source: trunk/patForms/Storage/DB.php @ 247

<?php
/**
 * patForms storage DB
 *
 * $Id$
 *
 * @package     patForms
 * @subpackage  Storage
 * @author      Stephan Schmidt <schst@php-tools.net>
 */

/**
 * needs PEAR::DB
 */
require_once 'DB.php';

/**
 * could not open storage container
 */
define( 'PATFORMS_STORAGE_ERROR_STORAGE_INVALID', 20000 );
 
/**
 * patForms storage DB
 *
 * Stores form data in a database.
 *
 * @access      protected
 * @package     patForms
 * @subpackage  Storage
 * @author      Stephan Schmidt <schst@php-tools.net>
 * @license     LGPL, see license.txt for details
 * @link        http://www.php-tools.net
 * @todo        add error management
 */
class patForms_Storage_DB extends patForms_Storage
{
   /**
    * datasource name
    *
    * @access   private
    * @var      string
    */
    var $_dsn;

   /**
    * table name
    *
    * @access   private
    * @var      string
    */
    var $_table;

   /**
    * instance of PEAR::DB
    *
    * @access   private
    * @var      object
    */
    var $_db;

   /**
    * field map
    *
    * @access   private
    * @var      string
    */
    var $_fieldMap  =   array();

   /**
    * set the dsn and table
    *
    * @access   public
    * @param    string      datasource name
    * @param    string      table
    */
    function setStorageLocation( $dsn, $table )
    {
        $this->_dsn     =   $dsn;
        $this->_table   =   $table;
    }

   /**
    * set the field map
    *
    * The field map is an associative array, that defines how
    * the form elements (key) map to fields in the
    * table (value)
    *
    * @access   public
    * @param    array       field map
    */
    function setFieldMap($fieldMap)
    {
        $this->_fieldMap = $fieldMap;
    }

   /**
    * get an entry
    *
    * This tries to find an entry in the storage container
    * that matches the current data that has been set in the
    * form and populates the form with the data of this
    * entry
    *
    * @access   public
    * @param    object patForms     patForms object that should be stored
    * @return   boolean             true on success
    */
    function loadEntry(&$form)
    {
        $values  = $form->getValues();
        $primary = $this->getPrimary($values);

        // no primary key, storage will only add entries
        if (empty($primary)) {
            return array();
        }
        
        /**
         * entry does not exists
         */
        if (!$data = $this->_entryExists($primary)) {
            return array();
        }
            
        $values = $this->_unmapFields($data);

        $form->setValues($values);
        return true;
    }

   /**
    * adds an entry to the storage
    *
    * The entry will be appended at the end of the file.
    *
    * @abstract
    * @param    object patForms     patForms object that should be stored
    * @return   boolean             true on success
    */
    function _addEntry( &$form )
    {
        $values = $form->getValues();
        
        $this->_prepareConnection();
        $values = $this->_mapFields($values);
        
        $values = array_merge($values, $this->_staticValues);
        
        $fields = array_keys($values);
        $values = array_map(array($this->_db, 'quoteSmart'), array_values($values));

        $query  = sprintf('INSERT INTO %s (%s) VALUES (%s);', 
                          $this->_table,
                          implode(',', $fields),
                          implode(',', $values)
                      );
        
        $result = $this->_db->query($query);
        
        if (PEAR::isError($result)) {
            return false;
        }
        return true;        
    }

   /**
    * updates an entry in the storage
    *
    * Implement this in the concrete storage container.
    *
    * @abstract
    * @param    object patForms     patForms object that should be stored
    * @return   boolean             true on success
    */
    function _updateEntry( &$form, $primary )
    {
        $values = $form->getValues();
        
        $this->_prepareConnection();
        $values  = $this->_mapFields($values);
        $primary = $this->_mapFields($primary);
        
        $tmp = array();
        foreach ($values as $key => $value) {
            array_push( $tmp, $key.'='.$this->_db->quoteSmart( $value ) );
        }

        $ptmp = array();
        foreach ($primary as $key => $value) {
            array_push( $ptmp, $key.'='.$this->_db->quoteSmart( $value ) );
        }

        $query = 'UPDATE '.$this->_table.' SET '.implode( ', ', $tmp ).' WHERE '.implode( ' AND ', $ptmp );
        $this->_db->query( $query );
        return true;        
    }

   /**
    * check, whether an entry exists
    *
    * @access   private
    * @param    array
    */
    function _entryExists($primary)
    {
        $this->_prepareConnection();
        $primary = $this->_mapFields($primary);

        $tmp = array();
        foreach ($primary as $key => $value) {
            array_push($tmp, $key.'='.$this->_db->quoteSmart($value));
        }

        $query  = 'SELECT * FROM '.$this->_table.' WHERE '.implode( ' AND ', $tmp );
        $result = $this->_db->getRow( $query, array(), DB_FETCHMODE_ASSOC );

        if (empty($result)) {
            return false;
        }

        return $result;
    }

   /**
    * map the values to the correct fields
    *
    * @access   private
    * @param    array       values
    * @return   array       values mapped to the correct fields
    */
    function _mapFields( $values )
    {
        if (empty($this->_fieldMap)) {
            return $values;
        }

        $fields =   array();
        foreach ($this->_fieldMap as $el => $field) {
            if (!isset($values[$el])) {
                continue;
            }

            $fields[$field] = $values[$el];
        }
        return $fields; 
    }

   /**
    * map the fields to the correct elements
    *
    * @access   private
    * @param    array       values
    * @return   array       values mapped to the correct fields
    */
    function _unmapFields( $values )
    {
        if (empty($this->_fieldMap)) {
            return $values;
        }

        $fields = array();
        foreach ($this->_fieldMap as $el => $field) {
            if( !isset($values[$field])) {
                continue;
            }

            $fields[$el] = $values[$field];
        }
        return $fields; 
    }

   /**
    * prepare the DB connection
    *
    * @access   private
    */
    function _prepareConnection()
    {
        if ($this->_db != null) {
            return true;
        }
        
        if (is_object($this->_dsn)) {
            $this->_db = &$this->_dsn;
            return true;
        }

        $this->_db = &DB::connect($this->_dsn);
        return true;
    }
}
?>