// Copyright 2015-2019 Parity Technologies (UK) Ltd.
// This file is part of Parity Ethereum.

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

//! Private transaction signing RPC implementation.

use std::sync::Arc;

use rlp::Rlp;

use ethcore_private_tx::Provider as PrivateTransactionManager;
use ethereum_types::{Address, H160, H256, U256};
use types::transaction::SignedTransaction;

use jsonrpc_core::{Error};
use v1::types::{Bytes, PrivateTransactionReceipt, TransactionRequest,
	BlockNumber, PrivateTransactionReceiptAndTransaction, CallRequest, block_number_to_id};
use v1::traits::Private;
use v1::metadata::Metadata;
use v1::helpers::{errors, fake_sign};

/// Private transaction manager API endpoint implementation.
pub struct PrivateClient {
	private: Option<Arc<PrivateTransactionManager>>,
}

impl PrivateClient {
	/// Creates a new instance.
	pub fn new(private: Option<Arc<PrivateTransactionManager>>) -> Self {
		PrivateClient {
			private,
		}
	}

	fn unwrap_manager(&self) -> Result<&PrivateTransactionManager, Error> {
		match self.private {
			Some(ref arc) => Ok(&**arc),
			None => Err(errors::light_unimplemented(None)),
		}
	}
}

impl Private for PrivateClient {
	type Metadata = Metadata;

	fn send_transaction(&self, request: Bytes) -> Result<PrivateTransactionReceipt, Error> {
		let signed_transaction = Rlp::new(&request.into_vec()).as_val()
			.map_err(errors::rlp)
			.and_then(|tx| SignedTransaction::new(tx).map_err(errors::transaction))?;
		let client = self.unwrap_manager()?;
		let receipt = client.create_private_transaction(signed_transaction).map_err(errors::private_message)?;
		Ok(receipt.into())
	}

	fn compose_deployment_transaction(&self, block_number: BlockNumber, request: Bytes, validators: Vec<H160>, gas_price: U256) -> Result<PrivateTransactionReceiptAndTransaction, Error> {
		let signed_transaction = Rlp::new(&request.into_vec()).as_val()
			.map_err(errors::rlp)
			.and_then(|tx| SignedTransaction::new(tx).map_err(errors::transaction))?;
		let client = self.unwrap_manager()?;

		let addresses: Vec<Address> = validators.into_iter().map(Into::into).collect();
		let id = match block_number {
			BlockNumber::Pending => return Err(errors::private_message_block_id_not_supported()),
			num => block_number_to_id(num)
		};

		let (transaction, contract_address) = client
			.public_creation_transaction(id, &signed_transaction, addresses.as_slice(), gas_price)
			.map_err(errors::private_message)?;
		let tx_hash = transaction.hash(None);
		let request = TransactionRequest {
			from: Some(signed_transaction.sender()),
			to: None,
			nonce: Some(transaction.nonce),
			gas_price: Some(transaction.gas_price),
			gas: Some(transaction.gas),
			value: Some(transaction.value),
			data: Some(transaction.data.into()),
			condition: None,
		};

		Ok(PrivateTransactionReceiptAndTransaction {
			transaction: request,
			receipt: PrivateTransactionReceipt {
				transaction_hash: tx_hash,
				contract_address,
				status_code: 0,
			}
		})
	}

	fn private_call(&self, block_number: BlockNumber, request: CallRequest) -> Result<Bytes, Error> {
		let id = match block_number {
			BlockNumber::Pending => return Err(errors::private_message_block_id_not_supported()),
			num => block_number_to_id(num)
		};

		let request = CallRequest::into(request);
		let signed = fake_sign::sign_call(request)?;
		let client = self.unwrap_manager()?;
		let executed_result = client.private_call(id, &signed).map_err(errors::private_message)?;
		Ok(executed_result.output.into())
	}

	fn private_contract_key(&self, contract_address: H160) -> Result<H256, Error> {
		let client = self.unwrap_manager()?;
		let key = client.contract_key_id(&contract_address).map_err(errors::private_message)?;
		Ok(key)
	}
}