//This program compiled and ran until I put /*******/ on top of some words
//Help administrator add a new name and password to the "passwd" file
#include <stdexcept>
#include <typeinfo>
#include <iostream>
#include <fstream>
#include "SecureBuffer.h"

using namespace std;

int main(int argc, char * argv[])
{
 try{

  if(argc !=3 )
  {
	cerr <<"Usage: add name password\n";
	exit(1);
  }

  Buffer id(argv[1]);
  SecureBuffer password(argv[2], id);

  /*******/ passwd("passwd", ios::in | ios::out);
  const int record_size= sizeof(Buffer)+sizeof(SecureBuffer);
  // Format of "passwd" is in list.cpp.  File= record* blank*. record=Buffer SecureBuffer.

  if(!passwd)
  {
    throw runtime_error("File passwd can not be opened\n");
  }
  int number_of_recs;
  passwd./*******/(0, ios::end);//in book
  number_of_recs=passwd.tellp()/record_size ;

  Buffer file_id;
  Buffer blank;// deleted data

  // find id in file
  int record_number;
  for(record_number=0; record_number<number_of_recs; record_number++)
  {
	  passwd.seekg(record_size*record_number);
	  passwd./*******/( (char*)&file_id, sizeof(id));
	  if( file_id==id)
	  {
		cout << record_number <<" : "<< file_id << endl;
		break;
          }
	  if( file_id==blank)
	  {
		cout << record_number <<" : "<< "(blank record)" << endl;
		break;
          }
  }//end for

  if(file_id==id)
  {
     // if id in file overwrite the password in the file
	passwd.seekp(record_size*record_number + sizeof(id));
	passwd.write( (char*)&password, sizeof(password));
  }else if(file_id==blank)
  {
     // if first slot is blank overwrite with user name and encrypted password
	passwd.seekp(record_size*record_number);
	passwd.write( (char*)&id, sizeof(id));
	passwd.write( (char*)&password, sizeof(password));
  }else
  {
     // if id not in file seek the last record and append id and password
	passwd.seekp(0, ios::end);
	passwd.write( (char*)&id, sizeof(id));
	passwd.write( (char*)&password, sizeof(/*******/));
  }

  passwd.close();

 }
 catch(exception &e)
 {
    cerr<< "Exception thrown: "<< typeid(e).name()<< " " << e.what()<<endl;
 } 

}