//---------------------------------------------------------------------------
// Generowanie kodow kreskowych Standard Code 2 of 5
// www.algorytm.org
// (c)2006 Tomasz Lubinski
//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"

char codeS25sign[10] = {
      '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'
      };
      
char codeS25bars[10][14] = {
     {1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0},
     {1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0},
     {1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0},
     {1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0},
     {1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0},
     {1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0},
     {1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0},
     {1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0},
     {1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0},
     {1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0}
     };

char start[8] = { 
        1, 1, 0, 1, 1, 0, 1, 0
        };
        
char stop[8] = { 
        1, 1, 0, 1, 0, 1, 1, 0
        };
        

TForm1 *Form1;
int curentPos;


// returns 1 if letter is correct, 0 otherwise
int checkLetter(char ch)
{
        for (int i=0; i<10; i++)
                if (codeS25sign[i] == ch)
                        return 1;

        return 0;
}

// reurns 1 if txt is correct, 0 otherwise
int check(char *txt)
{
        for (unsigned int i=0; i<strlen(txt); i++)
                if (checkLetter(txt[i]) == 0)
                        return 0;

        return 1;
}

// returns letter value for check digit
int getLetterValue(char ch)
{
        for (int i=0; i<10; i++)
                if (codeS25sign[i] == ch)
                        return i;

        return 0;
}

// return check digit
int checkDigit(char *txt)
{
        int sum = 0;
        int w1 = 0;
        int w2 = 0;        

        for (unsigned int i=0; i<strlen(txt); i++)
        {
                if (i % 2 == 0) 
                {
                    w1 += getLetterValue(txt[i]);
                }
                else
                {
                    w2 += getLetterValue(txt[i]);                
                }
        }
        
        if (strlen(txt) % 2 == 0)
        {
                w2 *= 3;
        }
        else
        {
                w1 *= 3;        
        }
        
        sum = w1+ w2;
        sum %= 10;
        sum = 10 - sum;
        sum %= 10;

        return sum;
}

void drawSignBars(char bars[], int count)
{
        Form1->Image1->Canvas->Brush->Color = clBlack;

        //print bars
        for (int i=0; i<count; i++)
        {
                if (bars[i] == 1)
                        Form1->Image1->Canvas->Rectangle(curentPos + 20, 10, curentPos + 22, 100);

                curentPos += 2;
        }   
}

void drawBars(char *txt)
{
        curentPos = 0;
        Form1->Image1->Canvas->Brush->Color = clWhite;
        Form1->Image1->Canvas->Rectangle(0, 0, 441, 121);

        //print start character
        drawSignBars(start, 8);
        
        //print characters
        for (unsigned int i=0; i<strlen(txt); i++)
                for (int j=0; j<10; j++)
                        if (codeS25sign[j] == txt[i])
                        {
                                drawSignBars(codeS25bars[j], 14);
                                break;
                        }        

        //print check digit
        drawSignBars(codeS25bars[checkDigit(txt)], 14);
        
        //print stop character
        drawSignBars(stop, 8);

        //Draw text
        Form1->Image1->Canvas->Font->Size = 10;
        Form1->Image1->Canvas->Brush->Color = clWhite;
        Form1->Image1->Canvas->Font->Color = clBlack;
        Form1->Image1->Canvas->TextOut(curentPos/2 + 20 - strlen(txt)*3, 100, txt);        
}

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------


void __fastcall TForm1::Button1Click(TObject *Sender)
{
        if (check(Kod->Text.c_str()) == 0)
        {
                ShowMessage("Incorrect text");
                return;
        }

        drawBars(Kod->Text.c_str());
}
//---------------------------------------------------------------------------