#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "demo4_math.h"

#define BINARY_STR_LEN 16
#define MAX_STR_LEN 256

long unsigned init(long unsigned total, long unsigned new)
{
  return new;
}

long unsigned add(long unsigned total, long unsigned new)
{
  return total + new;
}

typedef struct {
  char *name;
  long unsigned (*func)(long unsigned, long unsigned);
} command;

command* commands[2];

command* find_func(char *line)
{
  command *cmd;
  cmd->name = "+";
  cmd->func = &add;
  commands[0] = cmd;

  command *cmd2;
  cmd2->name = "l";
  cmd2->func = &init;
  commands[1] = cmd2;

  return commands[0];
}

void error(char *msg)
{
  printf("%s\n", msg);
  exit(EXIT_FAILURE);
}

void remove_newline(char *input)
{
  for (; *input; input++)
  {
    if (*input == '\n')
      *input = 0;
  }
}

int main(void)
{
  char line[MAX_STR_LEN + 1];
  long unsigned total = 0;

  while (1)
  {
    printf("? ");
    fgets(line, MAX_STR_LEN, stdin);
    remove_newline(line);

    if (strlen(line) == 0)
      break;

    command *cmd = find_func(line);

    long unsigned current = numscan(line);
    total = cmd->func(total, current);

    printbin(total, BINARY_STR_LEN);
    printf(" (%lu)\n", total);
  }

  return EXIT_SUCCESS;
}