/************************************************
CS317 Homework 1 Class ID Generator
By: Bin Lin
Date: March 31, 2004
*************************************************/

#include <iostream>
#include <string>

using namespace std;

int main(int argc, char* argv[]) {
  
  unsigned int ssn_num, ssn_p1, ssn_p2, ssn_p3;
  int rand1, rand2;
  int  ssn_p3_d1, ssn_p3_d4, sh1, sh2;
  char uuid[128];
  FILE *handler;

  if(argc != 2) {
    cerr << "Usage: " << argv[0] << "YOUR_9_DIGIT_SSN";
    exit(1);
  }
  
  if(strlen(argv[1]) != 9) {
    cerr << "SSN should have 9 digits";
    exit(1);
  }

  ssn_num = atoi(argv[1]);
  cout << "SSN_NUM: " << ssn_num << endl;
  
  ssn_p1 = ssn_num / 1000000;
  ssn_p2 = (ssn_num - ssn_p1 * 1000000) / 10000;
  ssn_p3 = ssn_num - ssn_p1 * 1000000 - ssn_p2 * 10000;
  
  ssn_p3_d1 = ssn_p3 / 1000;
  ssn_p3_d4 = ssn_p3 % 10;

  sh1 = ssn_p3_d1 * 10 + ssn_p3_d4;
  sh2 = (ssn_p3 - ssn_p3_d1 * 1000 - ssn_p3_d4) / 10;

  srand(ssn_p1);
  rand1 = rand() % 10000;

  srand(ssn_p2);
  rand2 = rand() % 10000;
  
  if(ssn_p3_d4 % 2)
	sprintf(uuid, "%d%d%c%c", rand1, rand2, sh1+65, sh2+65);
  else
	sprintf(uuid, "%c%c%d%d", sh1+65, sh2+65, rand1, rand2);

  cout << "Your unique class id is " << uuid << endl;

  handler = fopen("ID.txt", "w+");
  fprintf(handler, "Your unique class id is %s\n", uuid);
  fclose(handler);

  return 0;
}