/*
	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.

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

#pragma once

#include <thread>
#include <mutex>
#include "Common.h"
#include "BlockChain.h"
#include "TransactionQueue.h"
#include "State.h"
#include "Dagger.h"
#include "PeerNetwork.h"

namespace eth
{

struct MineProgress
{
	uint requirement;
	uint best;
	uint current;
};

class Client
{
public:
	/// Constructor.
	explicit Client(std::string const& _clientVersion, Address _us = Address(), std::string const& _dbPath = std::string());

	/// Destructor.
	~Client();

	/// Executes the given transaction.
	void transact(Secret _secret, Address _dest, u256 _amount, u256 _fee, u256s _data = u256s());

	/// Requires transactions involving this address be queued for inspection.
	void setInterest(Address _dest);

	/// @returns incoming minable transactions that we wanted to be notified of. Clears the queue.
	Transactions pendingQueue();

	/// @returns alterations in state of a mined block that we wanted to be notified of. Clears the queue.
	std::vector<std::pair<Address, AddressState>> minedQueue();

	// Not yet - probably best as using some sort of signals implementation.
	/// Calls @a _f when a valid transaction is received that involves @a _dest and once per such transaction.
//	void onPending(Address _dest, function<void(Transaction)> const& _f);

	/// Calls @a _f when a transaction is mined that involves @a _dest and once per change.
//	void onConfirmed(Address _dest, function<void(Transaction, AddressState)> const& _f);

	// Informational stuff:

	/// Locks/unlocks the state/blockChain/transactionQueue for access.
	void lock();
	void unlock();

	/// Determines whether at least one of the state/blockChain/transactionQueue has changed since the last call to changed().
	bool changed() const { auto ret = m_changed; m_changed = false; return ret; }

	/// Get the object representing the current state of Ethereum.
	State const& state() const { return m_s; }
	/// Get the object representing the current canonical blockchain.
	BlockChain const& blockChain() const { return m_bc; }
	/// Get the object representing the transaction queue.
	TransactionQueue const& transactionQueue() const { return m_tq; }

	// Network stuff:

	/// Get information on the current peer set.
	std::vector<PeerInfo> peers() { return m_net ? m_net->peers() : std::vector<PeerInfo>(); }
	/// Same as peers().size(), but more efficient.
	unsigned peerCount() const { return m_net ? m_net->peerCount() : 0; }

	/// Start the network subsystem.
	void startNetwork(short _listenPort = 30303, std::string const& _seedHost = std::string(), short _port = 30303, NodeMode _mode = NodeMode::Full, unsigned _peers = 5, std::string const& _publicIP = std::string(), bool _upnp = true);
	/// Connect to a particular peer.
	void connect(std::string const& _seedHost, short _port = 30303);
	/// Stop the network subsystem.
	void stopNetwork();

	// Mining stuff:

	/// Set the coinbase address.
	void setAddress(Address _us) { m_s.setAddress(_us); }
	/// Get the coinbase address.
	Address address() const { return m_s.address(); }
	/// Start mining.
	void startMining();
	/// Stop mining.
	void stopMining();
	/// Check the progress of the mining.
	MineProgress miningProgress() const { return m_mineProgress; }

private:
	void work();

	std::string m_clientVersion;		///< Our end-application client's name/version.
	BlockChain m_bc;					///< Maintains block database.
	TransactionQueue m_tq;				///< Maintains list of incoming transactions not yet on the block chain.
	Overlay m_stateDB;					///< Acts as the central point for the state database, so multiple States can share it.
	State m_s;							///< The present state of the client.
	PeerServer* m_net = nullptr;		///< Should run in background and send us events when blocks found and allow us to send blocks as required.
	std::thread* m_work;				///< The work thread.
	std::mutex m_lock;
	enum { Active = 0, Deleting, Deleted } m_workState = Active;
	bool m_doMine = false;				///< Are we supposed to be mining?
	MineProgress m_mineProgress;

	mutable bool m_changed;
};

}