~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2008 Sun Microsystems

 *

 *  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 St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#include "config.h"

#include "format.h"

#include <limits>

using namespace std;

namespace drizzled

{

/**

  Change a number to format '3,333,333,333.000'.

  This should be 'internationalized' sometimes.

*/

const int FORMAT_MAX_DECIMALS= 30;

void Item_func_format::fix_length_and_dec()

{

  collation.set(default_charset());

  uint32_t char_length= args[0]->max_length/args[0]->collation.collation->mbmaxlen;

  max_length= ((char_length + (char_length-args[0]->decimals)/3) *

               collation.collation->mbmaxlen);

}

/**

  @todo

  This needs to be fixed for multi-byte character set where numbers

  are stored in more than one byte

*/

String *Item_func_format::val_str(String *str)

{

  uint32_t length;

  uint32_t str_length;

  /* Number of decimal digits */

  int dec;

  /* Number of characters used to represent the decimals, including '.' */

  uint32_t dec_length;

  int diff;

  assert(fixed == 1);

  dec= (int) args[1]->val_int();

  if (args[1]->null_value)

  {

    null_value=1;

    return NULL;

  }

  dec= set_zone(dec, 0, FORMAT_MAX_DECIMALS);

  dec_length= dec ? dec+1 : 0;

  null_value=0;

  if (args[0]->result_type() == DECIMAL_RESULT ||

      args[0]->result_type() == INT_RESULT)

  {

    my_decimal dec_val, rnd_dec, *res;

    res= args[0]->val_decimal(&dec_val);

    if ((null_value=args[0]->null_value))

      return 0;

    my_decimal_round(E_DEC_FATAL_ERROR, res, dec, false, &rnd_dec);

    my_decimal2string(E_DEC_FATAL_ERROR, &rnd_dec, 0, 0, 0, str);

    str_length= str->length();

    if (rnd_dec.sign())

      str_length--;

  }

  else

  {

    double nr= args[0]->val_real();

    if ((null_value=args[0]->null_value))

      return 0;

    nr= my_double_round(nr, (int64_t) dec, false, false);

    /* Here default_charset() is right as this is not an automatic conversion */

    str->set_real(nr, dec, default_charset());

    if (nr == numeric_limits<double>::quiet_NaN())

      return str;

    str_length=str->length();

    if (nr < 0)

      str_length--;				// Don't count sign

  }

  /* We need this test to handle 'nan' values */

  if (str_length >= dec_length+4)

  {

    char *tmp,*pos;

    length= str->length()+(diff=((int)(str_length- dec_length-1))/3);

    str= copy_if_not_alloced(&tmp_str,str,length);

    str->length(length);

    tmp= (char*) str->ptr()+length - dec_length-1;

    for (pos= (char*) str->ptr()+length-1; pos != tmp; pos--)

      pos[0]= pos[-diff];

    while (diff)

    {

      *pos= *(pos - diff);

      pos--;

      *pos= *(pos - diff);

      pos--;

      *pos= *(pos - diff);

      pos--;

      pos[0]=',';

      pos--;

      diff--;

    }

  }

  return str;

}

void Item_func_format::print(String *str, enum_query_type query_type)

{

  str->append(STRING_WITH_LEN("format("));

  args[0]->print(str, query_type);

  str->append(',');

  args[1]->print(str, query_type);

  str->append(')');

}

} /* namespace drizzled */