PHP error with too many IF statements, need second view

Im lost in if, else statments and cant figure out right syntax with obviously simple problem.

i have 3 situations, code which i looking for is saved in DTB, OR hardcoded and code start CODE_1-OR no code at all.

first defined variable $code

$code = Discount::where('code',$discount_code)

1] lets check if variable $code is in database or return 0

if (!is_null($code) !== false){
   $response['discount'] = $code->discount;
   } else {
     $response['valid'] = false;
     $response['discount'] = 0;          
    

2] variable isnt in DTB but is hardcoded CODE_1- this type of codes always start at CODE_1- so function strpos can help

and there start my problem, code isnt in datebase

if (is_null($code) = (strpos($discount_code, 'CODE-')) {
    $response['valid'] = true;
    $response['discount'] = 50;

3] Code isnt hardoced or saved in databese

?

can be all this conditions merged together ?