// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <algorithm>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iomanip>
#include <istream>
#include <iterator>
#include <limits.h>
#include <locale>
#include <sstream>
#include <string>
#include <vector>

#include "Common/CommonFuncs.h"
#include "Common/CommonPaths.h"
#include "Common/CommonTypes.h"
#include "Common/Logging/Log.h"
#include "Common/StringUtil.h"
#include "Common/Swap.h"

#ifdef _WIN32
#include <Windows.h>
constexpr u32 CODEPAGE_SHIFT_JIS = 932;
constexpr u32 CODEPAGE_WINDOWS_1252 = 1252;
#else
#include <codecvt>
#include <errno.h>
#include <iconv.h>
#include <locale.h>
#endif

#if !defined(_WIN32) && !defined(ANDROID) && !defined(__HAIKU__) && !defined(__OpenBSD__)
static locale_t GetCLocale()
{
  static locale_t c_locale = newlocale(LC_ALL_MASK, "C", nullptr);
  return c_locale;
}
#endif

std::string HexDump(const u8* data, size_t size)
{
  constexpr size_t BYTES_PER_LINE = 16;

  std::string out;
  for (size_t row_start = 0; row_start < size; row_start += BYTES_PER_LINE)
  {
    out += StringFromFormat("%06zx: ", row_start);
    for (size_t i = 0; i < BYTES_PER_LINE; ++i)
    {
      if (row_start + i < size)
      {
        out += StringFromFormat("%02hhx ", data[row_start + i]);
      }
      else
      {
        out += "   ";
      }
    }
    out += " ";
    for (size_t i = 0; i < BYTES_PER_LINE; ++i)
    {
      if (row_start + i < size)
      {
        char c = static_cast<char>(data[row_start + i]);
        out += std::isprint(c, std::locale::classic()) ? c : '.';
      }
    }
    out += "\n";
  }
  return out;
}

// faster than sscanf
bool AsciiToHex(const std::string& _szValue, u32& result)
{
  // Set errno to a good state.
  errno = 0;

  char* endptr = nullptr;
  const u32 value = strtoul(_szValue.c_str(), &endptr, 16);

  if (!endptr || *endptr)
    return false;

  if (errno == ERANGE)
    return false;

  result = value;
  return true;
}

bool CharArrayFromFormatV(char* out, int outsize, const char* format, va_list args)
{
  int writtenCount;

#ifdef _WIN32
  // You would think *printf are simple, right? Iterate on each character,
  // if it's a format specifier handle it properly, etc.
  //
  // Nooooo. Not according to the C standard.
  //
  // According to the C99 standard (7.19.6.1 "The fprintf function")
  //     The format shall be a multibyte character sequence
  //
  // Because some character encodings might have '%' signs in the middle of
  // a multibyte sequence (SJIS for example only specifies that the first
  // byte of a 2 byte sequence is "high", the second byte can be anything),
  // printf functions have to decode the multibyte sequences and try their
  // best to not screw up.
  //
  // Unfortunately, on Windows, the locale for most languages is not UTF-8
  // as we would need. Notably, for zh_TW, Windows chooses EUC-CN as the
  // locale, and completely fails when trying to decode UTF-8 as EUC-CN.
  //
  // On the other hand, the fix is simple: because we use UTF-8, no such
  // multibyte handling is required as we can simply assume that no '%' char
  // will be present in the middle of a multibyte sequence.
  //
  // This is why we look up the default C locale here and use _vsnprintf_l.
  static _locale_t c_locale = nullptr;
  if (!c_locale)
    c_locale = _create_locale(LC_ALL, "C");
  writtenCount = _vsnprintf_l(out, outsize, format, c_locale, args);
#else
#if !defined(ANDROID) && !defined(__HAIKU__) && !defined(__OpenBSD__)
  locale_t previousLocale = uselocale(GetCLocale());
#endif
  writtenCount = vsnprintf(out, outsize, format, args);
#if !defined(ANDROID) && !defined(__HAIKU__) && !defined(__OpenBSD__)
  uselocale(previousLocale);
#endif
#endif

  if (writtenCount > 0 && writtenCount < outsize)
  {
    out[writtenCount] = '\0';
    return true;
  }
  else
  {
    out[outsize - 1] = '\0';
    return false;
  }
}

std::string StringFromFormat(const char* format, ...)
{
  va_list args;
  va_start(args, format);
  std::string res = StringFromFormatV(format, args);
  va_end(args);
  return res;
}

std::string StringFromFormatV(const char* format, va_list args)
{
  char* buf = nullptr;
#ifdef _WIN32
  int required = _vscprintf(format, args);
  buf = new char[required + 1];
  CharArrayFromFormatV(buf, required + 1, format, args);

  std::string temp = buf;
  delete[] buf;
#else
#if !defined(ANDROID) && !defined(__HAIKU__) && !defined(__OpenBSD__)
  locale_t previousLocale = uselocale(GetCLocale());
#endif
  if (vasprintf(&buf, format, args) < 0)
  {
    ERROR_LOG(COMMON, "Unable to allocate memory for string");
    buf = nullptr;
  }

#if !defined(ANDROID) && !defined(__HAIKU__) && !defined(__OpenBSD__)
  uselocale(previousLocale);
#endif

  std::string temp = buf;
  free(buf);
#endif
  return temp;
}

// For Debugging. Read out an u8 array.
std::string ArrayToString(const u8* data, u32 size, int line_len, bool spaces)
{
  std::ostringstream oss;
  oss << std::setfill('0') << std::hex;

  for (int line = 0; size; ++data, --size)
  {
    oss << std::setw(2) << static_cast<int>(*data);

    if (line_len == ++line)
    {
      oss << '\n';
      line = 0;
    }
    else if (spaces)
      oss << ' ';
  }

  return oss.str();
}

// Turns "  hello " into "hello". Also handles tabs.
std::string StripSpaces(const std::string& str)
{
  const size_t s = str.find_first_not_of(" \t\r\n");

  if (str.npos != s)
    return str.substr(s, str.find_last_not_of(" \t\r\n") - s + 1);
  else
    return "";
}

// "\"hello\"" is turned to "hello"
// This one assumes that the string has already been space stripped in both
// ends, as done by StripSpaces above, for example.
std::string StripQuotes(const std::string& s)
{
  if (s.size() && '\"' == s[0] && '\"' == *s.rbegin())
    return s.substr(1, s.size() - 2);
  else
    return s;
}

bool TryParse(const std::string& str, u16* const output)
{
  u64 value;
  if (!TryParse(str, &value))
    return false;

  if (value >= 0x10000ull && value <= 0xFFFFFFFFFFFF0000ull)
    return false;

  *output = static_cast<u16>(value);
  return true;
}

bool TryParse(const std::string& str, u32* const output)
{
  u64 value;
  if (!TryParse(str, &value))
    return false;

  if (value >= 0x100000000ull && value <= 0xFFFFFFFF00000000ull)
    return false;

  *output = static_cast<u32>(value);
  return true;
}

bool TryParse(const std::string& str, u64* const output)
{
  char* end_ptr = nullptr;

  // Set errno to a clean slate
  errno = 0;

  u64 value = strtoull(str.c_str(), &end_ptr, 0);

  if (end_ptr == nullptr || *end_ptr != '\0')
    return false;

  if (errno == ERANGE)
    return false;

  *output = value;
  return true;
}

bool TryParse(const std::string& str, bool* const output)
{
  float value;
  const bool is_valid_float = TryParse(str, &value);
  if ((is_valid_float && value == 1) || !strcasecmp("true", str.c_str()))
    *output = true;
  else if ((is_valid_float && value == 0) || !strcasecmp("false", str.c_str()))
    *output = false;
  else
    return false;

  return true;
}

std::string StringFromBool(bool value)
{
  return value ? "True" : "False";
}

bool SplitPath(const std::string& full_path, std::string* _pPath, std::string* _pFilename,
               std::string* _pExtension)
{
  if (full_path.empty())
    return false;

  size_t dir_end = full_path.find_last_of("/"
// Windows needs the : included for something like just "C:" to be considered a directory
#ifdef _WIN32
                                          ":"
#endif
  );
  if (std::string::npos == dir_end)
    dir_end = 0;
  else
    dir_end += 1;

  size_t fname_end = full_path.rfind('.');
  if (fname_end < dir_end || std::string::npos == fname_end)
    fname_end = full_path.size();

  if (_pPath)
    *_pPath = full_path.substr(0, dir_end);

  if (_pFilename)
    *_pFilename = full_path.substr(dir_end, fname_end - dir_end);

  if (_pExtension)
    *_pExtension = full_path.substr(fname_end);

  return true;
}

void BuildCompleteFilename(std::string& _CompleteFilename, const std::string& _Path,
                           const std::string& _Filename)
{
  _CompleteFilename = _Path;

  // check for seperator
  if (DIR_SEP_CHR != *_CompleteFilename.rbegin())
    _CompleteFilename += DIR_SEP_CHR;

  // add the filename
  _CompleteFilename += _Filename;
}

std::vector<std::string> SplitString(const std::string& str, const char delim)
{
  std::istringstream iss(str);
  std::vector<std::string> output(1);

  while (std::getline(iss, *output.rbegin(), delim))
    output.push_back("");

  output.pop_back();
  return output;
}

std::string JoinStrings(const std::vector<std::string>& strings, const std::string& delimiter)
{
  // Check if we can return early, just for speed
  if (strings.empty())
    return "";

  std::stringstream res;
  std::copy(strings.begin(), strings.end(),
            std::ostream_iterator<std::string>(res, delimiter.c_str()));

  // Drop the trailing delimiter.
  std::string joined = res.str();
  return joined.substr(0, joined.length() - delimiter.length());
}

std::string TabsToSpaces(int tab_size, const std::string& in)
{
  const std::string spaces(tab_size, ' ');
  std::string out(in);

  size_t i = 0;
  while (out.npos != (i = out.find('\t')))
    out.replace(i, 1, spaces);

  return out;
}

std::string ReplaceAll(std::string result, const std::string& src, const std::string& dest)
{
  size_t pos = 0;

  if (src == dest)
    return result;

  while ((pos = result.find(src, pos)) != std::string::npos)
  {
    result.replace(pos, src.size(), dest);
    pos += dest.length();
  }

  return result;
}

bool StringBeginsWith(const std::string& str, const std::string& begin)
{
  return str.size() >= begin.size() && std::equal(begin.begin(), begin.end(), str.begin());
}

bool StringEndsWith(const std::string& str, const std::string& end)
{
  return str.size() >= end.size() && std::equal(end.rbegin(), end.rend(), str.rbegin());
}

void StringPopBackIf(std::string* s, char c)
{
  if (!s->empty() && s->back() == c)
    s->pop_back();
}

#ifdef _WIN32

std::wstring CPToUTF16(u32 code_page, const std::string& input)
{
  auto const size =
      MultiByteToWideChar(code_page, 0, input.data(), static_cast<int>(input.size()), nullptr, 0);

  std::wstring output;
  output.resize(size);

  if (size == 0 ||
      size != MultiByteToWideChar(code_page, 0, input.data(), static_cast<int>(input.size()),
                                  &output[0], static_cast<int>(output.size())))
  {
    output.clear();
  }

  return output;
}

std::string UTF16ToCP(u32 code_page, const std::wstring& input)
{
  auto const size = WideCharToMultiByte(code_page, 0, input.data(), static_cast<int>(input.size()),
                                        nullptr, 0, nullptr, false);

  std::string output;
  output.resize(size);

  if (size == 0 ||
      size != WideCharToMultiByte(code_page, 0, input.data(), static_cast<int>(input.size()),
                                  &output[0], static_cast<int>(output.size()), nullptr, false))
  {
    const DWORD error_code = GetLastError();
    ERROR_LOG(COMMON, "WideCharToMultiByte Error in String '%s': %lu", input.c_str(), error_code);
    output.clear();
  }
  return output;
}

std::wstring UTF8ToUTF16(const std::string& input)
{
  return CPToUTF16(CP_UTF8, input);
}

std::string UTF16ToUTF8(const std::wstring& input)
{
  return UTF16ToCP(CP_UTF8, input);
}

std::string SHIFTJISToUTF8(const std::string& input)
{
  return UTF16ToUTF8(CPToUTF16(CODEPAGE_SHIFT_JIS, input));
}

std::string UTF8ToSHIFTJIS(const std::string& input)
{
  return UTF16ToCP(CODEPAGE_SHIFT_JIS, UTF8ToUTF16(input));
}

std::string CP1252ToUTF8(const std::string& input)
{
  return UTF16ToUTF8(CPToUTF16(CODEPAGE_WINDOWS_1252, input));
}

std::string UTF16BEToUTF8(const char16_t* str, size_t max_size)
{
  const char16_t* str_end = std::find(str, str + max_size, '\0');
  std::wstring result(static_cast<size_t>(str_end - str), '\0');
  std::transform(str, str_end, result.begin(), static_cast<u16 (&)(u16)>(Common::swap16));
  return UTF16ToUTF8(result);
}

#else

template <typename T>
std::string CodeTo(const char* tocode, const char* fromcode, const std::basic_string<T>& input)
{
  std::string result;

  iconv_t const conv_desc = iconv_open(tocode, fromcode);
  if ((iconv_t)-1 == conv_desc)
  {
    ERROR_LOG(COMMON, "Iconv initialization failure [%s]: %s", fromcode, strerror(errno));
  }
  else
  {
    size_t const in_bytes = sizeof(T) * input.size();
    size_t const out_buffer_size = 4 * in_bytes;

    std::string out_buffer;
    out_buffer.resize(out_buffer_size);

    auto src_buffer = &input[0];
    size_t src_bytes = in_bytes;
    auto dst_buffer = &out_buffer[0];
    size_t dst_bytes = out_buffer.size();

    while (src_bytes != 0)
    {
      size_t const iconv_result =
          iconv(conv_desc, (char**)(&src_buffer), &src_bytes, &dst_buffer, &dst_bytes);

      if ((size_t)-1 == iconv_result)
      {
        if (EILSEQ == errno || EINVAL == errno)
        {
          // Try to skip the bad character
          if (src_bytes != 0)
          {
            --src_bytes;
            ++src_buffer;
          }
        }
        else
        {
          ERROR_LOG(COMMON, "iconv failure [%s]: %s", fromcode, strerror(errno));
          break;
        }
      }
    }

    out_buffer.resize(out_buffer_size - dst_bytes);
    out_buffer.swap(result);

    iconv_close(conv_desc);
  }

  return result;
}

template <typename T>
std::string CodeToUTF8(const char* fromcode, const std::basic_string<T>& input)
{
  return CodeTo("UTF-8", fromcode, input);
}

std::string CP1252ToUTF8(const std::string& input)
{
  // return CodeToUTF8("CP1252//TRANSLIT", input);
  // return CodeToUTF8("CP1252//IGNORE", input);
  return CodeToUTF8("CP1252", input);
}

std::string SHIFTJISToUTF8(const std::string& input)
{
  // return CodeToUTF8("CP932", input);
  return CodeToUTF8("SJIS", input);
}

std::string UTF8ToSHIFTJIS(const std::string& input)
{
  return CodeTo("SJIS", "UTF-8", input);
}

std::string UTF16ToUTF8(const std::wstring& input)
{
  std::wstring_convert<std::codecvt_utf8<wchar_t>, wchar_t> converter;
  return converter.to_bytes(input);
}

std::string UTF16BEToUTF8(const char16_t* str, size_t max_size)
{
  const char16_t* str_end = std::find(str, str + max_size, '\0');
  return CodeToUTF8("UTF-16BE", std::u16string(str, static_cast<size_t>(str_end - str)));
}

#endif