/*
	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 Common.h
 * @author Gav Wood <i@gavwood.com>
 * @date 2014
 *
 * Miscellanea required for the PeerHost/PeerSession classes.
 */

#pragma once

#include <string>
#include <boost/asio.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <chrono>
#include <libethential/Common.h>
#include <libethential/Log.h>
namespace ba = boost::asio;
namespace bi = boost::asio::ip;

namespace eth
{

bool isPrivateAddress(bi::address _addressToCheck);

class RLP;
class RLPStream;
class PeerHost;
class PeerSession;

struct NetWarn: public LogChannel { static const char* name() { return "!N!"; } static const int verbosity = 0; };
struct NetNote: public LogChannel { static const char* name() { return "*N*"; } static const int verbosity = 1; };
struct NetMessageSummary: public LogChannel { static const char* name() { return "-N-"; } static const int verbosity = 2; };
struct NetConnect: public LogChannel { static const char* name() { return "+N+"; } static const int verbosity = 4; };
struct NetMessageDetail: public LogChannel { static const char* name() { return "=N="; } static const int verbosity = 5; };
struct NetTriviaSummary: public LogChannel { static const char* name() { return "-N-"; } static const int verbosity = 10; };
struct NetTriviaDetail: public LogChannel { static const char* name() { return "=N="; } static const int verbosity = 11; };
struct NetAllDetail: public LogChannel { static const char* name() { return "=N="; } static const int verbosity = 13; };
struct NetRight: public LogChannel { static const char* name() { return ">N>"; } static const int verbosity = 14; };
struct NetLeft: public LogChannel { static const char* name() { return "<N<"; } static const int verbosity = 15; };

enum PacketType
{
	HelloPacket = 0,
	DisconnectPacket,
	PingPacket,
	PongPacket,
	GetPeersPacket,
	PeersPacket,
	UserPacket = 0x10
};

enum DisconnectReason
{
	DisconnectRequested = 0,
	TCPError,
	BadProtocol,
	UselessPeer,
	TooManyPeers,
	DuplicatePeer,
	IncompatibleProtocol,
	InvalidIdentity,
	ClientQuit,
	UserReason = 0x10
};

/// @returns the string form of the given disconnection reason.
std::string reasonOf(DisconnectReason _r);

struct PeerInfo
{
	std::string clientVersion;
	std::string host;
	unsigned short port;
	std::chrono::steady_clock::duration lastPing;
};

class UPnP;

class PeerCapability;

class HostCapabilityFace
{
	friend class PeerHost;
	template <class T> friend class HostCapability;
	friend class PeerCapability;

public:
	HostCapabilityFace() {}
	virtual ~HostCapabilityFace() {}

	PeerHost* host() const { return m_host; }

	std::vector<std::shared_ptr<PeerSession> > peers() const;

protected:
	virtual std::string name() const = 0;
	virtual PeerCapability* newPeerCapability(PeerSession* _s) = 0;
	virtual bool isInitialised() const = 0;

	void seal(bytes& _b);

private:
	PeerHost* m_host = nullptr;
};

template<class PeerCap>
class HostCapability: public HostCapabilityFace
{
public:
	HostCapability() {}
	virtual ~HostCapability() {}

	static std::string staticName() { return PeerCap::name(); }

protected:
	virtual bool isInitialised() const = 0;
	virtual std::string name() const { return PeerCap::name(); }
	virtual PeerCapability* newPeerCapability(PeerSession* _s) { return new PeerCap(_s, this); }
};

class PeerCapability
{
	friend class PeerSession;

public:
	PeerCapability(PeerSession* _s, HostCapabilityFace* _h): m_session(_s), m_host(_h) {}
	virtual ~PeerCapability() {}

	/// Must return the capability name.
	static std::string name() { return ""; }

	PeerSession* session() const { return m_session; }
	HostCapabilityFace* hostCapability() const { return m_host; }

protected:
	virtual bool interpret(RLP const&) = 0;

	void disable(std::string const& _problem);

	static RLPStream& prep(RLPStream& _s);
	void sealAndSend(RLPStream& _s);
	void sendDestroy(bytes& _msg);
	void send(bytesConstRef _msg);

	void addRating(unsigned _r);

private:
	PeerSession* m_session;
	HostCapabilityFace* m_host;
	bool m_enabled = true;
};

}