//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
AnsiString _StrToHex(char *str,int len)
{
        AnsiString s="";
        for(int i= 0 ;i<len;i++)
                s=s + IntToHex((unsigned char)(str[i]), 2 ) + ",";
        return s;
};
int _Sum(unsigned char *s,int len)
{
        int n= 0 ;
        for(int i= 0 ;i<len;i++)
                n+=s[i];
        return n;
};
void Encode(unsigned char *t,int tl,unsigned char *o,int ol,unsigned char *k,int kl)
{
        int s=_Sum(k,kl),n=s,n0,ci= 0 ;
        for(int i= 0 ;i<tl;i++)
        {
                n0=(int)(t[i])+(int)(k[ci])+n+s;
                n=t[i];
                o[i]=n0% 256 ;
                if((++ci)>=kl)
                        ci= 0 ;
        };
};
void Decode(unsigned char *t,int tl,unsigned char *o,int ol,unsigned char *k,int kl)
{
        int s=_Sum(k,kl),n=s,n0,ci= 0 ;
        for(int i= 0 ;i<tl;i++)
        {

                o[i]=t[i]-(int)k[ci]-n-s;
                n0=(BYTE)((o[i])+(int)(k[ci])+n+s);
                n=o[i];
                if((++ci)>=kl)
                        ci= 0 ;
        };
};
void __fastcall TForm1::Button1Click(TObject *Sender)
{
        int al=Edit1->Text.Length(),
                bl=RichEdit1->Text.Length(),
                cl=RichEdit1->Text.Length();
        char *a=new char[al+ 1 ];
        char *b=new char[bl+ 1 ];
        char *c=new char[cl+ 1 ];
        StrCopy(a,Edit1->Text.c_str());
        StrCopy(b,RichEdit1->Text.c_str());
        Encode(b,bl,c,cl,a,al);
        c[cl]= 0 ;
        RichEdit3->Text=_StrToHex(c,cl);
        RichEdit2->Text=c;
        ZeroMemory(b,bl);
        Decode(c,cl,b,bl,a,al);
        RichEdit4->Text=b;
        delete a,b,c;
}
//---------------------------------------------------------------------------

 n0=(BYTE)((o[i])+(int)(k[ci])+n+s);
 

void EncodeOneTimeNotepad(unsigned char *t,int tl,unsigned char *o,int ol,unsigned char *k,int kl)
{
        int ci= 0 ;
        for(int i= 0 ;i<tl;i++)
        {
                o[i]=(t[i]+k[i])% 256 ;
                if((++ci)>=kl)
                        ci= 0 ;
        };
};