use std::env;
use std::process::Command;

fn main() {
    // Set build timestamp
    println!(
        "cargo:rustc-env=RUSTYTORCH_BUILD_TIMESTAMP={}",
        chrono::Utc::now().format("%Y-%m-%d %H:%M:%S UTC")
    );

    // Get git commit hash
    let git_commit = Command::new("git")
        .args(["rev-parse", "--short", "HEAD"])
        .output()
        .ok()
        .and_then(|output| {
            if output.status.success() {
                String::from_utf8(output.stdout).ok()
            } else {
                None
            }
        })
        .map_or_else(|| "unknown".to_string(), |s| s.trim().to_string());

    println!("cargo:rustc-env=RUSTYTORCH_GIT_COMMIT={git_commit}");

    // Get Rust version
    let rustc_version = env::var("RUSTC_VERSION").unwrap_or_else(|_| {
        Command::new(env::var("RUSTC").unwrap_or_else(|_| "rustc".to_string()))
            .arg("--version")
            .output()
            .ok()
            .and_then(|output| {
                if output.status.success() {
                    String::from_utf8(output.stdout).ok()
                } else {
                    None
                }
            })
            .map_or_else(|| "unknown".to_string(), |s| s.trim().to_string())
    });

    println!("cargo:rustc-env=RUSTYTORCH_RUST_VERSION={rustc_version}");

    // Get target architecture
    let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_else(|_| "unknown".to_string());
    println!("cargo:rustc-env=RUSTYTORCH_TARGET_ARCH={target_arch}");

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