Question

I have some functions that deal with data provided in array format. These functions all do the same job, so I would like to merge them into a single function.

The problem is, each of them receives arrays with different depths: one-, two- and three-dimensional arrays are used and, in some future implementations, even four-dimensional arrays may be used.

In any case, the significant and necessary data are always in the two innermost arrays, so I need to get rid of the outer arrays until I have only the innermost two-levels.
My doubt is not simply how to do it, but how to do it elegantly and efficiently, as I find my current method rather clumsy.

Current method:

function add() {
    $data = func_get_args();
    if(count($data)>0) {
        if(is_array($data[0])) {
            if(is_array($data[0][0])) {
                foreach($data[0] as $row) {
                    $this->items[] = $row;
                }
            } else {
                $this->items[] = $data[0];
            }
        } else {
            $this->items[] = $data;
        }
    }
} 

Some use examples:

$list->add('one', 'two', 'three', 'four', 'five');

$list->add($data_from_DB_in_array_format);

$list->add(
    array(
        array('one', 'two', 'three', 'four', 'five'),
        array('six', 'seven', 'eight', 'nine', 'ten')
        )
    );

$list->add(
    array(
        array(
            array('one', 'two', 'three', 'four', 'five'),
            array('six', 'seven', 'eight', 'nine', 'ten')
            )
        )
    );

As the data is recovered via func_get_args(), everything is put inside an extra array.

The result must be something like this:

    array(
        array('one', 'two', 'three', 'four', 'five'),
        array('six', 'seven', 'eight', 'nine', 'ten')
        );

Answer 1

There is only one way you can achieve this, and it is with recursiveness and a little array function magic. It is probably not your exact solution but should get you started, if you need more help buzz me:

<?php

$data = array(
    'test1' => array(
        'test2' => array(
            'test3' => array(
                'test4' => array(
                    1,
                    2,
                    3
                ),
                'test5' => array(
                    4,
                    5,
                    6
                ),
                'test6' => array(
                    7,
                    8,
                    9
                ),
            )
        )
    )

);
function returnLast2Levels($item){
   if(is_array($item) && is_array(reset($item)) && is_array(reset(reset($item)))){
      //This $item has more than 2 levels, delve deeper
      return returnLast2Levels(reset($item));
   }elseif(is_array($item) && is_array(reset($item)) && !is_array(reset(reset($item)))){
      //This $item has 2 levels deep of array
      return $item;
   }
}

var_dump(returnLast2Levels($data));