Making random fair again - for sorin

fair_random.php

<?php

$original = $elements = [
    'A' => 100,
    'B' => 80,
    'C' => 60,
    'D' => 5,
];

function chooseElementFromWeightedList(array $list)
{
    $overallProbability = array_sum($list);

    $point = rand(0, $overallProbability);

    asort($list);

    $tmp = 0;

    foreach ($list as $element => $weight) {
        if ($point < ($weight + $tmp)) {
            return $element;
        }
        $tmp += $weight;
    }
    return $element;
}

function shouldReset(array $elements, array $stats): bool
{
    foreach ($elements as $element => $score) {
        if (!isset($stats[$element])) {
            return false;
        }
        if ($stats[$element] <= $score) {
            return false;
        }
    }
    return true;
}


for ($i = 0; $i < 1000; $i++) {
    $selected = chooseElementFromWeightedList($elements);
    foreach ($elements as $element => &$score) {
        if ($element !== $selected) {
            $score++;
        }
    }
    unset($score);
    $elements[$selected] = $original[$selected];
}