inanzzz | Sorting multidimensional array by two different keys or values depending on priority

Say you have an unordered multidimensional array and want to order it by two different keys or values depending on priority. Example below does what you want.

Rules

Primary: True is better than False.

Age: The greater the better.

Primary overrides Age

Raw array

$array = [
	'Z' => [
		'primary' => true,
		'age' => 55
	],
	'C' => [
		'primary' => false,
		'age' => 60
	],
	'K' => [
		'primary' => true,
		'age' => 60
	],
	'S' => [
		'primary' => false,
		'age' => 40
	],
	'F' => [
		'primary' => true,
		'age' => 60
	],
	'A' => [
		'primary' => true,
		'age' => 30
	]
];

Aim

$aim =  [
	'F' => [
		'primary' => true,
		'age' => 60
	],
	'K' => [
		'primary' => true,
		'age' => 60
	],
	'Z' => [
		'primary' => true,
		'age' => 55
	],
	'A' => [
		'primary' => true,
		'age' => 30
	],
	'C' => [
		'primary' => false,
		'age' => 60
	],
	'S' => [
		'primary' => false,
		'age' => 40
	]
];

Function

uasort($array, function($a, $b) {
	if ($b['primary'] === $a['primary']) {
		return $b['age'] > $a['age'];
	}
	
    return strcmp($b['primary'], $a['primary']);
});

print_r($array);

Result

(
    [F] => Array
        (
            [primary] => 1
            [age] => 60
        )

    [K] => Array
        (
            [primary] => 1
            [age] => 60
        )

    [Z] => Array
        (
            [primary] => 1
            [age] => 55
        )

    [A] => Array
        (
            [primary] => 1
            [age] => 30
        )

    [C] => Array
        (
            [primary] => 
            [age] => 60
        )

    [S] => Array
        (
            [primary] => 
            [age] => 40
        )
)