#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include "fakedisc.h"

/* Reminders from fakedisc.h

  typedef unsigned char byte;
  typedef byte block[512];

  int createdisc(const char *name, int number_of_blocks);
  int mountdisc(const char *name);
  void dismountdisc(int discnum);

  int discsize(int discnum);
  int writeblock(int discnum, int blocknum, void *b);
  int readblock(int discnum, int blocknum, void *b);
*/

void main()
{ char line[1000];
  char * part[100];
  int numparts, dnum = -1;
  while (true)
  { printf("> ");
    char * s = fgets(line, 999, stdin);
    if (s==NULL) break;
    numparts = 0;
    s = strtok(line, " \r\n");
    while (s != NULL)
    { part[numparts] = s;
      numparts += 1;
      s = strtok(NULL, " \r\n"); }

    if (numparts == 0)
      continue;

    else if (strcmp(part[0], "?") == 0)
    { printf("   create name number-of-blocks\n");
      printf("   m name\n");
      printf("   r block-number\n");
      printf("   w block-number string-with-no-spaces\n");
      printf("   x\n"); }

    else if (strcasecmp(part[0], "create") == 0)
    { bool ok = createdisc(part[1], atol(part[2]));
      if (ok)
      { dnum = mountdisc(part[1]);
        printf("OK, \"%s\", %d blocks\n", part[1], discsize(dnum)); }
      else
        printf("create failed\n"); }

    else if (strcasecmp(part[0], "m") == 0)
    { dnum = mountdisc(part[1]);
      if (dnum < 0)
        printf("mount failed\n");
      else
        printf("%d blocks\n", discsize(dnum)); }

    else if (strcasecmp(part[0], "r") == 0)
    { if (dnum < 0)
      { printf("no disc mounted\n");
        continue; }
      int blocknum = atol(part[1]);
      block buffer;
      bool ok = readblock(dnum, blocknum, buffer);
      if (ok)
        printf("%s\n", (char *)buffer);
      else
        printf("read failed\n"); }

    else if (strcasecmp(part[0], "w") == 0)
    { if (dnum < 0)
      { printf("no disc mounted\n");
        continue; }
      int blocknum = atol(part[1]);
      bool ok = writeblock(dnum, blocknum, part[2]);
      if (!ok)
        printf("write failed\n"); }

    else if (strcasecmp(part[0], "x") == 0)
    { if (dnum >= 0)
        dismountdisc(dnum);
      break; }

    else
      printf("unrecognised command \"%s\"\n", part[0]); } }