Convert JavaScript to Delphi?

Question

JavaScript

Hello, please help me to find the error in the code

var a = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMN0PQRSTUVWXYZO123456789+/="
function o(t) {
    if (!t || t.length % 4 == 1)
        return !1;
    for (var i, e, o = 0, s = 0, r = ""; e = t.charAt(s++); ){
        e = a.indexOf(e), ~e && (i = o % 4 ? 64 * i + e : e, o++ % 4) && (r += String.fromCharCode(255 & i >> (-2 * o & 6)));
    }
    return r

function sar32(value, shift: longint): longint;
asm
  mov ecx, edx
  sar eax, cl
  end;

function FromCharCode(ch:array of byte):AnsiString;
var L:Integer;
begin
    L := Length(ch);
    SetLength(result, L);
    if L > 0 then Move(ch[0], result[1], L);
end;

function o(t:string): string;
var
o, s, i, eint :integer;
r :string;
ch : array[0..500] of byte;
ec : char;
const
a : string = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMN0PQRSTUVWXYZO123456789+/=';
begin
o := 0;
i := 0;
if (t = '') or (Length(t) mod 4 = 1) then
  r := 'False';
for s := 1 to Length(t) do
  begin
    eint := AnsiPos(t[s], a) - 1;
    if eint <> -1 then
      begin
        i := ifThen((o mod 4) <> 0, 64 * i + eint, eint);
        o := o + 1;
        ch[s] := (255 and sar32(i, (-2 * o and 6)));
        if inttostr(ch[s]) <> '0' then
          begin
            r := r + FromCharCode(ch[s]);
          end;
      end;
  end;
  result := r;
end;

An example of calling JS

a in Delphi does not quite correctly work out

the link to the js source code

Answer 1

This doesn’t even look like laboratory work, rather like a project of some kind of bot, so the logical question is: I’ll leave everything here and I’ll help you, but will you get money?
You do not need help, the problem is solvable, there are at least two ways, the first is to learn to analyze and debug, the second is an alternative, connect a ready-made JS "engine", if you wanted, you would solve it faster than me, since you are in the know I don't even know what it is or where.
And the #bytecode tag has nothing to do with it.

Answer 2

figured out, the problem was also due to differences in functions
and in delphi

chr(0) // ничего не возвращает
//заменил на 
chr(32) // ->> ' '