/* 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: func_hex.cpp 3923 2013-06-19 21:43:06Z bwilkinson $
*
*
****************************************************************************/

#include <cstdlib>
#include <string>
#include <sstream>
#include <limits>
using namespace std;

#include <boost/scoped_array.hpp>
using namespace boost;

#include "functor_str.h"
#include "functioncolumn.h"
#include "rowgroup.h"
using namespace execplan;

#include "funchelpers.h"

namespace
{
char digit_upper[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";

void octet2hex(char* to, const char* str, uint32_t len)
{
    const char* str_end = str + len;

    for (; str != str_end; ++str)
    {
        *to++ = digit_upper[((uint8_t) * str) >> 4];
        *to++ = digit_upper[((uint8_t) * str) & 0x0F];
    }

    *to = '\0';
}
}

namespace funcexp
{
CalpontSystemCatalog::ColType Func_hex::operationType( FunctionParm& fp, CalpontSystemCatalog::ColType& resultType )
{
    return resultType;
}

string Func_hex::getStrVal(rowgroup::Row& row,
                           FunctionParm& parm,
                           bool& isNull,
                           CalpontSystemCatalog::ColType& ct)
{
    string retval;
    uint64_t dec;
    char ans[65];

    switch (parm[0]->data()->resultType().colDataType)
    {
        case CalpontSystemCatalog::CHAR:
        case CalpontSystemCatalog::TEXT:
        case CalpontSystemCatalog::VARCHAR:
        case CalpontSystemCatalog::DATETIME:
        case CalpontSystemCatalog::DATE:
        {
            const string& arg = parm[0]->data()->getStrVal(row, isNull);
            scoped_array<char> hexPtr(new char[strlen(arg.c_str()) * 2 + 1]);
            octet2hex(hexPtr.get(), arg.c_str(), strlen(arg.c_str()));
            return string(hexPtr.get(), strlen(arg.c_str()) * 2);
        }

        case CalpontSystemCatalog::DOUBLE:
        case CalpontSystemCatalog::FLOAT:
        case CalpontSystemCatalog::DECIMAL:
        {
            /* Return hex of unsigned longlong value */
            double val = parm[0]->data()->getDoubleVal(row, isNull);

            if ((val <= (double) numeric_limits<int64_t>::min()) ||
                    (val >= (double) numeric_limits<int64_t>::max()))
                dec =  ~(int64_t) 0;
            else
                dec = (uint64_t) (val + (val > 0 ? 0.5 : -0.5));

            retval = helpers::convNumToStr(dec, ans, 16);
            break;
        }

        case CalpontSystemCatalog::VARBINARY:
        case CalpontSystemCatalog::BLOB:
        {
            const string& arg = parm[0]->data()->getStrVal(row, isNull);
            uint64_t hexLen = arg.size() * 2;
            scoped_array<char> hexPtr(new char[hexLen + 1]);  // "+ 1" for the last \0
            octet2hex(hexPtr.get(), arg.data(), arg.size());
            return string(hexPtr.get(), hexLen);
        }

        default:
        {
            dec = (uint64_t)parm[0]->data()->getIntVal(row, isNull);
            retval = helpers::convNumToStr(dec, ans, 16);

            if (retval.length() > (uint32_t)ct.colWidth)
                retval = retval.substr(retval.length() - ct.colWidth, ct.colWidth);
        }
    }

    return retval;
}


} // namespace funcexp
// vim:ts=4 sw=4: