class ActionDispatch::Journey::Router

def ast
  routes.ast
end

def custom_routes
  partitioned_routes.last
end

def filter_routes(path)
  return [] unless ast
  simulator.memos(path) { [] }
end

def find_routes req
  routes = filter_routes(req.path_info).concat custom_routes.find_all { |r|
    r.path.match(req.path_info)
  }
  routes =
    if req.request_method == "HEAD"
      match_head_routes(routes, req)
    else
      match_routes(routes, req)
    end
  routes.sort_by!(&:precedence)
  routes.map! { |r|
    match_data  = r.path.match(req.path_info)
    path_parameters = r.defaults.dup
    match_data.names.zip(match_data.captures) { |name,val|
      path_parameters[name.to_sym] = Utils.unescape_uri(val) if val
    }
    [match_data, path_parameters, r]
  }
end

def initialize(routes)
  @routes = routes
end

def match_head_routes(routes, req)
  verb_specific_routes = routes.reject { |route| route.verb == // }
  head_routes = match_routes(verb_specific_routes, req)
  if head_routes.empty?
    begin
      req.request_method = "GET"
      match_routes(routes, req)
    ensure
      req.request_method = "HEAD"
    end
  else
    head_routes
  end
end

def match_routes(routes, req)
  routes.select { |r| r.matches?(req) }
end

def partitioned_routes
  routes.partitioned_routes
end

def recognize(rails_req)
  find_routes(rails_req).each do |match, parameters, route|
    unless route.path.anchored
      rails_req.script_name = match.to_s
      rails_req.path_info   = match.post_match.sub(/^([^\/])/, '/\1')
    end
    yield(route, parameters)
  end
end

def serve(req)
  find_routes(req).each do |match, parameters, route|
    set_params  = req.path_parameters
    path_info   = req.path_info
    script_name = req.script_name
    unless route.path.anchored
      req.script_name = (script_name.to_s + match.to_s).chomp('/')
      req.path_info = match.post_match
      req.path_info = "/" + req.path_info unless req.path_info.start_with? "/"
    end
    req.path_parameters = set_params.merge parameters
    status, headers, body = route.app.serve(req)
    if 'pass' == headers['X-Cascade']
      req.script_name     = script_name
      req.path_info       = path_info
      req.path_parameters = set_params
      next
    end
    return [status, headers, body]
  end
  return [404, {'X-Cascade' => 'pass'}, ['Not Found']]
end

def simulator
  routes.simulator
end

def visualizer
  tt     = GTG::Builder.new(ast).transition_table
  groups = partitioned_routes.first.map(&:ast).group_by { |a| a.to_s }
  asts   = groups.values.map { |v| v.first }
  tt.visualizer(asts)
end