// Copyright 2019-2020 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/>.

//! Millau-to-Rialto headers sync entrypoint.

use crate::{
	headers_pipeline::SubstrateHeadersToSubstrate, headers_target::SubstrateHeadersSyncPipeline, MillauClient,
	RialtoClient,
};

use async_trait::async_trait;
use bp_millau::{
	BEST_MILLAU_BLOCKS_METHOD, FINALIZED_MILLAU_BLOCK_METHOD, INCOMPLETE_MILLAU_HEADERS_METHOD,
	IS_KNOWN_MILLAU_BLOCK_METHOD,
};
use headers_relay::sync_types::QueuedHeader;
use relay_millau_client::{HeaderId as MillauHeaderId, Millau, SyncHeader as MillauSyncHeader};
use relay_rialto_client::{BridgeMillauCall, Rialto, SigningParams as RialtoSigningParams};
use relay_substrate_client::{Error as SubstrateError, TransactionSignScheme};
use sp_core::Pair;
use sp_runtime::Justification;

/// Millau-to-Rialto headers sync pipeline.
pub(crate) type MillauHeadersToRialto =
	SubstrateHeadersToSubstrate<Millau, MillauSyncHeader, Rialto, RialtoSigningParams>;
/// Millau header in-the-queue.
type QueuedMillauHeader = QueuedHeader<MillauHeadersToRialto>;

#[async_trait]
impl SubstrateHeadersSyncPipeline for MillauHeadersToRialto {
	const BEST_BLOCK_METHOD: &'static str = BEST_MILLAU_BLOCKS_METHOD;
	const FINALIZED_BLOCK_METHOD: &'static str = FINALIZED_MILLAU_BLOCK_METHOD;
	const IS_KNOWN_BLOCK_METHOD: &'static str = IS_KNOWN_MILLAU_BLOCK_METHOD;
	const INCOMPLETE_HEADERS_METHOD: &'static str = INCOMPLETE_MILLAU_HEADERS_METHOD;

	type SignedTransaction = <Rialto as TransactionSignScheme>::SignedTransaction;

	async fn make_submit_header_transaction(
		&self,
		header: QueuedMillauHeader,
	) -> Result<Self::SignedTransaction, SubstrateError> {
		let account_id = self.target_sign.signer.public().as_array_ref().clone().into();
		let nonce = self.target_client.next_account_index(account_id).await?;
		let call = BridgeMillauCall::import_signed_header(header.header().clone().into()).into();
		let transaction = Rialto::sign_transaction(&self.target_client, &self.target_sign.signer, nonce, call);
		Ok(transaction)
	}

	async fn make_complete_header_transaction(
		&self,
		id: MillauHeaderId,
		completion: Justification,
	) -> Result<Self::SignedTransaction, SubstrateError> {
		let account_id = self.target_sign.signer.public().as_array_ref().clone().into();
		let nonce = self.target_client.next_account_index(account_id).await?;
		let call = BridgeMillauCall::finalize_header(id.1, completion).into();
		let transaction = Rialto::sign_transaction(&self.target_client, &self.target_sign.signer, nonce, call);
		Ok(transaction)
	}
}

/// Run Millau-to-Rialto headers sync.
pub async fn run(
	millau_client: MillauClient,
	rialto_client: RialtoClient,
	rialto_sign: RialtoSigningParams,
	metrics_params: Option<relay_utils::metrics::MetricsParams>,
) {
	crate::headers_pipeline::run(
		MillauHeadersToRialto::new(rialto_client.clone(), rialto_sign),
		millau_client,
		rialto_client,
		metrics_params,
	)
	.await;
}