// Copyright 2018 Parity Technologies (UK) Ltd.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

//! Implementation of the libp2p-specific Kademlia protocol.

// TODO: we allow dead_code for now because this library contains a lot of unused code that will
//       be useful later for record store
#![allow(dead_code)]

pub mod handler;
pub mod kbucket;
pub mod protocol;
pub mod record;

mod addresses;
mod behaviour;
mod jobs;
mod query;

mod dht_proto {
    include!(concat!(env!("OUT_DIR"), "/dht.pb.rs"));
}

pub use addresses::Addresses;
pub use behaviour::{Kademlia, KademliaConfig, KademliaEvent, Quorum};
pub use behaviour::{
    BootstrapResult,
    BootstrapOk,
    BootstrapError,

    GetRecordResult,
    GetRecordOk,
    GetRecordError,

    PutRecordResult,
    PutRecordOk,
    PutRecordError,

    GetClosestPeersResult,
    GetClosestPeersOk,
    GetClosestPeersError,

    AddProviderResult,
    AddProviderOk,
    AddProviderError,

    GetProvidersResult,
    GetProvidersOk,
    GetProvidersError,
};
pub use query::QueryId;
pub use protocol::KadConnectionType;
pub use record::{store, Record, ProviderRecord};

use std::num::NonZeroUsize;

/// The `k` parameter of the Kademlia specification.
///
/// This parameter determines:
///
///   1) The (fixed) maximum number of nodes in a bucket.
///   2) The (default) replication factor, which in turn determines:
///       a) The number of closer peers returned in response to a request.
///       b) The number of closest peers to a key to search for in an iterative query.
///
/// The choice of (1) is fixed to this constant. The replication factor is configurable
/// but should generally be no greater than `K_VALUE`. All nodes in a Kademlia
/// DHT should agree on the choices made for (1) and (2).
///
/// The current value is `20`.
pub const K_VALUE: NonZeroUsize = unsafe { NonZeroUsize::new_unchecked(20) };

/// The `α` parameter of the Kademlia specification.
///
/// This parameter determines the default parallelism for iterative queries,
/// i.e. the allowed number of in-flight requests that an iterative query is
/// waiting for at a particular time while it continues to make progress towards
/// locating the closest peers to a key.
///
/// The current value is `3`.
pub const ALPHA_VALUE: NonZeroUsize = unsafe { NonZeroUsize::new_unchecked(3) };