router.erl

-module(router).

-export([g/0]).

%% [{attribute,1,file,
%%             {"/home/arjan/devel/zotonic/src/router.erl",1}},
%%  {attribute,1,module,router},
%%  {attribute,1,lager_records,[]},
%%  {attribute,3,export,[{route,1}]},
%%  {function,5,route,1,
%%            [{clause,5,
%%                     [{nil,5}],
%%                     [],
%%                     [{tuple,6,
%%                             [{atom,6,name},
%%                              {atom,6,controller_template},
%%                              {cons,6,{tuple,6,[...]},{nil,6}}]}]}]},

-define(ROUTER_MOD, z_dispatch_router).

-include_lib("wm_host_dispatch_list.hrl").

g() ->
    Rules = z_sites_dispatcher:collect_dispatchrules(),
    Forms = [{attribute, 0, module, ?ROUTER_MOD},
             {attribute,3,export,[{get_dispatch_alias,1}]},
             generate_dispatch_alias_fn(Rules)],

    {ok, ?ROUTER_MOD, Binary} = compile:forms(Forms),
    code:load_binary(?ROUTER_MOD, "z_dispatch_router.gen.erl", Binary).


generate_dispatch_alias_fn(Rules) ->
    {function, 0, get_dispatch_alias, 1,
     lists:flatten(
       [
        [{clause, 0, [erl_parse:abstract(WM#wm_host_dispatch_list.hostname)], [], [erl_parse:abstract(WM#wm_host_dispatch_list.hostname)]}]
        ++
        [{clause, 0, [erl_parse:abstract(A)], [], [erl_parse:abstract(WM#wm_host_dispatch_list.hostname)]}
         || A <- WM#wm_host_dispatch_list.hostalias]
        || WM <- Rules]
      ) ++
         [{clause, 0, [{var, 0, '_'}], [], [{atom, 0, undefined}]}]
         
    }.