#define LOG_MODULE PacketLogModuleRadiusLayer
#include "RadiusLayer.h"
#include "Logger.h"
#include "GeneralUtils.h"

#include <string.h>
#include <sstream>
#include "EndianPortable.h"

namespace pcpp
{

RadiusAttribute RadiusAttributeBuilder::build() const
{
	size_t recSize = m_RecValueLen+2;
	uint8_t* recordBuffer = new uint8_t[recSize];
	memset(recordBuffer, 0, recSize);
	recordBuffer[0] = static_cast<uint8_t>(m_RecType);
	recordBuffer[1] = static_cast<uint8_t>(recSize);
	if (m_RecValueLen > 0)
		memcpy(recordBuffer+2, m_RecValue, m_RecValueLen);

	return RadiusAttribute(recordBuffer);
}

RadiusLayer::RadiusLayer(uint8_t code, uint8_t id, const uint8_t* authenticator, uint8_t authenticatorArrSize)
{
	m_DataLen = sizeof(radius_header);
	m_Data = new uint8_t[m_DataLen];
	memset(m_Data, 0, m_DataLen);
	m_Protocol = Radius;

	radius_header* hdr = getRadiusHeader();
	hdr->code = code;
	hdr->id = id;
	hdr->length = htobe16(sizeof(radius_header));
	if (authenticatorArrSize == 0 || authenticator == nullptr)
		return;
	if (authenticatorArrSize > 16)
		authenticatorArrSize = 16;
	memcpy(hdr->authenticator, authenticator, authenticatorArrSize);
}

RadiusLayer::RadiusLayer(uint8_t code, uint8_t id, const std::string &authenticator)
{
	m_DataLen = sizeof(radius_header);
	m_Data = new uint8_t[m_DataLen];
	memset(m_Data, 0, m_DataLen);
	m_Protocol = Radius;

	radius_header* hdr = getRadiusHeader();
	hdr->code = code;
	hdr->id = id;
	hdr->length = htobe16(sizeof(radius_header));
	setAuthenticatorValue(authenticator);
}

RadiusAttribute RadiusLayer::addAttrAt(const RadiusAttributeBuilder& attrBuilder, int offset)
{
	RadiusAttribute newAttr = attrBuilder.build();
	if (newAttr.isNull())
	{
		PCPP_LOG_ERROR("Cannot build new attribute of type " << (int)newAttr.getType());
		return newAttr;
	}

	size_t sizeToExtend = newAttr.getTotalSize();
	if (!extendLayer(offset, sizeToExtend))
	{
		PCPP_LOG_ERROR("Could not extend RadiusLayer in [" << newAttr.getTotalSize() << "] bytes");
		newAttr.purgeRecordData();
		return RadiusAttribute(nullptr);
	}

	memcpy(m_Data + offset, newAttr.getRecordBasePtr(), newAttr.getTotalSize());

	uint8_t* newAttrPtr = m_Data + offset;

	m_AttributeReader.changeTLVRecordCount(1);

	newAttr.purgeRecordData();

	getRadiusHeader()->length = htobe16(m_DataLen);

	return RadiusAttribute(newAttrPtr);
}

std::string RadiusLayer::getAuthenticatorValue() const
{
	return byteArrayToHexString(getRadiusHeader()->authenticator, 16);
}

void RadiusLayer::setAuthenticatorValue(const std::string& authValue)
{
	hexStringToByteArray(authValue, getRadiusHeader()->authenticator, 16);
}

std::string RadiusLayer::getRadiusMessageString(uint8_t radiusMessageCode)
{
	switch (radiusMessageCode)
	{
	case 1:
		return "Access-Request";
	case 2:
		return "Access-Accept";
	case 3:
		return "Access-Reject";
	case 4:
		return "Accounting-Request";
	case 5:
		return "Accounting-Response";
	case 11:
		return "Access-Challenge";
	case 12:
		return "Status-Server";
	case 13:
		return "Status-Client";
	case 40:
		return "Disconnect-Request";
	case 41:
		return "Disconnect-ACK";
	case 42:
		return "Disconnect-NAK";
	case 43:
		return "CoA-Request";
	case 44:
		return "CoA-ACK";
	case 45:
		return "CoA-NAK";
	case 255:
		return "Reserved";
	default:
		return "Unknown";
	}
}

size_t RadiusLayer::getHeaderLen() const
{
	uint16_t len = be16toh(getRadiusHeader()->length);
	if (len > m_DataLen)
		return m_DataLen;

	return len;
}

void RadiusLayer::computeCalculateFields()
{
	getRadiusHeader()->length = htobe16(m_DataLen);
}

std::string RadiusLayer::toString() const
{
	std::ostringstream str;
	str << "RADIUS Layer, " <<
			RadiusLayer::getRadiusMessageString(getRadiusHeader()->code) <<
			"(" <<
			(int)getRadiusHeader()->code <<
			"), "
			"Id=" <<
			(int)getRadiusHeader()->id <<
			", " <<
			"Length=" <<
			be16toh(getRadiusHeader()->length);

	return str.str();
}

RadiusAttribute RadiusLayer::getFirstAttribute() const
{
	return m_AttributeReader.getFirstTLVRecord(getAttributesBasePtr(), getHeaderLen() - sizeof(radius_header));
}

RadiusAttribute RadiusLayer::getNextAttribute(RadiusAttribute& attr) const
{
	return m_AttributeReader.getNextTLVRecord(attr, getAttributesBasePtr(), getHeaderLen() - sizeof(radius_header));
}

RadiusAttribute RadiusLayer::getAttribute(uint8_t attributeType) const
{
	return m_AttributeReader.getTLVRecord(attributeType, getAttributesBasePtr(), getHeaderLen() - sizeof(radius_header));
}

size_t RadiusLayer::getAttributeCount() const
{
	return m_AttributeReader.getTLVRecordCount(getAttributesBasePtr(), getHeaderLen() - sizeof(radius_header));
}

RadiusAttribute RadiusLayer::addAttribute(const RadiusAttributeBuilder& attrBuilder)
{
	int offset = getHeaderLen();
	return addAttrAt(attrBuilder, offset);
}

RadiusAttribute RadiusLayer::addAttributeAfter(const RadiusAttributeBuilder& attrBuilder, uint8_t prevAttrType)
{
	int offset = 0;

	RadiusAttribute prevAttr = getAttribute(prevAttrType);

	if (prevAttr.isNull())
	{
		offset = getHeaderLen();
	}
	else
	{
		offset = prevAttr.getRecordBasePtr() + prevAttr.getTotalSize() - m_Data;
	}

	return addAttrAt(attrBuilder, offset);
}

bool RadiusLayer::removeAttribute(uint8_t attrType)
{
	RadiusAttribute attrToRemove = getAttribute(attrType);
	if (attrToRemove.isNull())
	{
		return false;
	}

	int offset = attrToRemove.getRecordBasePtr() - m_Data;

	if (!shortenLayer(offset, attrToRemove.getTotalSize()))
	{
		return false;
	}

	m_AttributeReader.changeTLVRecordCount(-1);
	getRadiusHeader()->length = htobe16(m_DataLen);

	return true;
}

bool RadiusLayer::removeAllAttributes()
{
	int offset = sizeof(radius_header);

	if (!shortenLayer(offset, getHeaderLen()-offset))
		return false;

	m_AttributeReader.changeTLVRecordCount(0-getAttributeCount());

	getRadiusHeader()->length = htobe16(m_DataLen);

	return true;
}

bool RadiusLayer::isDataValid(const uint8_t* udpData, size_t udpDataLen)
{
	if(udpData != nullptr && udpDataLen >= sizeof(radius_header))
	{
		const radius_header* radHdr = reinterpret_cast<const radius_header*>(udpData);
		size_t radLen = be16toh(radHdr->length);
		return radLen >= sizeof(radius_header) && radLen <= udpDataLen;
	}
	return false;
}

}