use std::sync::Arc;
use tokio::sync::Mutex;

use crate::{Error, Result};

pub struct NetworkLeash {
    lock: Arc<Mutex<()>>
}

impl NetworkLeash {
    pub fn new() -> Self {
        tracing::trace!("Creating new NetworkLeash");
        Self {
            lock: Arc::new(Mutex::new(())),
        }
    }

    pub async fn with_interface<F, R>(&self, name: &str, operation: F) -> Result<R>
    where
        F: FnOnce(&mut ifconfig::Iface) -> Result<R> + Send + 'static,
        R: Send + 'static,
    {
        let _guard = self.lock.lock().await;
        let name = name.to_string();

        tokio::task::spawn_blocking(move || {
            let mut iface = ifconfig::Iface::new(&name)?;
            operation(&mut iface)
        }).await?
    }

    pub async fn gated<F, R>(&self, operation: F) -> Result<R>
    where
        F: FnOnce() -> Result<R> + Send + 'static,
        R: Send + 'static,
    {
        let _guard = self.lock.lock().await;

        tokio::task::spawn_blocking(move || {
            operation()
        }).await?
    }
}