~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

 */

#ifndef DRIZZLED_FUNCTION_TIME_DATE_H

#define DRIZZLED_FUNCTION_TIME_DATE_H

#include "drizzled/function/func.h"

#include "drizzled/function/str/strfunc.h"

/* forward declarations */

namespace drizzled {class Date;}

/* A function which evaluates to a Date */

class Item_date :public Item_func

{

public:

  using Item_func::tmp_table_field;

  Item_date() :Item_func() {}

  Item_date(Item *a) :Item_func(a) {}

  enum Item_result result_type () const { return STRING_RESULT; }

  enum_field_types field_type() const { return DRIZZLE_TYPE_DATE; }

  String *val_str(String *str);

  int64_t val_int();

  double val_real() { return val_real_from_decimal(); }

  const char *func_name() const { return "date"; }

  void fix_length_and_dec()

  {

    collation.set(&my_charset_bin);

    decimals=0;

    max_length=MAX_DATE_WIDTH*MY_CHARSET_BIN_MB_MAXLEN;

  }

  /**

   * All functions which inherit from Item_date must implement

   * their own get_temporal() method, which takes a supplied

   * drizzled::Date reference and populates it with a correct

   * date based on the semantics of the function.

   *

   * Returns whether the function was able to correctly fill

   * the supplied date temporal with a proper date.

   *

   * @param Reference to a drizzled::Date to populate

   */

  virtual bool get_temporal(drizzled::Date &temporal)= 0;

  Field *tmp_table_field(Table *table)

  {

    return tmp_table_field_from_field_type(table, 0);

  }

  bool result_as_int64_t() { return true; }

  my_decimal *val_decimal(my_decimal *decimal_value)

  {

    assert(fixed == 1);

    return  val_decimal_from_date(decimal_value);

  }

  int save_in_field(Field *field,

                    bool )

  {

    return save_date_in_field(field);

  }

};

class Item_date_func :public Item_str_func

{

public:

  Item_date_func() :Item_str_func() {}

  Item_date_func(Item *a) :Item_str_func(a) {}

  Item_date_func(Item *a,Item *b) :Item_str_func(a,b) {}

  Item_date_func(Item *a,Item *b, Item *c) :Item_str_func(a,b,c) {}

  enum_field_types field_type() const { return DRIZZLE_TYPE_DATETIME; }

  using Item_func::tmp_table_field;

  Field *tmp_table_field(Table *table)

  {

    return tmp_table_field_from_field_type(table, 0);

  }

  bool result_as_int64_t() { return true; }

  double val_real() { return (double) val_int(); }

  my_decimal *val_decimal(my_decimal *decimal_value)

  {

    assert(fixed == 1);

    return  val_decimal_from_date(decimal_value);

  }

  int save_in_field(Field *field,

                    bool )

  {

    return save_date_in_field(field);

  }

};

#endif /* DRIZZLED_FUNCTION_TIME_DATE_H */