<?php
/**
 * A primary key definition, usually attached to a {@link PGBBaseTable}.
 * 
 * A primary key is merely a set of fields.
 * @package Piragibe
 * @author Francisco Piragibe
 * @version 1.00
 * @copyright Copyright &copy; 2006, Francisco Piragibe
 * This file is part of The PIRAGIBE Framework.
 *
 * The PIRAGIBE Framework 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; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * The PIRAGIBE Framework 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 The PIRAGIBE Framework; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
class PGBPrimaryKey {
 
 /**
  * @var array a set of field names to use as the PK
  */
 var $m_pkdef;          // definicao da PK, como um array de nomes de campo
 /**
  * This only makes sense if the PK is a single, numeric field.
  * 
  * <b>ATTENTION:</b> it defaults to YES!!
  * @var boolean should the PK be generated "automagically" ? 
  */
 var $m_pkauto;         // indica se a PK e gerada automaticamente pela base de dados ou nao
 //  ATENCAO!! O DEFAULT E SIM!!

 /**
  * Standard constructor.
  * @param array $pDef array of field names to use as the PK
  * @param boolean $pAuto should the PK be auto generated ?
  */
 function PGBPrimaryKey( $pDef, $pAuto = true ) {
     $this->m_pkdef     = $pDef;
     $this->m_pkauto    = $pAuto;
 }
 
 /**
  * Getter for the array of PK fields.
  * @return array the set of fields that make up the PK
  */
 function getDefinition() {
 // retorna o array corrente que define a PK
     reset( $this->m_pkdef );
     return $this->m_pkdef;
 }
 
 /**
  * Is the given field name part of the PK?
  * @return boolean true or false, depending on the answer
  * @param string $pNome the field name
  */
 function isInPk( $pNome ) {
 // verifica se o campo cujo nome e pNome esta na PK, e retorna TRUE ou FAPGBE, dependendo
 // do caso
     $resp = false;
     reset( $this->m_pkdef );
     while( list( $k, $c ) = each( $this->m_pkdef ) ) {
         if ( $c == $pNome ) {
             $resp = true;
             break;
         }
     }
     return $resp;
 }
     
 /**
  * Getter for the auto generated flag.
  * @return boolean should the PK be auto generated ?
  */
 function getPkAuto() {
 // retorna o flag de PK gerada automaticamente pelo SGBD
     return $this->m_pkauto;
 }

 /**
  * Setter for the auto generated flag.
  * @param boolean $pka the auto generated flag
  */
 function setPkAuto( $pka ) {
 // seta o flag de PK automatica
     $this->m_pkauto = $pka;
 }
    
}
?>