// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.

// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0

// This program is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

// This program is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License

// along with this program. If not, see <https://www.gnu.org/licenses/>.

use futures::{

	future::{self, BoxFuture, FutureExt},

	pin_mut, select, Future,

};

use sc_service::Error as ServiceError;

/// Abstraction over OS signals to handle the shutdown of the node smoothly.

///

/// On `unix` this represents `SigInt` and `SigTerm`.

pub struct Signals(BoxFuture<'static, ()>);

impl Signals {

	/// Return the signals future.

	/// Capture the relevant signals to handle shutdown of the node smoothly.

	///

	/// Needs to be called in a Tokio context to have access to the tokio reactor.

	#[cfg(target_family = "unix")]

		use tokio::signal::unix::{signal, SignalKind};

	/// Capture the relevant signals to handle shutdown of the node smoothly.

	///

	/// Needs to be called in a Tokio context to have access to the tokio reactor.

	#[cfg(not(unix))]

	pub fn capture() -> Result<Self, ServiceError> {

		use tokio::signal::ctrl_c;

		Ok(Signals(

			async move {

				let _ = ctrl_c().await;

			}

			.boxed(),

		))

	}

	/// A dummy signal that never returns.

	/// Run a future task until receive a signal.

		}

}