php - Can't figure out the usort logic based on 2 variables -

i have array of objects (goals) want sort based on 2 of properties, status , duedate.

here rules:

statuses:

1. design
2. approved
3. in progress
4. completed
5. archived

if goal has status of 4 (completed) or 5 (archived) duedate doesn't matter.

if goal neither 4 nor 5 , duedate less "overdue" , should @ top

if goal not "overdue" order of statuses determines it's position (lowest highest)

if $a , $b both "overdue" 1 earliest duedate more important

the order should be:

1. overdue
2. design
3. approved
4. in progress
5. completed
6. archived

here last thing tried:

function cmp($a, $b) {     $now = new datetime("now");     $aduedate = new datetime($a->getduedate());     $bduedate = new datetime($b->getduedate());  if($a->getstatus() != 4 && $a->getstatus() != 5 && $b->getstatus() != 4 && $b->getstatus() != 5){     if($aduedate < $now || $bduedate < $now){         if($aduedate == $bduedate){         return 0;     }      return ($aduedate < $bduedate) ? -1 : 1;     } } elseif(($a->getstatus() == 4 || $a->getstatus() == 5) && ($b->getstatus() != 4 && $b->getstatus() != 5)) {     return -1; } elseif(($a->getstatus() != 4 && $a->getstatus() != 5) && ($b->getstatus() == 4 || $b->getstatus() == 5)){     return 1; }  if ($a->getstatus() == $b->getstatus()) {         return 0;     }     return ($a->getstatus() < $b->getstatus()) ? -1 : 1; } 

which orders array so:

1. completed
2. archived
3. overdue
4. design
5. approved
6. in progress

the following should meet requirements:

function cmp($a, $b) {     $now = new datetime("now");     $aduedate = new datetime($a->getduedate());     $bduedate = new datetime($b->getduedate());     $astatus = $a->getstatus();     $bstatus = $b->getstatus();     $incompletestatuses = array(1, 2, 3);       // use date if same status (might not needed)         if ($astatus == $bstatus) {         return ($aduedate < $bduedate ? -1 : 1);      }         // if overdue:     if (in_array($astatus, $incompletestatuses) && $aduedate < $now) {         // if b overdue too, consider dates         if (in_array($bstatus, $incompletestatuses) && $bduedate < $now) {             return ($aduedate < $bduedate ? -1 : 1);          }             return -1; // first     }        // if b overdue:     elseif (in_array($bstatus, $incompletestatuses) && $bduedate < $now) {         return 1; // b first (we know not overdue above)     }         // both , b not overdue; order status     return $astatus - $bstatus; } 

here's test codepad.