// Copyright 2019-2021 Parity Technologies (UK) Ltd.
// This file is part of Parity Bridges Common.

// Parity Bridges Common 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.

// Parity Bridges Common 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 Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.

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

use bp_message_lane::MessageNonce;
use bp_runtime::Chain;
use frame_support::RuntimeDebug;
use sp_core::Hasher as HasherT;
use sp_runtime::{
	generic,
	traits::{BlakeTwo256, IdentifyAccount, Verify},
	MultiSignature, OpaqueExtrinsic as UncheckedExtrinsic,
};

// Re-export's to avoid extra substrate dependencies in chain-specific crates.
pub use frame_support::Parameter;
pub use sp_runtime::traits::Convert;

// TODO [#78] may need to be updated after https://github.com/paritytech/parity-bridges-common/issues/78
/// Maximal number of messages in single delivery transaction.
pub const MAX_MESSAGES_IN_DELIVERY_TRANSACTION: MessageNonce = 128;

/// Maximal number of unrewarded relayer entries at inbound lane.
pub const MAX_UNREWARDED_RELAYER_ENTRIES_AT_INBOUND_LANE: MessageNonce = 128;

// TODO [#438] should be selected keeping in mind:
// finality delay on both chains + reward payout cost + messages throughput.
/// Maximal number of unconfirmed messages at inbound lane.
pub const MAX_UNCONFIRMED_MESSAGES_AT_INBOUND_LANE: MessageNonce = 8192;

/// Block number type used in Polkadot-like chains.
pub type BlockNumber = u32;

/// Hash type used in Polkadot-like chains.
pub type Hash = <BlakeTwo256 as HasherT>::Out;

/// The type of an object that can produce hashes on Polkadot-like chains.
pub type Hasher = BlakeTwo256;

/// The header type used by Polkadot-like chains.
pub type Header = generic::Header<BlockNumber, Hasher>;

/// Signature type used by Polkadot-like chains.
pub type Signature = MultiSignature;

/// Public key of account on Polkadot-like chains.
pub type AccountPublic = <Signature as Verify>::Signer;

/// Id of account on Polkadot-like chains.
pub type AccountId = <AccountPublic as IdentifyAccount>::AccountId;

/// Index of a transaction on the Polkadot-like chains.
pub type Nonce = u32;

/// Block type of Polkadot-like chains.
pub type Block = generic::Block<Header, UncheckedExtrinsic>;

/// Polkadot-like block signed with a Justification.
pub type SignedBlock = generic::SignedBlock<Block>;

/// The balance of an account on Polkadot-like chain.
pub type Balance = u128;

/// Polkadot-like chain.
#[derive(RuntimeDebug)]
pub struct PolkadotLike;

impl Chain for PolkadotLike {
	type BlockNumber = BlockNumber;
	type Hash = Hash;
	type Hasher = Hasher;
	type Header = Header;
}

/// Convert a 256-bit hash into an AccountId.
pub struct AccountIdConverter;

impl Convert<sp_core::H256, AccountId> for AccountIdConverter {
	fn convert(hash: sp_core::H256) -> AccountId {
		hash.to_fixed_bytes().into()
	}
}