/* -------------------------------------------

  Copyright (C) 2024-2025, Amlal El Mahrouss, all rights reserved.

------------------------------------------- */

#include <user/Opts.h>
#include <user/SystemCalls.h>

/// @file SystemCalls.cc
/// @brief Source file for the memory functions of the user.sys.

/// @brief Copy memory region.
IMPORT_C VoidPtr MmCopyMemory(_Input VoidPtr dest, _Input VoidPtr src, _Input SizeT len) {
  if (!len || !dest || !src) {
    return nullptr;
  }

  for (SizeT i = 0; i < len; i++) {
    ((Char*) dest)[i] = ((Char*) src)[i];
  }

  return dest;
}

/// @brief Get string length.
IMPORT_C SInt64 MmStrLen(const Char* in) {
  if (!in) return 0;

  SizeT len{0};

  do {
    ++len;
  } while (in[len] != '\0');

  return len;
}

/// @brief Fill memory region **dest** with **value**.
IMPORT_C VoidPtr MmFillMemory(_Input VoidPtr dest, _Input SizeT len, _Input UInt8 value) {
  if (!len || !dest) {
    return nullptr;
  }

  for (SizeT i = 0; i < len; i++) {
    ((Char*) dest)[i] = value;
  }

  return dest;
}

IMPORT_C Ref IoOpenFile(_Input const Char* path, _Input const Char* drv_letter) {
  return sci_syscall_arg_3(1, reinterpret_cast<VoidPtr>(const_cast<Char*>(path)),
                           reinterpret_cast<VoidPtr>(const_cast<Char*>(drv_letter)));
}

IMPORT_C Void IoCloseFile(_Input Ref desc) {
  sci_syscall_arg_2(2, desc);
}

IMPORT_C UInt64 IoSeekFile(_Input Ref desc, _Input UInt64 off) {
  auto ret = (UInt64*) sci_syscall_arg_3(3, reinterpret_cast<VoidPtr>(desc),
                                         reinterpret_cast<VoidPtr>(&off));

  MUST_PASS((*ret) != ~0UL);
  return *ret;
}

IMPORT_C UInt64 IoTellFile(_Input Ref desc) {
  auto ret = (UInt64*) sci_syscall_arg_2(4, reinterpret_cast<VoidPtr>(desc));
  return *ret;
}

/// @brief Print to the file descriptor.
/// @param desc the file descriptor.
IMPORT_C SInt32 PrintOut(_Input IORef desc, const char* fmt, ...) {
  va_list args;

  va_start(args, fmt);

  auto ret = (UInt64*) sci_syscall_arg_4(5, reinterpret_cast<VoidPtr>(desc),
                                         reinterpret_cast<VoidPtr>(const_cast<Char*>(fmt)), args);

  va_end(args);

  return *ret;
}

/// @internal
IMPORT_C Void _rtl_assert(Bool expr, const Char* origin) {
  if (!expr) {
    PrintOut(nullptr, "Assertion failed: %s\r", origin);
    PrintOut(nullptr, "Origin: %s\r", origin);
  }
}