link_to flexibility

My website, user side, is just one controller/action

I reroute this:

to this:

so that the visitors have a nice web url like this:

all menu and submenu is dynamically generate from a database, the
whole website is actually contained in the database...

the problem is that I don't know how to use the link_to helper in this situation

<%= link_to, {:controller => 'mycontroller', :action =>
'index', :menu =>} %>

results in:

which works but sucks

I could do this, but I have to create a @site variable and set it everytime

<a href="<%= @site + %>"><%= %></a>

How would you solve the problem? Any idea, suggestion...

<a href=" "><%= %></a>