var tocjent;
var public_key;
var private_key;

function calculate()
{
   number1 = document.getElementById("first-prime").value;
  number2 = document.getElementById("second-prime").value;
  result = number1*number2;
 document.getElementById("product-span").innerHTML=result;
 tocjent = (number1-1)*(number2-1);
 document.getElementById("tocjent-span").innerHTML=tocjent;
}

function check()
{
 public_key = 5;
 while(euklides(tocjent, public_key)!=1)
  {
   public_key++;
  }
  document.getElementById("check-span").innerHTML = public_key;
 temp = tocjent;
 i = 1;
 while((temp+1)%public_key!=0)
  {
   i++;
   temp = temp * i;
  }
 private_key=(temp+1)/public_key;
 document.getElementById("private-key").innerHTML=private_key;
}

function euklides(a, b)
{
   while(b!=0)
   {
     c=a%b;
     a=b;
     b=c;
   }
   return a;
}

function power_mod(a,b,c)
{
 temp=1;
 a = a%c;
 for(i=1;i<=b;i++)
  {
    temp=temp*a;
    temp=temp%c;
  }
 return temp;
}

function crypt()
{
    pt = document.getElementById("plaintext").value;
    pp = document.getElementById("product-prime").value;
    pk = document.getElementById("de-public-key").value;
    document.getElementById("code-text").innerHTML=(power_mod(pt,pk,pp));
}

function decrypt()
{
 prk=document.getElementById("en-private-key").value;
 ct=document.getElementById("en-code-text").value;
 pprime=document.getElementById("en-product-prime").value;
 document.getElementById("en-code-result").innerHTML=(power_mod(ct,prk,pprime));
}