/* 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 std::cmp::Ord;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::sync::{LazyLock, Mutex};
use std::thread;

use tokio::runtime::{Builder, Runtime};

pub static HANDLE: LazyLock<Mutex<Option<Runtime>>> = LazyLock::new(|| {
    Mutex::new(Some(
        Builder::new_multi_thread()
            .thread_name_fn(|| {
                static ATOMIC_ID: AtomicUsize = AtomicUsize::new(0);
                let id = ATOMIC_ID.fetch_add(1, Ordering::Relaxed);
                format!("tokio-runtime-{}", id)
            })
            .worker_threads(
                thread::available_parallelism()
                    .map(|i| i.get())
                    .unwrap_or(servo_config::pref!(threadpools_fallback_worker_num) as usize)
                    .min(
                        servo_config::pref!(threadpools_async_runtime_workers_max).max(1) as usize,
                    ),
            )
            .enable_io()
            .enable_time()
            .build()
            .unwrap(),
    ))
});