#include <common/fzl_extern.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <vm/internals/reader.h>

// Read external lib names
bool vm_rd_extern_libs(fzl_vm_reader_t *reader, FILE *fd)
{
  if (!reader || !fd)
    return false;

  uint16_t libs_count = reader->extern_libs_count;
  if (!libs_count)
    return true;

  reader->extern_libs = malloc(sizeof(char *) * libs_count);
  if (!reader->extern_libs)
  {
    snprintf(internal_error, sizeof(internal_error), "out of memory");
    return false;
  }

  memset(reader->extern_libs, 0, sizeof(char *) * libs_count);

  bool ok        = false;
  size_t name_sz = 0;
  char name[256];
  for (uint16_t i = 0; i < libs_count; i++)
  {
    memset(name, 0, sizeof(name));

    ok = vm_rd_word(fd, 1, &name_sz);
    if (!ok || name_sz < 1)
    {
      snprintf(internal_error, sizeof(internal_error),
               "failed to read lib #%u name size", i);
      return false;
    }

    ok = vm_rd_char(fd, name_sz, name);
    if (!ok)
    {
      snprintf(internal_error, sizeof(internal_error),
               "failed to read lib #%u name", i);
      return false;
    }

    char *val = malloc(sizeof(char) * name_sz + 1);
    if (!val)
    {
      snprintf(internal_error, sizeof(internal_error),
               "out of memory on lib #%u name allocation", i);
      return false;
    }

    memset(val, 0, sizeof(char) * name_sz + 1);
    memcpy(val, name, sizeof(char) * name_sz);
    reader->extern_libs[i] = val;
  }

  return true;
}