<?php

function parseMetadata ($metadata) {
    $metadata["little"] = 0;

    $age = -1;

    if (isset($metadata["birth"]["age"]) && $metadata["birth"]["age"] !== 0) {
        $age = $metadata["birth"]["age"];
    } else if (isset($metadata["birth"]["year"]) && $metadata["birth"]["year"] > 1990) {
        $age = (int)date('Y') - $metadata["birth"]["year"] + (strtotime(date('Y') . "-" . $metadata["birth"]["date"]) <= time() ? 0 : -1);
    }

    if (is_string($age) && isset(explode("-", $age)[1]) && is_numeric(explode("-", $age)[1])) {
        $age = (int)explode("-", $age)[1];
    }

    if ($age > 0 && $age <= 10) {
        $metadata["little"] = 2;
    } else if ($age > 0 && $age <= 15) {
        $metadata["little"] = 3;
    }

    return $metadata;
}