use std::env;
use std::path::PathBuf;

fn main() {
    std::env::remove_var("NUM_JOBS");
    println!("cargo:rerun-if-changed=wrapper.h");

    let out = PathBuf::from(env::var("OUT_DIR").unwrap());

    // I'm tired of Cargo rebuilding GSL
    if !out.join("include/gsl").exists() {
        cmake::Config::new("./gsl")
            .define("NO_AMPL_BINDINGS", "1")
            .define("GSL_DISABLE_TESTS", "1")
            .always_configure(true)
            .profile("Release")
            .build();
    }

    let mut lib = out.clone();
    lib.push("lib");

    let mut headers1 = out.clone();
    headers1.push("include");

    let mut headers2 = out.clone();
    headers2.push("include/gsl");

    println!("cargo:rustc-link-search=native={}", lib.display());
    println!("cargo:rustc-link-lib=static=gsl");
    println!("cargo:rustc-link-lib=static=gslcblas");

    let bindings = bindgen::Builder::default()
        .header("wrapper.h")
        .clang_arg(format!("-I{}", headers1.display()))
        .clang_arg(format!("-I{}", headers2.display()))
        .blocklist_item("FP_.*")
        .blocklist_item(".*long_double.*")
        .allowlist_function("gsl.*")
        .allowlist_type("gsl.*")
        .allowlist_var("gsl.*")
        .allowlist_function("GSL.*")
        .allowlist_type("GSL.*")
        .allowlist_var("GSL.*")
        .generate()
        .expect("Unable to generate bindings");

    let out = PathBuf::from(std::env::var("OUT_DIR").unwrap());
    let out = out.join("bindings.rs");
    bindings
        .write_to_file(out)
        .expect("Couldn't write bindings!");
}