/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/*

 * This file is part of the libpagemaker project.

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 */

#include "libpagemaker_utils.h"

#include <cassert>

#include <cstdarg>

namespace libpagemaker

{

namespace

{

void checkStream(const RVNGInputStreamPtr &input)

{

  if (!input || input->isEnd())

    throw EndOfStreamException();

}

struct SeekFailedException : public PMDStreamException {};

}

#ifdef DEBUG

void debugPrint(const char *const format, ...)

{

  va_list args;

  va_start(args, format);

  std::vfprintf(stderr, format, args);

  va_end(args);

}

#endif

uint8_t readU8(const RVNGInputStreamPtr &input, bool /* bigEndian */)

{

  checkStream(input);

  unsigned long numBytesRead;

  uint8_t const *p = input->read(sizeof(uint8_t), numBytesRead);

  if (p && numBytesRead == sizeof(uint8_t))

    return *(uint8_t const *)(p);

  throw EndOfStreamException();

}

int8_t readS8(const RVNGInputStreamPtr &input, bool /* bigEndian */)

{

  return static_cast<int8_t>(readU8(input));

}

uint16_t readU16(const RVNGInputStreamPtr &input, bool bigEndian)

{

  checkStream(input);

  unsigned long numBytesRead;

  uint8_t const *p = input->read(sizeof(uint16_t), numBytesRead);

  if (p && numBytesRead == sizeof(uint16_t))

  {

    if (bigEndian)

      return static_cast<uint16_t>((uint16_t)p[1]|((uint16_t)p[0]<<8));

    return static_cast<uint16_t>((uint16_t)p[0]|((uint16_t)p[1]<<8));

  }

  throw EndOfStreamException();

}

int16_t readS16(const RVNGInputStreamPtr &input, const bool bigEndian)

{

  return static_cast<int16_t>(readU16(input, bigEndian));

}

uint32_t readU32(const RVNGInputStreamPtr &input, bool bigEndian)

{

  checkStream(input);

  unsigned long numBytesRead;

  uint8_t const *p = input->read(sizeof(uint32_t), numBytesRead);

  if (p && numBytesRead == sizeof(uint32_t))

  {

    if (bigEndian)

      return (uint32_t)p[3]|((uint32_t)p[2]<<8)|((uint32_t)p[1]<<16)|((uint32_t)p[0]<<24);

    return (uint32_t)p[0]|((uint32_t)p[1]<<8)|((uint32_t)p[2]<<16)|((uint32_t)p[3]<<24);

  }

  throw EndOfStreamException();

}

int32_t readS32(const RVNGInputStreamPtr &input, const bool bigEndian)

{

  return static_cast<int32_t>(readU32(input, bigEndian));

}

uint64_t readU64(const RVNGInputStreamPtr &input, bool bigEndian)

{

  checkStream(input);

  unsigned long numBytesRead;

  uint8_t const *p = input->read(sizeof(uint64_t), numBytesRead);

  if (p && numBytesRead == sizeof(uint64_t))

  {

    if (bigEndian)

      return (uint64_t)p[7]|((uint64_t)p[6]<<8)|((uint64_t)p[5]<<16)|((uint64_t)p[4]<<24)|((uint64_t)p[3]<<32)|((uint64_t)p[2]<<40)|((uint64_t)p[1]<<48)|((uint64_t)p[0]<<56);

    return (uint64_t)p[0]|((uint64_t)p[1]<<8)|((uint64_t)p[2]<<16)|((uint64_t)p[3]<<24)|((uint64_t)p[4]<<32)|((uint64_t)p[5]<<40)|((uint64_t)p[6]<<48)|((uint64_t)p[7]<<56);

  }

  throw EndOfStreamException();

}

int64_t readS64(const RVNGInputStreamPtr &input, const bool bigEndian)

{

  return static_cast<int64_t>(readU64(input, bigEndian));

}

const unsigned char *readNBytes(const RVNGInputStreamPtr &input, const unsigned long numBytes)

{

  checkStream(input);

  unsigned long readBytes = 0;

  const unsigned char *const s = input->read(numBytes, readBytes);

  if (numBytes != readBytes)

    throw EndOfStreamException();

  return s;

}

void skip(const RVNGInputStreamPtr &input, unsigned long numBytes)

{

  checkStream(input);

  seekRelative(input, static_cast<long>(numBytes));

}

void seek(const RVNGInputStreamPtr &input, const unsigned long pos)

{

  if (!input)

    throw EndOfStreamException();

  if (0 != input->seek(static_cast<long>(pos), librevenge::RVNG_SEEK_SET))

    throw SeekFailedException();

}

void seekRelative(const RVNGInputStreamPtr &input, const long pos)

{

  if (!input)

    throw EndOfStreamException();

  if (0 != input->seek(pos, librevenge::RVNG_SEEK_CUR))

    throw SeekFailedException();

}

unsigned long getLength(const RVNGInputStreamPtr &input)

{

  if (!input)

    throw EndOfStreamException();

  const long orig = input->tell();

  unsigned long end = 0;

  if (0 == input->seek(0, librevenge::RVNG_SEEK_END))

    end = static_cast<unsigned long>(input->tell());

  else

  {

    // RVNG_SEEK_END does not work. Use the harder way.

    seek(input, 0);

    while (!input->isEnd())

    {

      readU8(input);

      ++end;

    }

  }

  seek(input, orig);

  return end;

}

EndOfStreamException::EndOfStreamException()

{

}

}

/* vim:set shiftwidth=2 softtabstop=2 expandtab: */