/* Copyright (C) 2014 InfiniDB, Inc.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; version 2 of
   the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

/*******************************************************************************
* $Id: we_blockop.cpp 4500 2013-01-31 20:25:42Z dhall $
*
*******************************************************************************/
/** @file */

#include <stdio.h>
#include <string.h>

#include "joblisttypes.h"
#include "mcs_datatype.h"

#include "we_blockop.h"

#include "we_config.h"
#include "we_brm.h"
#include "we_convertor.h"

using namespace execplan;

namespace WriteEngine
{

/**
 * Constructor
 */
BlockOp::BlockOp(): m_typeHandler(nullptr)
{}

/**
 * Default Destructor
 */
BlockOp::~BlockOp()
{}

/***********************************************************
 * DESCRIPTION:
 *    Calculate the location of Row ID
 * PARAMETERS:
 *    rowId - row id
 *    epb - entry per block
 *    width - width per column record
 * RETURN:
 *    fbo - File block offset
 *    bio - Block internal offset
 *    true if success, false otherwise
 ***********************************************************/
bool BlockOp::calculateRowId(
    RID rowId, const int epb, const int width, int& fbo, int& bio ) const
{
    if ( std::numeric_limits<WriteEngine::RID>::max() == rowId )
        return false;

    fbo = (int)( rowId / epb );
    bio = ( rowId & ( epb - 1 )) * width;

    return true;
}

/***********************************************************
 * DESCRIPTION:
 *    Get the value that represents empty row
 * PARAMETERS:
 *    colDataType - data type
 *    width - data width in byte
 * RETURN:
 *    emptyVal - the value of empty row
 ***********************************************************/
const uint8_t* BlockOp::getEmptyRowValue(
    const CalpontSystemCatalog::ColDataType colDataType,
    const int width) const
{
    auto attrs = datatypes::SystemCatalog::TypeAttributesStd(width, 0, -1);
    // Bulk operation runtime should have m_typeHandler nullptr calling this
    // Non-bulk operations runtime branch
    if (m_typeHandler)
        return m_typeHandler->getEmptyValueForType(attrs);

    // Bulk operation branch
    auto* typeHandler = datatypes::TypeHandler::find(colDataType,
                                                     attrs);
    return typeHandler->getEmptyValueForType(attrs);
}

/***********************************************************
 * DESCRIPTION:
 *    Get the correct width for a row
 * PARAMETERS:
 *    colDataType - data type
 *    width - data width in byte
 * RETURN:
 *    emptyVal - the value of empty row
 ***********************************************************/
int BlockOp::getCorrectRowWidth(
    const CalpontSystemCatalog::ColDataType colDataType, const int width ) const
{
    return Convertor::getCorrectRowWidth(colDataType, width);
}

/***********************************************************
 * DESCRIPTION:
 *    Get row id
 * PARAMETERS:
 *    fbo - file block offset
 *    bio - block internal offset
 *    bbo - byte internal offset
 * RETURN:
 *    row id
 ***********************************************************/
RID BlockOp::getRowId(
    const long fbo, const int width, const int rowPos
    /*const int bio, const int bbo*/ ) const
{
//      return fbo*BYTE_PER_BLOCK*ROW_PER_BYTE + bio*ROW_PER_BYTE + bbo;
    return (BYTE_PER_BLOCK / width) * fbo + rowPos;
}

/***********************************************************
 * DESCRIPTION:
 *    Get buffer value
 * PARAMETERS:
 *    buf - buffer
 *    width - data width in byte
 * RETURN:
 *    val - buffer value
 ***********************************************************/
void BlockOp::readBufValue(
    const unsigned char* buf, void* val, const short width ) const
{
    memcpy( val, buf, width );
}

/***********************************************************
 * DESCRIPTION:
 *    Reset a buffer
 * PARAMETERS:
 *    buf - buffer
 *    bufSize - buffer size
 * RETURN:
 *    none
 ***********************************************************/
void BlockOp::resetBuf(  unsigned char* buf, const int bufSize ) const
{
    memset( buf, 0, bufSize );
}

/***********************************************************
 * DESCRIPTION:
 *    Fill buffer with empty values
 * PARAMETERS:
 *    buf - buffer
 *    bufSize - buffer size
 *    emptyVal - empty value
 *    width - type width
 * RETURN:
 *    none
 ***********************************************************/
/* static */
void BlockOp::setEmptyBuf(
    unsigned char* buf,
    const int bufSize,
    const uint8_t* emptyVal,
    const int width )
{
    const int ARRAY_COUNT     = 128;
    const int NBYTES_IN_ARRAY = width * ARRAY_COUNT;
    //unsigned char emptyValArray[NBYTES_IN_ARRAY];
    unsigned char* emptyValArray = (unsigned char*)alloca(NBYTES_IN_ARRAY);

    // Optimize buffer initialization by constructing and copying in an array
    // instead of individual values.  This reduces the number of calls to
    // memcpy().
     
    for(uint8_t* pos = emptyValArray, * end = pos + NBYTES_IN_ARRAY; pos < end; pos += width) //FIXME for no loop
    {
        memcpy(pos, emptyVal, width);
    }

    int countFull128 = (bufSize / width) / ARRAY_COUNT;
    int countRemain  = (bufSize / width) % ARRAY_COUNT;

    // Copy in the 128 element array into "buf" as many times as needed
    if (countFull128 > 0)
    {
        for ( int i = 0; i < countFull128; i++ )
            memcpy( buf + (i * (NBYTES_IN_ARRAY)),
                    emptyValArray,
                    NBYTES_IN_ARRAY );
    }

    // Initialize the remainder of "buf" that is leftover
    if (countRemain > 0)
    {
        memcpy( buf + (countFull128 * NBYTES_IN_ARRAY),
                emptyValArray,
                width * countRemain );
    }
}

/***********************************************************
 * DESCRIPTION:
 *    Set a value in a buffer
 * PARAMETERS:
 *    buf - buffer
 *    val - buffer value
 *    width - data width in byte
 * RETURN:
 *    none
 ***********************************************************/
void BlockOp::writeBufValue(
    unsigned char* buf, const void* val, const size_t width, const bool clear ) const
{
    if ( clear )
        memset( buf, 0, width );

    memcpy( buf, val, width );
}

void BlockOp::findTypeHandler(const int colWidth,
                              const execplan::CalpontSystemCatalog::ColDataType colDataType)

{
    auto attrs = datatypes::SystemCatalog::TypeAttributesStd(colWidth,
                                                             0,
                                                             -1);
    m_typeHandler = datatypes::TypeHandler::find(colDataType,
                                                 attrs);
}

} //end of namespace