// Copyright 2018 Parity Technologies (UK) Ltd.
// This file is part of Substrate.

// Substrate 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.

// Substrate 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 Substrate.  If not, see <http://www.gnu.org/licenses/>.

//! Low-level types used throughout the Substrate code.

#![warn(missing_docs)]

#![cfg_attr(not(feature = "std"), no_std)]
#![cfg_attr(not(feature = "std"), feature(alloc))]

use runtime_primitives::generic;
use runtime_primitives::{OpaqueExtrinsic, traits::BlakeTwo256};

/// An index to a block.
pub type BlockNumber = u64;

/// Alias to Ed25519 pubkey that identifies an account on the chain. This will almost
/// certainly continue to be the same as the substrate's `AuthorityId`.
pub type AccountId = ::primitives::H256;

/// The type for looking up accounts. We don't expect more than 4 billion of them, but you
/// never know...
pub type AccountIndex = u32;

/// Balance of an account.
pub type Balance = u128;

/// The Ed25519 pub key of an session that belongs to an authority of the chain. This is
/// exactly equivalent to what the substrate calls an "authority".
pub type SessionKey = primitives::Ed25519AuthorityId;

/// Index of a transaction in the chain.
pub type Index = u64;

/// A hash of some data used by the chain.
pub type Hash = primitives::H256;

/// Alias to 512-bit hash when used in the context of a signature on the chain.
pub type Signature = runtime_primitives::Ed25519Signature;

/// A timestamp: seconds since the unix epoch.
pub type Timestamp = u64;

/// Header type.
pub type Header = generic::Header<BlockNumber, BlakeTwo256, generic::DigestItem<Hash, SessionKey>>;
/// Block type.
pub type Block = generic::Block<Header, UncheckedExtrinsic>;
/// Block ID.
pub type BlockId = generic::BlockId<Block>;

/// Opaque, encoded, unchecked extrinsic.
pub type UncheckedExtrinsic = OpaqueExtrinsic;
