use std::process::Command;

fn main() {
    // Re-run if git HEAD changes (new commit)
    println!("cargo:rerun-if-changed=.git/HEAD");
    println!("cargo:rerun-if-changed=.git/refs/heads/");

    let version = env!("CARGO_PKG_VERSION");

    let short_sha = Command::new("git")
        .args(["rev-parse", "--short", "HEAD"])
        .output()
        .ok()
        .filter(|o| o.status.success())
        .and_then(|o| String::from_utf8(o.stdout).ok())
        .map(|s| s.trim().to_string());

    let full_version = match short_sha {
        Some(sha) => format!("{}-{}", version, sha),
        None => version.to_string(),
    };

    println!("cargo:rustc-env=GRAIN_VERSION={}", full_version);
}