Controller structure

[eluser]vps4[/eluser]
My site's navigation like this

Code:

admin
        A
            A1
            A2
                 A2A
                 A2B
            A3
        B
            B1
            B2
        C
        D

all of A, A1 A2A are function and with parameters
How design Controller?

Solution 1:
THE PROBLEM IS How can I design A2A function ?

"application/controller/admin.php"

Code:

class Admin extends Controller {

    function __construct() {
         parent::Controller();
    }

    function index() {
        // this is admin
    }

    function A($action = '', $page = 1) {
        // this is A
        // example uri : admin/A/do/2/
        // how can I design A2A function ?
    }

    function B($page = 1, $action = 'testB') {
        // this is B
        // example uri : admin/B/3/testB/
    }
}

Solution 2:

if I create "admin" folder in "application/controller/"
so the struct is
admin/A.php
admin/B.php
admin/C.php
...
and create A class

THE PROBLEM IS how can I set the admin default controller? admin is a dir. And I don't like to modify route config file.

A.php

Code:

class A extends Controller {

    function __construct() {
         parent::Controller();
    }

    function index() {
    }

    function A1($action = '', $page = 1)

    }