extern crate bindgen;

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

fn main() {
    // Tell cargo to invalidate the built crate whenever the wrapper changes
    println!("cargo:rerun-if-changed=wrapper.h");

    // The bindgen::Builder is the main entry point
    // to bindgen, and lets you build up options for
    // the resulting bindings.
    let bindings = bindgen::Builder::default()
        // The input header we would like to generate
        // bindings for.
        .header("wrapper.h")
        // Tell cargo to invalidate the built crate whenever any of the
        // included header files changed.
        .parse_callbacks(Box::new(bindgen::CargoCallbacks))
        // Finish the builder and generate the bindings.
        .generate()
        // Unwrap the Result and panic on failure.
        .expect("Unable to generate bindings");

    // Write the bindings to the src/bindings/[os]/[arch]/bindings.rs file.
    let out_path = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap())
        .join("src")
        .join("bindings")
        .join(env::var("CARGO_CFG_TARGET_OS").unwrap())
        .join(env::var("CARGO_CFG_TARGET_ARCH").unwrap());

    // If the directory doesn't exist, create it
    fs::create_dir_all(&out_path).expect("Unable to create dir");

    // Write bindings to file
    bindings
        .write_to_file(out_path.join("bindings.rs"))
        .expect("Couldn't write bindings!");
}