/*
	This file is part of cpp-ethereum.

	cpp-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.

	cpp-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 cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
*/
/** @file CanonBlockChain.h
 * @author Gav Wood <i@gavwood.com>
 * @date 2014
 */

#pragma once

#include <mutex>
#include <libdevcore/Log.h>
#include <libdevcore/Exceptions.h>
#include <libethcore/Common.h>
#include <libethcore/BlockInfo.h>
#include <libdevcore/Guards.h>
#include "BlockDetails.h"
#include "Account.h"
#include "BlockChain.h"

namespace dev
{

namespace eth
{

// TODO: Move all this Genesis stuff into Genesis.h/.cpp
std::unordered_map<Address, Account> const& genesisState();

/**
 * @brief Implements the blockchain database. All data this gives is disk-backed.
 * @threadsafe
 * @todo Make not memory hog (should actually act as a cache and deallocate old entries).
 */
class CanonBlockChain: public BlockChain
{
public:
	CanonBlockChain(WithExisting _we = WithExisting::Trust, ProgressCallback const& _pc = ProgressCallback()): CanonBlockChain(std::string(), _we, _pc) {}
	CanonBlockChain(std::string const& _path, WithExisting _we = WithExisting::Trust, ProgressCallback const& _pc = ProgressCallback());
	~CanonBlockChain() {}

	/// @returns the genesis block header.
	static BlockInfo const& genesis();

	/// @returns the genesis block as its RLP-encoded byte array.
	/// @note This is slow as it's constructed anew each call. Consider genesis() instead.
	static bytes createGenesisBlock();

	/// Alter the value of the genesis block's nonce.
	/// @warning Unless you're very careful, make sure you call this right at the start of the
	/// program, before anything has had the chance to use this class at all.
	static void setGenesisNonce(Nonce const& _n);

private:
	/// Static genesis info and its lock.
	static boost::shared_mutex x_genesis;
	static std::unique_ptr<BlockInfo> s_genesis;
	static Nonce s_nonce;
};

}
}