/*************************************************
  filename: printqueue.c
  author:   dan brown
  email:    snowman@cs.cornell.edu
  date:     25 august 1997

  This is the source code to CS 410 programming assignment #1.
  The problem is to develop a simulator for a print queue, under 
  odd circumstances.
  *************************************************/

#include <stdlib.h>
#include <stdio.h>
#include "queue.h"

int main ()
{
  int nMinutes;                /* minutes in simulation */
  int nSeed;                   /* seed for generator */
  int nCurrMin= 1;             /* current minute in simulation */
  Queue qAdmin;                /* the two queues */
  Queue qFaculty;
  int nAdminQueued = 0;        /* how many jobs of each type queued */
  int nFacultyQueued = 0;
  int nAdminRun = 0;           /* how many of each type executed */
  int nFacultyRun = 0;
  int nAdminWaitSum = 0;       /* sum of time of each type spent in queue */
  int nFacultyWaitSum = 0;
  double fAdminWait;           /* mean wait in queue for each job type */
  double fFacultyWait;


  printf ("How many minutes in simulation? ");
  scanf ("%d", &nMinutes);

  printf ("Seed for random number generator? ");
  scanf ("%d", &nSeed);
  srand (nSeed);

  QInitialize (&qAdmin);
  QInitialize (&qFaculty);

  for (nCurrMin = 1; nCurrMin <= nMinutes; ++nCurrMin)
    {
      int nCurrJobTime;  /* Time that extracted job was put into the queue */

      printf ("Minute %d: printed ", nCurrMin);

      /* extract job from queue.  check admin queue first. */

      if (!QEmpty(qAdmin))
	{
	  nCurrJobTime = QExtract (&qAdmin);
	  printf ("admin job from minute #%d",nCurrJobTime);
	  nAdminRun++;
	  nAdminWaitSum += (nCurrMin - nCurrJobTime);
	}
      else if (!QEmpty (qFaculty))
	{
	  nCurrJobTime = QExtract (&qFaculty);
	  printf ("faculty job from minute #%d", nCurrJobTime);
	  nFacultyRun++;
	  nFacultyWaitSum += (nCurrMin - nCurrJobTime);
	}
      else
	/* both queues are empty */
	printf ("no job");

      /* add new jobs to queue. */

      printf (", added: ");
      if (rand() < (0.5 * RAND_MAX)) 
	{
	  printf ("admin ");
	  nAdminQueued++;
	  QInsert (&qAdmin, nCurrMin);
	}
      if (rand() < (0.4 * RAND_MAX))
	{
	  printf ("faculty");
	  nFacultyQueued++;
	  QInsert (&qFaculty, nCurrMin);
	}
      printf ("\n");
    }

  printf ("\nSummary:\n");

  /* compute mean times in queue.  avoid dividing by 0 */

  if (nAdminRun > 0)
    fAdminWait = nAdminWaitSum / nAdminRun;
  else
    fAdminWait = 0.0;

  if (nFacultyRun > 0)
    fFacultyWait = nFacultyWaitSum / nFacultyRun;
  else
    fFacultyWait = 0.0;

  /* print results */
  
  printf ("Admin jobs: %d out of %d printed.  Average wait: %0.1f min\n",
	  nAdminRun, nAdminQueued, fAdminWait);
  printf ("Faculty jobs: %d out of %d printed.  Average wait: %0.1f min\n",
	  nFacultyRun, nFacultyQueued, fFacultyWait);
	
  QDestroy (&qAdmin);
  QDestroy (&qFaculty);
  return 0;
}