[Deprecated] DMZ 1.5.3 (DataMapper OverZealous Edition)

[eluser]tomdelonge[/eluser]
So I've got a simple little store I'm making. I want categories to be able to have categories. I really feel like this code is too cluttered and I'm not sure if It's the best way to do it.

So the url would look like this:

categories/view/5

10 products at a time should show up on a page. Here's my questions:
1) Should I clone an object (or even create a new one) just to find the current category? What's a better way?
2) Am I even getting the categories in the best ways (best sql queries?) I'm not going to be caching pages, so I want the best possible queries.
3) with the pagination, do I really need to do a whole other query just to find if another page is possible?

Basically, give me any suggestions that you have. Thanks. (This is my first project with dmz, if you can't tell from my code).

each product has_one category
each category has_many products

Code:

function view($id = NULL)
    {
        $array = $this->uri->uri_to_assoc(2);
        $page = element('page', $array);
        if ( ! $page)
        $page = 1;
        if( ! $id)
        {
            show_404();
        }
        else
        {
            $c = new Category();
            $c->get_by_id($id);
            
            if ( ! $c->exists())
            {
                show_404();
            }
            else
            {
                //the category exists
                //if it's the lowest one (has no children)
                //then find the products that go to it.
                $c = new Category();
                $current = $c->get_clone();
                //find all categories that have parent of $id
                $c->where('parent', $id)->get();
                if ( ! $c->exists())
                {
                    //no more children; display the products
                    $p = new Product();
                    $c = new Category();
                    $c->get_by_id($id);
                    
                    $limit = 10;
                    $offset = ($page * $limit) - $limit;
                    $c->product->get($limit, $offset);
        
                    $current->get_by_id($id);
                    $data['products'] = $c->product->all_to_array();
                    $data['current'] = $current->name;
                    $data['c'] = $c->all_to_array();
                    
                    $limit = 10;
                    $offset = (($page + 1) * $limit) - $limit;
                    $c->product->get($limit, $offset);
                    $data['next_page'] = FALSE;
                    if ($c->product->exists())
                    {
                        $data['next_page'] = $page + 1;
                    }
                    
                    $this->load->view('shopping/categories/view', $data);
                }
                else
                {
                
                }
            }
        }
    }