/**
 * Groupmembers:
 * 1. Anna Schlittenhardt
 * 2. Tuan-Dat Tran
 */

#include <stdlib.h>
#include <stdio.h>
#include <getopt.h>
#include <ctype.h>
#include <string.h>
#include <math.h>
#include "cachelab.h"

int v = 0; /* verbose */
int s = 0; /* set index */
int E = 0; /* Set of cache lines */
int b = 0; /* Block offset */
int S; /* Set of Set of cache lines*/
int B; /* Block size */
long long time = 0;
FILE *tracefile; /* File to trace from */
struct cache_line **cache; /* cache */

int hit = 0, miss = 0, eviction = 0;

struct cache_line {
  unsigned char v;
  unsigned int tag;
  unsigned int time;
};

void print_help() {
  printf("Usage: ./csim-ref [-hv] -s <s> -E <E> -b <b> -t <tracefile>\n");
  printf("  -h: Optional help flag that prints usage info\n");
  printf("  -v: Optional verbose flag that displays trace info\n");
  printf("  -s <s>: Number of set index bits (S = 2 s is the number of sets)\n");
  printf("  -E <E>: Associativity (number of lines per set)\n");
  printf("  -b <b>: Number of block bits (B = 2 b is the block size)\n");
  printf("  -t <tracefile>: Name of the valgrind trace to replay\n");
}

void init() {
  cache = (struct cache_line **) malloc(S*sizeof(struct cache_line *));
  for (int i = 0; i < S; i++) {
    struct cache_line* cache_set =  (struct cache_line *) malloc(E*sizeof(struct cache_line));
    cache[i] = cache_set;
    for (int j = 0; j < E; j++) {
      cache_set[j].v = 0;
      cache_set[j].tag = 0;
      cache_set[j].time = 0;
    }
  }
}

void clean() {
  for (int i = 0; i < S; i++) {
    free(cache[i]);
  }
  free(cache);
  fclose(tracefile);
}

void accessMem (int addr) {
  unsigned int set = ((addr >> b) & ((1LL << s) - 1));
  unsigned int tag = addr >> (b + s);
  struct cache_line *cache_set = cache[set];
  long evic_time = 0;
  int evic_line = 0;
  for (int i = 0; i < E; i++) {
    if (cache_set[i].tag == tag && cache_set[i].v != 0){
      if (v) { printf("hit "); }
      hit++;
      cache_set[i].time = time;
      time++;
      return;
    }
  }

  if (v) { printf("miss "); }
  miss++;

  for (int i = 0; i < E; i++) {
    if (cache_set[i].time < evic_time) {
      evic_line = i;
      evic_time = cache_set[i].time;
    }
  }

  if (cache_set[evic_line].v == 1) {
    if (v) { printf("eviction "); }
    eviction++;
  }

  cache_set[evic_line].v = 1;
  cache_set[evic_line].tag = tag;
  cache_set[evic_line].time = time;
  time++;
  return;
}

void trace() {
  char op;
  unsigned address;
  int size;

  while (fscanf(tracefile, " %c %x,%d", &op, &address, &size) > 0 ) {
    switch (op) {
    case 'M':
      if (v) { printf("%c %x,%d ", op, address, size); }
      accessMem(address);
      accessMem(address);
      printf("\n");
      break;
    case 'L':
      if (v) { printf("%c %x,%d ", op, address, size); }
      accessMem(address);
      printf("\n");
      break;
    case 'S':
      if (v) { printf("%c %x,%d ", op, address, size); }
      accessMem(address);
      printf("\n");
      break;
    }
  }
}

int main(int argc, char *argv[]) {
  char c;
  while ((c = getopt(argc, argv, "s:E:b:t:vh")) != -1) {
    switch (c) {
    case 'h':
      print_help();
      exit(0);
      break;
    case 'v':
      v = 1;
      break;
    case 's':
      s = atoi(optarg);
      break;
    case 'E':
      E = atoi(optarg);
      break;
    case 'b':
      b = atoi(optarg);
      break;
    case 't':
      tracefile = fopen(optarg, "r");
      break;
    }
  }

  if (s == 0 || E == 0 || b == 0 || tracefile == NULL) {
    print_help();
    exit(1);
  }

  S = pow(2, s);
  B = pow(2, b);

  init();
  trace();
  for (int i = 0; i < S; i++) {
    for (int j = 0; j < E; j++) {
      // printf("cache[%d][%d]: %c %x %ul\n", i, j, cache[i][j].v, cache[i][j].tag, cache[i][j].time);
    }
  }
  clean();

  printSummary(hit, miss, eviction);
  return 0;
}