaining.join('/')
      end
      return [path_remaining, service]
    end
    
    private
    def do_routing(route_or_dest, path_parts)
      while route_or_dest.respond_to?(:has_key?) and route_or_dest.has_key?(path_parts[0])
        route_or_dest = route_or_dest[path_parts.shift]
      end

      if route_or_dest.respond_to?(:serve)
        service = route_or_dest
      else
        service = route_or_dest['_root_']
      end

      [path_parts, service]
    end
  end
end