#include "StdAfx.h"
#include ".\eanbarcode.h"

//	binary representation of numbers in EAN
char* szEANs [10] = {"0001101", "0011001", "0010011", "0111101", "0100011",
		"0110001", "0101111", "0111011", "0110111", "0001011"};

CEANBarCode::CEANBarCode(void)
{
	memset(m_szCode, '\0', 14);

	//	This is an initial value, could be anything, product i mean.
	SetCode("7501031311309");
}

CEANBarCode::~CEANBarCode(void)
{
}

void CEANBarCode::SetCode(CString Code)
{
	//	this for making sure that the code is 13 length.
	while(Code.GetLength()<13)
		Code.Insert(0,'0');

	strcpy(m_szCode, Code.GetBuffer());
	Code.ReleaseBuffer();
}

CString CEANBarCode::GetCode()
{
	CString Code;

	Code = m_szCode;

	return Code;
}

////////////////////////////////////////
//	Check the validity of a the code  //
////////////////////////////////////////
bool CEANBarCode::CheckCode()
{
	int Sum = 0;
	for(int i=2;i<=12;i+=2)
		Sum += GetAt(i) * 3;
	for(int i=1;i<=12;i+=2)
		Sum += GetAt(i);
	if(10-(Sum%10)==GetAt(13))
		return true;
	return false;
}

//////////////////////////////////////////////////////////////////////////
//	Get a Number in the code by its position, starting from the left    //
//////////////////////////////////////////////////////////////////////////
int CEANBarCode::GetAt(int Position)
{
	char c[2];
	c[0] = m_szCode[Position-1];
	c[1] = '\0';
	return atoi(c);
}

////////////////////////////////////////////////////////////////////////////////////////
//	Gets the binary string representing the left part of the code when even parity    //
////////////////////////////////////////////////////////////////////////////////////////
CString CEANBarCode::GetLeftEven(int Digit)
{
	CString sBuffer;
	sBuffer = GetRight(Digit);
	ReverseString(sBuffer);
	return sBuffer;
}

///////////////////////////////////////////////////////////////////////
//	Gets the binary string representing the right part of the code   //
///////////////////////////////////////////////////////////////////////
CString CEANBarCode::GetRight(int Digit)
{
	CString sBuffer;
	sBuffer = GetLeftOdd(Digit);
	for(int i=0;i<7;i++)
	{
		if(sBuffer[i]=='0')
			sBuffer.SetAt(i, '1');
		else
			sBuffer.SetAt(i, '0');
	}
	return sBuffer;
}
//////////////////////////////////////////////////////////////////////////////////////
//	Gets the binary string representing the left part of the code when odd parity   //
//////////////////////////////////////////////////////////////////////////////////////
CString CEANBarCode::GetLeftOdd(int Digit)
{
	CString sBuffer;

	// gets the digit binary representation from the static array szEANs
	sBuffer = szEANs[Digit];
	return sBuffer;
}

///////////////////////////////////////////////////////////////
//	Draws the code using the specified DC and the rectangle  //
///////////////////////////////////////////////////////////////
void CEANBarCode::Draw(CPaintDC &dc)
{
	int PenWidth = 2;
	CBrush BlackBrush(RGB(0,0,0));
	CBrush WhiteBrush(RGB(255,255,255));
	char N[2];
	CString sBuffer;
	int X, i, x, y, j;
	RECT Rect;

	if(!CheckCode())
	{
		CString str;
		str = "Invalid Code";
		dc.TextOut(50, 50, str);
		return;
	}

	X = 10;

	//	draw odd
	Rect.top=20;
	Rect.bottom=120;
	Rect.left=X;
	Rect.right=X+PenWidth;

	memset(N,'\0',2);
	N[0] = GetAt(1)+'0';

	dc.TextOut(X-10,Rect.bottom-Rect.top,N,1);

	dc.FillRect(&Rect,&BlackBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&WhiteBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&BlackBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	for(i=2;i<=7;i++)
	{
		Rect.bottom=100;

		memset(N,'\0',2);
		N[0] = GetAt(i)+'0';

		x = Rect.left+PenWidth*4;
		y = Rect.bottom+10;

		dc.TextOut(x,y,N,1);

		if(i%2==0)
			sBuffer = GetLeftOdd(GetAt(i));
		else
			sBuffer = GetLeftEven(GetAt(i));

		for(j=0;j<7;j++)
		{
			if(sBuffer[j]=='1')
				dc.FillRect(&Rect,&BlackBrush);
			else
				dc.FillRect(&Rect,&WhiteBrush);
			Rect.left+=PenWidth;
			Rect.right+=PenWidth;
		}
	}
	Rect.bottom=120;

	dc.FillRect(&Rect,&WhiteBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&BlackBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&WhiteBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&BlackBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&WhiteBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	for(i=8;i<=13;i++)
	{
		Rect.bottom=100;

		memset(N,'\0',2);
		N[0] = GetAt(i)+'0';
		
		x = Rect.left;
		y = Rect.bottom+10;

		dc.TextOut(x,y,N,1);

		sBuffer = GetRight(GetAt(i));

		for(j=0;j<7;j++)
		{
			if(sBuffer[j]=='1')
				dc.FillRect(&Rect,&BlackBrush);
			else
				dc.FillRect(&Rect,&WhiteBrush);
			Rect.left+=PenWidth;
			Rect.right+=PenWidth;
		}
	}
	Rect.bottom=120;

	dc.FillRect(&Rect,&BlackBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&WhiteBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	dc.FillRect(&Rect,&BlackBrush);
	Rect.left+=PenWidth;
	Rect.right+=PenWidth;

	WhiteBrush.DeleteObject();
	BlackBrush.DeleteObject();
}

//////////////////////////
//	reverse a String	//
//////////////////////////
void CEANBarCode::ReverseString(CString &str)
{
	int iRight, iLeft, iLength_2;
	char ctemp;

	iLength_2 = (str.GetLength() / 2);

	for(iLeft=0, iRight=str.GetLength()-1;iLeft<iLength_2;iLeft++, iRight--)
	{
		ctemp =	str[iLeft];
		str.SetAt(iLeft, str[iRight]);
		str.SetAt(iRight, ctemp);
	}
}