/******************************************************************************

* Copyright (c) 2011, Michael P. Gerlek (mpg@flaxen.com)

*

* All rights reserved.

*

* Redistribution and use in source and binary forms, with or without

* modification, are permitted provided that the following

* conditions are met:

*

* * Redistributions of source code must retain the above copyright

* notice, this list of conditions and the following disclaimer.

* * Redistributions in binary form must reproduce the above copyright

* notice, this list of conditions and the following disclaimer in

* the documentation and/or other materials provided

* with the distribution.

* * Neither the name of Hobu, Inc. or Flaxen Geo Consulting nor the

* names of its contributors may be used to endorse or promote

* products derived from this software without specific prior

* written permission.

*

* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS

* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE

* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,

* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,

* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS

* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

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* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY

* OF SUCH DAMAGE.

****************************************************************************/

#include <pdal/StageIterator.hpp>

#include <algorithm> // for std::min/max

#include <pdal/NullPointBuffer.hpp>

#include <pdal/Stage.hpp>

namespace pdal

{

static boost::uint32_t s_defaultChunkSize = 65536;

//---------------------------------------------------------------------------

//

// StageIterator

//

//---------------------------------------------------------------------------

StageIterator::StageIterator(PointBuffer& buffer)

: m_index(0)

, m_buffer(buffer)

, m_chunkSize(s_defaultChunkSize)

, m_readBeginPerformed(false)

, m_readBufferBeginPerformed(false)

{}

boost::uint64_t StageIterator::getIndex() const

{

return m_index;

}

void StageIterator::setChunkSize(boost::uint32_t size)

{

m_chunkSize = size;

}

boost::uint32_t StageIterator::getChunkSize() const

{

return m_chunkSize;

}

boost::uint32_t StageIterator::read(PointBuffer& buffer)

{

readBegin();

readBufferBegin(buffer);

boost::uint32_t numRead = readBuffer(buffer);

readBufferEnd(buffer);

readEnd();

return numRead;

}

void StageIterator::readBegin()

{

if (m_readBeginPerformed)

{

throw pdal_error("readBegin called without corresponding readEnd");

}

m_readBeginPerformed = false;

readBeginImpl();

m_readBeginPerformed = true;

}

void StageIterator::readBufferBegin(PointBuffer& buffer)

{

if (!m_readBeginPerformed)

{

throw pdal_error("readBufferBegin called without corresponding "

"readBegin");

}

if (m_readBufferBeginPerformed)

{

throw pdal_error("readBufferBegin called without corresponding "

"readBufferEnd");

}

m_readBufferBeginPerformed = false;

readBufferBeginImpl(buffer);

m_readBufferBeginPerformed = true;

}

boost::uint32_t StageIterator::readBuffer(PointBuffer& buffer)

{

if (!m_readBufferBeginPerformed)

{

throw pdal_error("readBuffer called without corresponding "

"readBufferBegin");

}

boost::uint32_t numRead = readBufferImpl(buffer);

m_index += numRead;

return numRead;

}

void StageIterator::readBufferEnd(PointBuffer& buffer)

{

if (!m_readBufferBeginPerformed)

{

throw pdal_error("readBufferEnd called without corresponding "

"readBufferBegin");

}

readBufferEndImpl(buffer);

m_readBufferBeginPerformed = false;

}

void StageIterator::readEnd()

{

if (m_readBufferBeginPerformed)

{

throw pdal_error("readEnd called without corresponding readBufferEnd");

}

if (!m_readBeginPerformed)

{

throw pdal_error("readEnd called without corresponding readBegin");

}

readEndImpl();

m_readBeginPerformed = false;

}

boost::uint64_t StageIterator::skip(boost::uint64_t count)

{

uint32_t pos = m_index;

boost::uint64_t numSkipped = skipImpl(count);

m_index = pos + numSkipped;

return numSkipped;

}

boost::uint64_t StageIterator::naiveSkipImpl(boost::uint64_t count)

{

boost::uint64_t totalNumRead = 0;

// read (and discard) all the next 'count' points

// in case count is really big, we do this in blocks of size 'chunk'

while (count > 0)

{

boost::uint64_t thisCount64 =

std::min<boost::uint64_t>(getChunkSize(), count);

// getChunkSize is a uint32, so this cast is safe

boost::uint32_t thisCount =

static_cast<boost::uint32_t>(thisCount64);

NullPointBuffer junk;

boost::uint32_t numRead = read(junk);

if (numRead == 0)

break; // end of file or something

count -= numRead;

totalNumRead += numRead;

}

return totalNumRead;

}

//---------------------------------------------------------------------------

//

// StageSequentialIterator

//

//---------------------------------------------------------------------------

StageSequentialIterator::StageSequentialIterator(PointBuffer& buffer)

: StageIterator(buffer)

{}

StageSequentialIterator::~StageSequentialIterator()

{}

bool StageSequentialIterator::atEnd() const

{

return atEndImpl();

}

//---------------------------------------------------------------------------

//

// StageRandomIterator

//

//---------------------------------------------------------------------------

StageRandomIterator::StageRandomIterator(PointBuffer& buffer)

: StageIterator(buffer)

{}

StageRandomIterator::~StageRandomIterator()

{}

boost::uint64_t StageRandomIterator::seek(boost::uint64_t position)

{

m_index = seekImpl(position);

return m_index;

}

boost::uint64_t StageRandomIterator::skipImpl(boost::uint64_t numPts)

{

uint64_t pos = m_index;

pos = seekImpl(pos + numPts);

return (pos - numPts);

}

} // namespace pdal