/*
 * Copyright 2020, Data61
 *
 * This software may be distributed and modified according to the terms of
 * the GNU General Public License version 2. Note that NO WARRANTY is provided.
 * See "LICENSE_GPLv2.txt" for details.
 *
 * @TAG(DATA61_GPL)
 */

$esc:(#include <stdio.h>)
$esc:(#include <string.h>)
$esc:(#include <stdint.h>)
$esc:(#include <stddef.h>)

typedef char EntryBlock;
typedef char CString;
typedef void *SysState;

#define SIZE 4096

#include "generated.c"
#include <gum/anti/iterator.ac>
#include <gum/anti/common.ac>

char block[SIZE]; // Contains Entry's jammed together; terminated by
                  // len==0.

$ty:((SysState, EntryBlock!)) $id:get_block ($ty:(SysState) args) {
   $ty:((SysState, EntryBlock!)) ret;
   ret.p1 = args;
   ret.p2 = block;
   return ret;
}

$ty:(Entry!) $id:get_entry_at_offset ($ty:((EntryBlock!, U64)) args) {
   $ty:(EntryBlock!) block = args.p1;
   $ty:(U64) offset = args.p2;
   return ($ty:(Entry))((uintptr_t)block + offset);
}

$ty:(Bool) $id:is_entry ($ty:((EntryBlock!, Entry!)) args) {
   $ty:(Bool) ret;
   $ty:(Entry!) e = args.p2;
   $ty:(EntryBlock!) block = args.p1;
   ret.boolean = ((uintptr_t)e - (uintptr_t)block) < SIZE;
}

$ty:(Bool) cstring_cmp($ty:((CString!, CString!)) args) {
   $ty:(Bool) ret;

   if (!strcmp(args.p1, args.p2)) {
      ret.boolean = 1;
   } else {
      ret.boolean = 0;
   }

   return ret;
}

$ty:(Stuff!) stuff_ptr($ty:(Entry!) e) {
   return &e->stuff;
}

int in_range($ty:(Entry!) e, unsigned long nlen) {
  unsigned long p;

  p = (uintptr_t)e + offsetof(Entry,name) + nlen;

  return (p - (uintptr_t)block) < SIZE;
}

/* Initialise our block of entries. */
/* Not translated into Cogent. */
void init(void) {
  FILE *fp;
  $ty:(Entry) e;
  int a, b, c, len;
  char buf[80];

  memset(block, 0, SIZE);

  if ((fp = fopen("entries.txt", "r")) != NULL) {
    e = (Entry *)block;
    while (fscanf(fp, "%s%d%d%d\n", buf, &a, &b, &c) == 4) {
      len = strlen(buf)+1;
      if (!in_range(e, len)) {
        break;
      }
      // Point to the next location 
      e->name = (char*)((uintptr_t)e + offsetof(Entry,name) + sizeof(char*));
      strcpy(e->name, buf);
      e->stuff.a = a;
      e->stuff.b = b;
      e->stuff.c = c;
      e->len = ((uintptr_t)e->name + len) - (uintptr_t)e;
      e = (Entry *) ((uintptr_t)e + e->len);
    }
    fclose(fp);
  }
}

int main(void){
  $ty:((SysState, Option Stuff!)) ret;
  init();
  char *str = {"wombat"};
  $ty:((SysState, CString!)) args = {.p1 = NULL , .p2 = str};
  ret = findStuff(args);
  if (ret.p2.tag == TAG_ENUM_Some) {
    printf("Wombat's b is %d.\n", ret.p2.Some->b);
  } else {
    printf("Wombat was not found.\n");
  }
  return 0;
}