// 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/>.

//! Client extension for tests.

use client::{self, Client};
use consensus::{ImportBlock, BlockImport, BlockOrigin};
use runtime_primitives::generic::BlockId;
use primitives::Blake2Hasher;
use runtime;

/// Extension trait for a test client.
pub trait TestClient: Sized {
	/// Justify and import block to the chain. No finality.
	fn justify_and_import(&self, origin: BlockOrigin, block: runtime::Block)
		-> client::error::Result<()>;

	/// Finalize a block.
	fn finalize_block(&self, id: BlockId<runtime::Block>) -> client::error::Result<()>;

	/// Returns hash of the genesis block.
	fn genesis_hash(&self) -> runtime::Hash;
}

impl<B, E> TestClient for Client<B, E, runtime::Block>
	where
		B: client::backend::Backend<runtime::Block, Blake2Hasher>,
		E: client::CallExecutor<runtime::Block, Blake2Hasher>,
		Self: BlockImport<runtime::Block, Error=client::error::Error>
{
	fn justify_and_import(&self, origin: BlockOrigin, block: runtime::Block)
		-> client::error::Result<()>
	{
		let import = ImportBlock {
			origin,
			header: block.header,
			external_justification: vec![],
			post_runtime_digests: vec![],
			body: Some(block.extrinsics),
			finalized: false,
			auxiliary: Vec::new(),
		};

		self.import_block(import, None).map(|_| ())
	}

	fn finalize_block(&self, id: BlockId<runtime::Block>) -> client::error::Result<()> {
		self.finalize_block(id, true)
	}

	fn genesis_hash(&self) -> runtime::Hash {
		self.block_hash(0).unwrap().unwrap()
	}
}