#include <guitar/license.hpp>
#include <guitar/uutool.hpp>
#include <common/block.hpp>
#include <common/versioninfo.hpp>

/*
  The license will be uuencoded on top of xor.  This should be sufficient to protect the contents.
  Lic:  TM105R20020101013001EF
	      VVVVVVYYYYMMDDTTDDCCCC

				XX=version TM105R.  should check this against this product version and release
				YYYY=year of license issuance.  30 day license will use this value to expire itself.
				MM=month of license issuance    30 day license will use this value to expiure
				DD=day of license issuance
				TT=type of license
				   01=30 day license, expires 30 days from issuance.
					 02=Full license, never expires.
				DD=for type 01 license, indicates number of days license is good for.
				CCCC=checksum, just add up ASCII values of the characters through TT, display in hex.
*/

const String License::smBeginLicense="BEGIN LICENSE";
const String License::smEndLicense="END LICENSE";

String License::generate(const String &strProductVersion,const SystemTime &issueDate,LicenseType licenseType,int dayCount)
{
  String strLicenseKey;
	String strIssueDate;
	String strLicenseType;
	String strDayCount;
	String strChecksum;

  strLicenseKey=String("TM");
	strLicenseKey+=strProductVersion.substr(0,3);
	::sprintf(strIssueDate,"%4d%02d%02d",issueDate.year(),issueDate.month(),issueDate.day());
	strLicenseKey+=strIssueDate;
	::sprintf(strLicenseType,"%02d",licenseType);
	strLicenseKey+=strLicenseType;
	::sprintf(strDayCount,"%02d",dayCount);
  strLicenseKey+=strDayCount;
	::sprintf(strChecksum,"%04lx",calculateChecksum(strLicenseKey));
	strLicenseKey+=strChecksum;
	return UUTool::encode(xor(strLicenseKey));
}

String numericEncode(const String &strLicense)
{
  return String();
}

String numericDecode(const String &strLicense)
{
  return String();
}

bool License::fromLines(Block<String> &strLicenseLines)
{
  if(3!=strLicenseLines.size())return false;
	if(!(strLicenseLines[0]==smBeginLicense))return false;
	if(!(strLicenseLines[2]==smEndLicense))return false;
	return fromString(strLicenseLines[1]);
}

// TM105R2002040301 30 03d8

bool License::fromString(const String &strLicense)
{
	VersionInfo versionInfo;
	SystemTime currDate;
	SystemTime expireDate;
  String strHeader;
	String strDecoded;
 	String strVersion;
	int hashCode;

  mUUEncodedLicense=strLicense;
  strDecoded=xor(UUTool::decode(strLicense));
	strHeader=strDecoded.substr(0,1);
	if(!(strHeader==String("TM")))return false;
	mProductVersion=strDecoded.substr(2,5);
	mIssueDate.year(strDecoded.substr(6,9).toInt());
	mIssueDate.month((SystemTime::Month)strDecoded.substr(10,11).toInt());
	mIssueDate.day(strDecoded.substr(12,13).toInt());
	mLicenseType=(LicenseType)strDecoded.substr(14,15).toInt();
	mDayCount=strDecoded.substr(16,17).toInt();
	hashCode=strDecoded.substr(18,21).hex();
	if(hashCode!=calculateChecksum(strDecoded.substr(0,17)))return false;
	strVersion=versionInfo.getProductVersionString();
	strVersion.removeTokens(", ");
	strVersion.upper();
	if(!(strVersion==mProductVersion))return false;
	if(Permanent==mLicenseType)return mIsValid=true;
	expireDate=mIssueDate;
	expireDate.daysAdd360(mDayCount);
	if(currDate>=expireDate)return false;
	return mIsValid=true;
}

String License::xor(const String &strLicense)
{
  String strEncoded;
	int strLength;

	strEncoded.reserve((strLength=strLicense.length())+1);
	for(int index=0;index<strLength;index++)strEncoded.setAt(index,strLicense.charAt(index)^XORMagic);
	return strEncoded;
}

int License::calculateChecksum(const String &string)
{
	int stringLength=string.length();
  int sum=0;

	for(int index=0;index<stringLength;index++)sum+=string[index];
	return sum;
}