use std::process::Command;

fn git(args: &[&str]) -> Option<String> {
    let output = Command::new("git").args(args).output().ok()?;
    if !output.status.success() {
        return None;
    }
    let text = String::from_utf8(output.stdout).ok()?;
    Some(text.trim().to_string())
}

fn main() {
    println!("cargo:rerun-if-changed=.git/HEAD");
    println!("cargo:rerun-if-changed=.git/index");

    let hash = git(&["rev-parse", "--short=12", "HEAD"]).unwrap_or_else(|| "unknown".into());
    let date = git(&["show", "-s", "--format=%cs", "HEAD"]).unwrap_or_else(|| "unknown".into());
    let dirty = Command::new("git")
        .args(["diff", "--quiet", "--ignore-submodules", "--"])
        .status()
        .map(|status| if status.success() { "" } else { "+dirty" })
        .unwrap_or("");

    println!("cargo:rustc-env=DOSH_GIT_HASH={hash}{dirty}");
    println!("cargo:rustc-env=DOSH_COMMIT_DATE={date}");
}