/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

use gl_generator::{Api, Fallbacks, Profile, Registry};
use std::env;
use std::fs::File;
use std::path::Path;

fn main() {
    let target = env::var("TARGET").unwrap();
    if target.contains("android") {
        android_main()
    }
    generate_gl_bindings(&target);
}

fn android_main() {
    // Get the NDK path from NDK_HOME env.
    let ndk_path =
        env::var_os("ANDROID_NDK").expect("Please set the ANDROID_NDK environment variable");
    let ndk_path = Path::new(&ndk_path);

    // compiling android_native_app_glue.c
    let c_file = ndk_path
        .join("sources")
        .join("android")
        .join("native_app_glue")
        .join("android_native_app_glue.c");
    cc::Build::new()
        .file(c_file)
        .warnings(false)
        .compile("android_native_app_glue");

    // Get the output directory.
    let out_dir =
        env::var("OUT_DIR").expect("Cargo should have set the OUT_DIR environment variable");

    println!("cargo:rustc-link-lib=static=android_native_app_glue");
    println!("cargo:rustc-link-search=native={}", out_dir);
    println!("cargo:rustc-link-lib=log");
    println!("cargo:rustc-link-lib=android");
}

fn generate_gl_bindings(target: &str) {
    // For now, we only support EGL, and only on Windows and Android.
    if target.contains("android") || target.contains("windows") {
        let dest = env::var("OUT_DIR").unwrap();
        let mut file = File::create(&Path::new(&dest).join("egl_bindings.rs")).unwrap();
        if target.contains("android") {
            Registry::new(Api::Egl, (1, 5), Profile::Core, Fallbacks::All, [])
                .write_bindings(gl_generator::StaticStructGenerator, &mut file)
                .unwrap();
        }
        if target.contains("windows") {
            Registry::new(Api::Egl, (1, 5), Profile::Core, Fallbacks::All, [])
                .write_bindings(gl_generator::StructGenerator, &mut file)
                .unwrap();
        };
    }
}