// Copyright 2024-2025, Amlal El Mahrouss (amlal@nekernel.org)
// Licensed under the Apache License, Version 2.0 (see LICENSE file)
// Official repository: https://github.com/ne-foss-org/nekernel

#ifndef BOOTKIT_SUPPORT_H
#define BOOTKIT_SUPPORT_H

/// @file Support.h
/// @brief Purpose of this file is to help port libs into the bootloader.

#ifndef __NE_ARM64__
#include <string.h>
#endif

#define kLongMax ((long) (~0UL >> 1))
#define kLongMin (~kLongMax)

#ifdef __BOOTZ__

/// @brief memset definition in C++.
/// @param dst destination pointer.
/// @param byte value to fill in.
/// @param len length of of src.
EXTERN_C void* memset(void* dst, int byte, long long unsigned int len);

/// @brief memcpy definition in C++.
/// @param dst destination pointer.
/// @param  src source pointer.
/// @param len length of of src.
EXTERN_C void* memcpy(void* dst, const void* src, long long unsigned int len);

/// @brief strlen definition in C++.
EXTERN_C size_t strlen(const char* whatToCheck);

/// @brief strcmp definition in C++.
EXTERN_C int strcmp(const char* whatToCheck, const char* whatToCheckRight);

#else

#ifndef __NE_ARM64__
#include <string.h>
#endif

#endif  // __BOOTZ__

#define SetMem(dst, c, sz) memset(dst, c, sz)
#define MoveMem(dst, src, sz) memcpy(dst, src, sz)
#define CopyMem(dst, src, sz) memcpy(dst, src, sz)
#define StrLen(src) strlen(src)
#define StrCmp(dst, src) strcmp(dst, src)

inline int IsSpace(int c) {
  return c == ' ';
}

inline int StringNCompare(const char* destination, const char* source, long length) {
  long err = 0;

  for (long i = 0UL; i < length; ++i) {
    if (source[i] != destination[i]) ++err;
  }

  return err;
}

inline long StringToLong(const char* nptr, char** endptr, int base) {
  const char *p      = nptr, *endp;
  bool        is_neg = 0, overflow = 0;

  /* Need unsigned so (-kLongMin) can fit in these: */
  unsigned long n = 0UL, cutoff;
  int           cutlim;

  if (base < 0 || base == 1 || base > 36) {
    return 0L;
  }

  endp = nptr;

  while (IsSpace(*p)) p++;

  if (*p == '+') {
    p++;
  } else if (*p == '-') {
    is_neg = 1, p++;
  }
  if (*p == '0') {
    p++;
    /* For strtol(" 0xZ", &endptr, 16), endptr should point to 'x';
     * pointing to ' ' or '0' is non-compliant.
     * (Many implementations do this wrong.) */
    endp = p;
    if (base == 16 && (*p == 'X' || *p == 'x')) {
      p++;
    } else if (base == 2 && (*p == 'B' || *p == 'b')) {
      /* C23 standard supports "0B" and "0b" prefixes. */
      p++;
    } else if (base == 0) {
      if (*p == 'X' || *p == 'x') {
        base = 16, p++;
      } else if (*p == 'B' || *p == 'b') {
        base = 2, p++;
      } else {
        base = 8;
      }
    }
  } else if (base == 0) {
    base = 10;
  }

  cutoff = (is_neg) ? -(kLongMin / base) : kLongMax / base;
  cutlim = (is_neg) ? -(kLongMin % base) : kLongMax % base;

  while (1) {
    int c;
    if (*p >= 'A')
      c = ((*p - 'A') & (~('a' ^ 'A'))) + 10;
    else if (*p <= '9')
      c = *p - '0';
    else
      break;
    if (c < 0 || c >= base) break;
    endp = ++p;
    if (overflow) {
      /* endptr should go forward and point to the non-digit character
       * (of the given base); required by ANSI standard. */
      if (endptr) continue;
      break;
    }
    if (n > cutoff || (n == cutoff && c > cutlim)) {
      overflow = 1;
      continue;
    }
    n = n * base + c;
  }

  if (endptr) *endptr = (char*) endp;

  if (overflow) {
    return ((is_neg) ? kLongMin : kLongMax);
  }

  return (long) ((is_neg) ? -n : n);
}

#endif