use std::time::{SystemTime, UNIX_EPOCH};

fn utc_ymd_from_unix_secs(secs: i64) -> (i32, u32, u32) {
    let days = secs.div_euclid(86_400);
    let z = days + 719_468;
    let era = if z >= 0 { z } else { z - 146_096 } / 146_097;
    let doe = z - era * 146_097;
    let yoe = (doe - doe / 1_460 + doe / 36_524 - doe / 146_096) / 365;
    let mut y = yoe + era * 400;
    let doy = doe - (365 * yoe + yoe / 4 - yoe / 100);
    let mp = (5 * doy + 2) / 153;
    let d = doy - (153 * mp + 2) / 5 + 1;
    let m = mp + if mp < 10 { 3 } else { -9 };
    y += if m <= 2 { 1 } else { 0 };
    (y as i32, m as u32, d as u32)
}

fn main() {
    let secs = match SystemTime::now().duration_since(UNIX_EPOCH) {
        Ok(d) => d.as_secs() as i64,
        Err(_) => 0,
    };
    let (y, m, d) = utc_ymd_from_unix_secs(secs);
    println!("cargo:rustc-env=TRX_SERVER_BUILD_DATE={y:04}-{m:02}-{d:02}");
}