#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

int bbits = 4;    // 16 bytes per block
int sbits = 4;    // 16 sets
int E = 1;        // direct-mapped cache
int verbose = 0;   // default of NOT verbose
FILE *infile = NULL;
char *filename = "NOFILE";

void usage(char * prog)
{
  fprintf(stderr, "Usage: %s -v -s <bits> -b <bits> -E <count> -t <file>\n",
	  prog);
  exit(1);
}

void processArgs(int argc, char** argv)
{
  char c;

  infile = stdin;
  while((c = getopt(argc, argv, "b:s:E:t:vhq")) != -1) {
    switch(c) {
    case 'v':
      verbose = 1 - verbose;
      break;
    case 'h':
      usage(argv[0]);
      break;
    case 'q':
      verbose = 0;
      break;
    case 't':
      filename = strdup(optarg);
      infile = fopen(filename, "r");
      if (!infile) {
	fprintf(stderr, "Cannot open file %s\n", optarg);
	usage(argv[0]);
      }
      break;
    case 'E':
      E = strtol(optarg, NULL, 0);
      if (E <=0 ) {
	if (E == 0 && errno == EINVAL) {
	  fprintf(stderr, "Unable to convert -E argument: %s\n", optarg);
	} else {
	  fprintf(stderr, "Invalid argument to -E: %d\n", E);
	}
	usage(argv[0]);
      }
      break;
    case 's':
      sbits = strtol(optarg, NULL, 0);
      if (sbits <=0 ) {
	if (sbits == 0 && errno == EINVAL) {
	  fprintf(stderr, "Unable to convert -s argument: %s\n", optarg);
	} else {
	  fprintf(stderr, "Invalid argument to -s: %d\n", sbits);
	}
	usage(argv[0]);
      }
      break;
    case 'b':
      bbits = strtol(optarg, NULL, 0);
      if (bbits <=0 ) {
	if (bbits == 0 && errno == EINVAL) {
	  fprintf(stderr, "Unable to convert -b argument: %s\n", optarg);
	} else {
	  fprintf(stderr, "Invalid argument to -b: %d\n", bbits);
	}
	usage(argv[0]);
      }
      break;
    default:
      usage(argv[0]);
    }
  }
}
void printCachesimResults(int hits, int misses, int evictions)
{
  printf("     Hits: %d\n", hits);
  printf("   Misses: %d\n", misses);
  printf("Evictions: %d\n", evictions);
}

int main(int argc, char **argv)
{
  int hits = 0;
  int misses = 0;
  int evictions = 0;

  processArgs(argc, argv);

  if (verbose) {
    printf("E = %2d, s = %2d, b = %2d, file: %s\n",
	   E, sbits, bbits, filename);
  }

  /* Fill in the body of the simulator here */
  
  printCachesimResults(hits, misses, evictions);

  return 0;
}