//

// UTF16Encoding.cpp

//

// Library: Foundation

// Package: Text

// Module:  UTF16Encoding

//

// Copyright (c) 2004-2007, Applied Informatics Software Engineering GmbH.

// and Contributors.

//

// SPDX-License-Identifier: BSL-1.0

//

#include "Poco/UTF16Encoding.h"

#include "Poco/ByteOrder.h"

#include "Poco/String.h"

namespace Poco {

const char* UTF16Encoding::_names[] =

{

  "UTF-16",

  "UTF16",

  nullptr

};

const TextEncoding::CharacterMap UTF16Encoding::_charMap =

{

  /* 00 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 10 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 20 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 30 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 40 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 50 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 60 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 70 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 80 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* 90 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* a0 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* b0 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* c0 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* d0 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* e0 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

  /* f0 */  -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,

};

UTF16Encoding::UTF16Encoding(ByteOrderType byteOrder)

{

  setByteOrder(byteOrder);

}

UTF16Encoding::UTF16Encoding(int byteOrderMark)

{

  setByteOrder(byteOrderMark);

}

UTF16Encoding::~UTF16Encoding()

{

}

UTF16Encoding::ByteOrderType UTF16Encoding::getByteOrder() const

{

#if defined(POCO_ARCH_BIG_ENDIAN)

  return _flipBytes ? LITTLE_ENDIAN_BYTE_ORDER : BIG_ENDIAN_BYTE_ORDER;

#else

  return _flipBytes ? BIG_ENDIAN_BYTE_ORDER : LITTLE_ENDIAN_BYTE_ORDER;

#endif

}

void UTF16Encoding::setByteOrder(ByteOrderType byteOrder)

{

#if defined(POCO_ARCH_BIG_ENDIAN)

  _flipBytes = byteOrder == LITTLE_ENDIAN_BYTE_ORDER;

#else

  _flipBytes = byteOrder == BIG_ENDIAN_BYTE_ORDER;;

#endif

}

void UTF16Encoding::setByteOrder(int byteOrderMark)

{

  _flipBytes = byteOrderMark != 0xFEFF;

}

const char* UTF16Encoding::canonicalName() const

{

  return _names[0];

}

bool UTF16Encoding::isA(const std::string& encodingName) const

{

  for (const char** name = _names; *name; ++name)

  {

    if (Poco::icompare(encodingName, *name) == 0)

      return true;

  }

  return false;

}

const TextEncoding::CharacterMap& UTF16Encoding::characterMap() const

{

  return _charMap;

}

int UTF16Encoding::convert(const unsigned char* bytes) const

{

  UInt16 uc;

  unsigned char* p = (unsigned char*) &uc;

  *p++ = *bytes++;

  *p++ = *bytes++;

  if (_flipBytes)

  {

    uc = ByteOrder::flipBytes(uc);

  }

  if (uc >= 0xd800 && uc < 0xdc00)

  {

    UInt16 uc2;

    p = (unsigned char*) &uc2;

    *p++ = *bytes++;

    *p++ = *bytes++;

    if (_flipBytes)

    {

      uc2 = ByteOrder::flipBytes(uc2);

    }

    if (uc2 >= 0xdc00 && uc2 < 0xe000)

    {

      return ((uc & 0x3ff) << 10) + (uc2 & 0x3ff) + 0x10000;

    }

    else

    {

      return -1;

    }

  }

  else

  {

    return uc;

  }

}

int UTF16Encoding::convert(int ch, unsigned char* bytes, int length) const

{

  if (ch <= 0xFFFF)

  {

    if (bytes && length >= 2)

    {

      UInt16 ch1 = _flipBytes ? ByteOrder::flipBytes((UInt16) ch) : (UInt16) ch;

      unsigned char* p = (unsigned char*) &ch1;

      *bytes++ = *p++;

      *bytes++ = *p++;

    }

    return 2;

  }

  else

  {

    if (bytes && length >= 4)

    {

      int ch1 = ch - 0x10000;

      UInt16 w1 = 0xD800 + ((ch1 >> 10) & 0x3FF);

      UInt16 w2 = 0xDC00 + (ch1 & 0x3FF);

      if (_flipBytes)

      {

        w1 = ByteOrder::flipBytes(w1);

        w2 = ByteOrder::flipBytes(w2);

      }

      unsigned char* p = (unsigned char*) &w1;

      *bytes++ = *p++;

      *bytes++ = *p++;

      p = (unsigned char*) &w2;

      *bytes++ = *p++;

      *bytes++ = *p++;

    }

    return 4;

  }

}

int UTF16Encoding::queryConvert(const unsigned char* bytes, int length) const

{

  int ret = -2;

  if (length >= 2)

  {

    UInt16 uc;

    unsigned char* p = (unsigned char*) &uc;

    *p++ = *bytes++;

    *p++ = *bytes++;

    if (_flipBytes)

    {

      uc = ByteOrder::flipBytes(uc);

    }

    if (uc >= 0xd800 && uc < 0xdc00)

    {

      if (length >= 4)

      {

        UInt16 uc2;

        p = (unsigned char*) &uc2;

        *p++ = *bytes++;

        *p++ = *bytes++;

        if (_flipBytes)

        {

          uc2 = ByteOrder::flipBytes(uc2);

        }

        if (uc2 >= 0xdc00 && uc < 0xe000)

        {

          ret = ((uc & 0x3ff) << 10) + (uc2 & 0x3ff) + 0x10000;

        }

        else

        {

          ret = -1; // Malformed sequence

        }

      }

      else

      {

        ret = -4; // surrogate pair, four bytes needed

      }

    }

    else

    {

      ret = uc;

    }

  }

  return ret;

}

int UTF16Encoding::sequenceLength(const unsigned char* bytes, int length) const

{

  int ret = -2;

  if (_flipBytes)

  {

    if (length >= 1)

    {

      unsigned char c = *bytes;

      if (c >= 0xd8 && c < 0xdc)

        ret = 4;

      else

        ret = 2;

    }

  }

  else

  {

    if (length >= 2)

    {

      UInt16 uc;

      unsigned char* p = (unsigned char*) &uc;

      *p++ = *bytes++;

      *p++ = *bytes++;

      if (uc >= 0xd800 && uc < 0xdc00)

        ret = 4;

      else

        ret = 2;

    }

  }

  return ret;

}

} // namespace Poco