mapnik/include/mapnik/sql_utils.hpp

/*****************************************************************************
 * 
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2011 Artem Pavlenko
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *****************************************************************************/

#ifndef MAPNIK_SQL_UTILS_HPP
#define MAPNIK_SQL_UTILS_HPP

// boost
#include <boost/algorithm/string.hpp>
#include <boost/scoped_array.hpp>

namespace mapnik { namespace sql_utils {

inline std::string unquote_double(const std::string& sql)
{
    std::string table_name = boost::algorithm::to_lower_copy(sql);  
    boost::algorithm::trim_if(table_name,boost::algorithm::is_any_of("\""));
    return table_name;
}

inline std::string unquote(const std::string& sql)
{
    std::string table_name = boost::algorithm::to_lower_copy(sql);  
    boost::algorithm::trim_if(table_name,boost::algorithm::is_any_of("\"\'"));
    return table_name;
}

inline void quote_attr(std::ostringstream& s, const std::string& field)
{
    if (boost::algorithm::icontains(field,".")) {
        std::vector<std::string> parts;
        boost::split(parts, field, boost::is_any_of("."));
        s << ",\"" << parts[0] << "\".\"" << parts[1] << "\"";
    }
    else
    {
        s << ",\"" + field + "\"";
    }
}

inline std::string table_from_sql(const std::string& sql)
{
    std::string table_name = boost::algorithm::to_lower_copy(sql);
    boost::algorithm::replace_all(table_name,"\n"," ");
   
    std::string::size_type idx = table_name.rfind(" from ");
    if (idx!=std::string::npos)
    {
        idx = table_name.find_first_not_of(" ",idx+5);
        if (idx != std::string::npos)
        {
            table_name=table_name.substr(idx);
        }
        idx = table_name.find_first_of(" )");
        if (idx != std::string::npos)
        {
            table_name = table_name.substr(0,idx);
        }
    }
    return table_name;
}

inline std::string numeric2string(const char* buf)
{
   int16_t ndigits = int2net(buf);
   int16_t weight  = int2net(buf+2);
   int16_t sign    = int2net(buf+4);
   int16_t dscale  = int2net(buf+6);
   
   boost::scoped_array<int16_t> digits(new int16_t[ndigits]); 
   for (int n=0; n < ndigits ;++n)
   {
      digits[n] = int2net(buf+8+n*2);
   }
   
   std::ostringstream ss;
   
   if (sign == 0x4000) ss << "-";
   
   int i = std::max(weight,int16_t(0));
   int d = 0;

   // Each numeric "digit" is actually a value between 0000 and 9999 stored in a 16 bit field.
   // For example, the number 1234567809990001 is stored as four digits: [1234] [5678] [999] [1].
   // Note that the last two digits show that the leading 0's are lost when the number is split.
   // We must be careful to re-insert these 0's when building the string.

   while ( i >= 0)
   {
      if (i <= weight && d < ndigits)
      {
         // All digits after the first must be padded to make the field 4 characters long
         if (d != 0) 
         {
#ifdef _WINDOWS
             int dig = digits[d];
             if (dig < 10)
             {
                 ss << "000"; // 0000 - 0009
             }
             else if (dig < 100)
             {
                 ss << "00";  // 0010 - 0099
             }
             else
             {
                 ss << "0";   // 0100 - 0999;
             }
#else
             switch(digits[d])
             {
                 case 0 ... 9:
                     ss << "000"; // 0000 - 0009
                     break;
                 case 10 ... 99:
                     ss << "00";  // 0010 - 0099
                     break;
                 case 100 ... 999:
                     ss << "0";   // 0100 - 0999
                     break;
             }
#endif
         }
         ss << digits[d++];
      }
      else
      {
         if (d == 0)
             ss <<  "0";
         else
             ss <<  "0000";
      }
      
      i--;
   }
   if (dscale > 0)
   {
      ss << '.';
      // dscale counts the number of decimal digits following the point, not the numeric digits
      while (dscale > 0)
      {
         int value;
         if (i <= weight && d < ndigits)
              value = digits[d++];
         else
              value = 0;

         // Output up to 4 decimal digits for this value
         if (dscale > 0) {
              ss << (value / 1000);
              value %= 1000;
              dscale--;
         }
         if (dscale > 0) {
              ss << (value / 100);
              value %= 100;
              dscale--;
         }
         if (dscale > 0) {
              ss << (value / 10);
              value %= 10;
              dscale--;
         }
         if (dscale > 0) {
              ss << value;
              dscale--;
         }

         i--;
      }
   }
   return ss.str();
}
}

}

#endif // MAPNIK_SQL_UTILS_HPP