use std::path::PathBuf;

fn main() {
    let ld = std::path::Path::new("linker.ld").canonicalize().unwrap();
    println!("cargo:rustc-link-arg=-T{}", ld.display());
    println!("cargo:rerun-if-changed=linker.ld");

    // Init and storage are packed into the kernel image: they are what
    // reads the disk, so they cannot come from it. `make build` builds them
    // first; without them the image boots to "init missing".
    let manifest = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
    let bins = manifest.join("../../target/riscv64gc-unknown-none-elf/release");
    let out = PathBuf::from(std::env::var("OUT_DIR").unwrap());
    for (var, bin) in [("KOS_INIT_ELF", "init"), ("KOS_STORAGE_ELF", "storage-qemu")] {
        let path = bins.join(bin);
        println!("cargo:rerun-if-changed={}", path.display());
        let path = if path.is_file() {
            path
        } else {
            let empty = out.join(bin);
            std::fs::write(&empty, []).unwrap();
            empty
        };
        println!("cargo:rustc-env={}={}", var, path.display());
    }
}