php语法如何实现概率抽奖功能？

<?php
$prize = [
    ['name' => 'iphone13', 'chance' => 100],
    ['name' => '佳能相机', 'chance' => 900],
    ['name' => '洗碗机', 'chance' => 1000],
    ['name' => '加班一天', 'chance' => 2000],
    ['name' => '谢谢参与', 'chance' => 3000]
];
  
// 概率重组
$chance = 0;
foreach ($prize as &$item) {
    $chance += $item['chance'];
    $item['chance'] = $chance;
}  

// 随机抽奖
$rand = mt_rand(1, 10000);  
$result = [];
foreach ($prize as $_k => $_v) {
    if ($_k == 0) {
        if ($rand > 0 && $rand <= $_v['chance']) {
            $result = $_v;
            break;
        }
    } else {
        if ($rand > $prize[$_k - 1]['chance'] && $rand <= $_v['chance']) {
            $result = $_v;
            break;
        }
    }
}
  
// 抽奖结果
echo json_encode(compact('rand', 'result'));