use cc;

fn collect_c_files(dir: &str) -> Vec<std::path::PathBuf> {
    let mut files = vec![];
    for entry in std::fs::read_dir(dir).unwrap() {
        let path = entry.unwrap().path();
        if path.is_dir() {
            files.extend(collect_c_files(path.to_str().unwrap()));
        } else if path.extension().map_or(false, |e| e == "c") {
            files.push(path);
        }
    }
    files
}

fn main() {

  let cfiles = collect_c_files("../glc/src");

  cc::Build::new()
      .files(&cfiles)
      .compile("glc"); // produces libgl_layer.a

  let bindings = bindgen::Builder::default()
      .header("../glc/src/glc_api.h")
      .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
      .generate()
      .unwrap();

  bindings
      .write_to_file(std::path::PathBuf::from(std::env::var("OUT_DIR").unwrap()).join("bindings.rs"))
      .unwrap();

  let bindings_header = "../glc/src/glc_api.h";

  println!("cargo:rerun-if-changed=build.rs");
  println!("cargo:rerun-if-changed={bindings_header}");
  cfiles.iter().for_each(|c| {
    println!("cargo::rerun-if-changed={}", c.parent().unwrap().to_str().unwrap());
  });
}