Incrementing through a MYSQL result set without stopping - php

Question

I am trying to increment through a result set from my table.
I attempt to display the next three results using an increment. This is working fine.
For example;
current = 5.
It then displays the next three: 6,7,8
It can also display the previous three: 4,3,2
The problem comes when I reach the last couple or minimum couple of results. It will currently stop;
current = 23
next: 24, 25
I cannot figure out to loop through to the last or first few results.
E.g. I want it to do this:
current = 2
display previous three: 1, 25, 24
AND FOR next:
current = 23:
display next three: 24, 25, 1
I'm returning these as arrays. Code:
$test_array = array();
$no = 1;
while($results=mysql_fetch_assoc($test_query))
{
$test_array[] = array('test_id' => $results['id'],
'path' => $results['Path'],
'type' => $results['FileType']
'no' => $no);
$no++;
}
$current_no = 0;
if(is_array($test_array) && count($test_array)>0)
{
foreach($test_array as $key=>$array)
{
if($array['test_id']==intval($db_res['current_id']))
{
$current[] = $array;
$current_no = intval($key+1);
}
else
//error
if(intval($current_no)>0)
{
//Next 3
for($i=0;$i<3;$i++)
{
if(isset($test_array[intval($current_no+$i)]) && is_array($test_array[intval($current_no+$i)]))
{
$next[] = $test_array[intval($current_no+$i)];
}
else
break;
}
//Previous 3
for($i=2;$i<5;$i++)
{
if(isset($test_array[intval($current_no-$i)]) && is_array($test_array[intval($current_no-$i)]))
{
$previous[] = $test_array[intval($current_no-$i)];
}
else
break;
}
break;
}
else
//error
}
}
else
//error
If anyone has any ideas on how to help, that would be great!

Answer 1

Find $key for $current and set $next_key = $prev_key = $key;
Find last key $max = count($test_array) - 1;
Increase $next_key & decrease $prev_key 3 times (and check if
boundary is reached):
Loop might look like this.
for ($i = 1; $i <= 3; $i++)
{
$next_key = ($next_key == $max) ? 0 : $next_key + 1;
$prev_key = ($prev_key == 0) ? $max : $prev_key - 1;
$next[] = $test_array[$next_key];
$prev[] = $test_array[$prev_key];
}