/* $Id: hops.c,v 1.2 2003/11/17 00:48:43 grog Exp grog $ */
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/file.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <unistd.h>
#include "beer.h"

void usage (char *myname)
{
  fprintf (stderr,
	   "Usage:\n"
	   "%s [-a <alpha acid>] [-e <extract percentage>] [-I <desired IBU>]  [-v] litres\n\n"
	   "\tAt least one must be specified\n",
	   myname );
  }

float aa_factor;
float extract_factor;
float total_hops;					    /* total weight of hops */
float total_aa;						    /* total alpha acid */
float total_extracted;					    /* total alpha acid extracted */
float ibu;

float litres;

float desired_ibu;

int verbose = 1;

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

  for (i = 1; i < argc; i++)
    {
    if (argv [i] [0] == '-')
      {
      if (memcmp (argv [i], "-a", 2) == 0)		    /* alpha acid percentage */
	{
	if (argv [i] [2])				    /* speficied percentage */
	  {
	  aa_factor = atof (&argv [i] [2]);
	  if (aa_factor > 1)				    /* percentage? */
	    aa_factor /= 100;				    /* convert to factor */
	  else if (aa_factor == 0)
	    aa_factor = 0.05;
	  }
	else if (aa_factor == 0)
	  {
	  fprintf (stderr, "Warning: no alpha acid percentage specified, assuming 5%%\n");
	  aa_factor = 0.05;
	  }

	if (extract_factor == 0)
	  {
	  fprintf (stderr, "Warning: no extract factor specified, assuming 30%%\n");
	  extract_factor = 0.3;
	  }

	if (argc < (i + 2))
	  {
	  fprintf (stderr, "No weight specified for Alpha Acid\n\n");
	  usage (argv [0]);
	  return 1;
	  }
	else
	  {
	  double weight = atof (argv [i + 1]);
	  double aa;
	  double extracted;

	  aa = weight * aa_factor;
	  extracted = aa * extract_factor;
	  total_hops += weight;
	  total_aa += aa;
	  total_extracted += extracted;

	  if (verbose)
	    printf ("Hops (g)\talpha acid %%\textract %%\tmg alpha acid\n"
		    "%6.2f\t\t%6.2f\t\t%6.2f\t\t%6.4f\n",
		    weight,
		    aa_factor * 100,
		    extract_factor * 100,
		    extracted );
	  i++;
	  }
	}
      else if (memcmp (argv [i], "-e", 2) == 0)		    /* extract percentage */
	{
	if (argc < (i + 2))
	  {
	  fprintf (stderr, "No value specified for extract percentage\n\n");
	  usage (argv [0]);
	  return 1;
	  }
	else
	  {
	  extract_factor = atof (argv [i + 1]);
	  if (extract_factor > 1)			    /* percentage */
	    extract_factor /= 100;			    /* convert to factor */
	  i++;
	  }
	}
      else if (memcmp (argv [i], "-I", 2) == 0)		    /* desired IBUs */
	{
	if (argc < (i + 2))
	  {
	  fprintf (stderr, "No value specified for desired IBU\n\n");
	  usage (argv [0]);
	  return 1;
	  }
	else
	  {
	  desired_ibu = atof (argv [i + 1]);
	  i++;
	  }
	}
      else if (strcmp (argv [i], "-v") == 0)		    /* verbose */
	{
	verbose++;
	printf ("Hops\t\t\tconcen-\t\tweight\tequiv\t\ttotal\n"
		"\t\t\ttration %%\t(kg)\tsucrose (kg)\tsugar (kg)\n\n");
	}
      }
    else if (litres == 0.0)
      litres = atof (argv [i]);
    else						    /* too much */
      {
      fprintf (stderr, "Extraneous parameter:%s\n", argv [i]);
      usage (argv [0]);
      return 1;
      }
    }

  if (litres == 0.0)
    {
    fprintf (stderr, "No volume gives no beer\n");
    usage (argv [0]);
    return 1;
    }

  ibu = total_extracted * 1000 / litres;		    /* mg/litre */

  printf ("IBU: %6.2f\n", ibu);

  return 0;
  }