Codeigniter passing parameter to controller index - php

Question

I'm building a tutorialsystem with codeigniter and would like to achieve the following URL structure:
/tutorials --> an introduction page with the list of all the categories
/tutorials/{a category as string} --> this will give a list of tutorials for the given category, e.g. /tutorials/php
/tutorials/{a category as string}/{an ID}/{tutorial slug} --> this will show the tutorial, e.g. /tutorials/php/123/how-to-use-functions
/tutorials/add --> page to add a new tutorial
The problem is that when I want to use the first two types of URLs, I'd need to pass parameters to the index function of the controller. The first parameter is the optional category, the second is the optional tutorial ID. I've did some research before I posted, so I found out that I could add a route like tutorials/(:any), but the problem is that this route would pass add as a parameter too when using the last URL (/tutorials/add).
Any ideas how I can make this happen?

Answer 1

Your routing rules could be in this order:
$route['tutorials/add'] = "tutorials/add"; //assuming you have an add() method
$route['tutorials/(:any)'] = "tutorials/index"; //this will comply with anything which is not tutorials/add
Then in your controller's index() method you should be able to work out whether it's the category or tutorial ID is being passed!

Answer 2

I do think that a remap must be of more use to your problem in case you want to add more methods to your controller, not just 'add'. This should do the task:
function _remap($method)
{
if (method_exists($this, $method))
{
$this->$method();
}
else {
$this->index($method);
}
}

Answer 3

A few minutes after posting, I think I've found a possible solution for this. (Shame on me).
In pseudo code:
public function index($cat = FALSE, $id = FALSE)
{
if($cat !== FALSE) {
if($cat === 'add') {
$this->add();
} else {
if($id !== FALSE) {
// Fetch the tutorial
} else {
// Fetch the tutorials for category $cat
}
}
} else {
// Show the overview
}
}
Feedback for this solution is welcome!