<?php
function toBase62($num) {
    $chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    $result = "";
    while ($num > 0) {
        $result = $chars[$num % 62] . $result;
        $num = floor($num / 62);
    }
    return $result;
}

function generateID() {
    $epochStart = strtotime('2020-01-01') * 1000;
    $now = round(microtime(true) * 1000) - $epochStart;
    $random = rand(0, 999); // 3-digit random number
    $id = ($now * 1000) + $random; // Combine timestamp + randomness
    return substr(str_pad(toBase62($id), 8, "0", STR_PAD_LEFT), 0, 8); // Ensure 8 chars
}

echo generateID(); // Example output: "4D7hF2L3"
?>