build.rs

use std::process::Command;

fn main() {
    // Capture git hash (short form)
    let git_hash = Command::new("git")
        .args(["rev-parse", "--short=7", "HEAD"])
        .output()
        .ok()
        .and_then(|output| String::from_utf8(output.stdout).ok())
        .map(|s| s.trim().to_string())
        .unwrap_or_else(|| "unknown".to_string());

    // Capture build date (YYYY-MM-DD format)
    let build_date = chrono::Utc::now().format("%Y-%m-%d").to_string();

    // Set environment variables for compile-time access
    println!("cargo:rustc-env=GIT_HASH={}", git_hash);
    println!("cargo:rustc-env=BUILD_DATE={}", build_date);

    // Rerun if git HEAD changes
    println!("cargo:rerun-if-changed=.git/HEAD");
}