Generate offline UUID for Minecraft player in Rust

example.rs

use md5::{Md5, Digest};
use std::fmt::Write;

fn build_uuid(username: &str) -> String {
    let mut hasher = Md5::new();
    hasher.update(format!("OfflinePlayer:{}", username).as_bytes());

    let result = hasher.finalize();
    let mut data = result.into_iter().collect::<Vec<u8>>();

    data[6] = (data[6] & 0x0f) | 0x30;
    data[8] = (data[8] & 0x3f) | 0x80;

    to_formatted(&data)
}

fn to_formatted(data: &[u8]) -> String {
    let mut hex_string = String::new();
    for byte in data {
        write!(&mut hex_string, "{:02x}", byte).unwrap();
    }

    format!(
        "{}-{}-{}-{}-{}",
        &hex_string[0..8],
        &hex_string[8..12],
        &hex_string[12..16],
        &hex_string[16..20],
        &hex_string[20..32]
    )
}