<?php
/* SVN FILE: $Id$ */

/**
 * SQLite layer for DBO
 *
 * Long description for file
 *
 * PHP versions 4 and 5
 *
 * CakePHP :  Rapid Development Framework <http://www.cakephp.org/>
 * Copyright (c) 2006, Cake Software Foundation, Inc.
 *                     1785 E. Sahara Avenue, Suite 490-204
 *                     Las Vegas, Nevada 89104
 *
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 *
 * @filesource
 * @copyright    Copyright (c) 2006, Cake Software Foundation, Inc.
 * @link         http://www.cakefoundation.org/projects/info/cakephp CakePHP Project
 * @package      cake
 * @subpackage   cake.cake.libs.model.dbo
 * @since        CakePHP v 0.9.0
 * @version      $Revision$
 * @modifiedby   $LastChangedBy$
 * @lastmodified $Date$
 * @license      http://www.opensource.org/licenses/mit-license.php The MIT License
 */

/**
 * Include DBO.
 */
uses('model'.DS.'datasources'.DS.'dbo_source');

/**
 * DBO implementation for the SQLite DBMS.
 *
 * Long description for class
 *
 * @package    cake
 * @subpackage cake.cake.libs.model.dbo
 * @since      CakePHP v 0.9.0
 */
class DBO_SQLite extends DboSource
{

/**
 * Connects to the database using config['file'] as a filename.
 *
 * @param array $config Configuration array for connecting
 * @return mixed
 */
    function connect($config)
    {
      if ($config)
      {
         $this->config = $config;
         $this->_conn = $config['connect']($config['file']);
      }
      $this->connected = $this->_conn? true: false;

      if($this->connected)
      {
         return $this->_conn;
      }
      else
      {
//die('Could not connect to DB.');
      }
    }

/**
 * Disconnects from database.
 *
 * @return boolean True if the database could be disconnected, else false
 */
    function disconnect()
    {
      return sqlite_close($this->_conn);
    }

/**
 * Executes given SQL statement.
 *
 * @param string $sql SQL statement
 * @return resource Result resource identifier
 */
    function execute($sql)
    {
      return sqlite_query($this->_conn, $sql);
    }

/**
 * Returns a row from given resultset as an array.
 *
 * @return array The fetched row as an array
 */
    function fetchRow()
    {
      return sqlite_fetch_array($this->_result);
    }

/**
 * Returns an array of tables in the database. If there are no tables, an error is raised and the application exits.
 *
 * @return array Array of tablenames in the database
 */
    function tablesList()
    {
      $result = sqlite_query($this->_conn, "SELECT name FROM sqlite_master WHERE type='table' ORDER BY name;");

      if (!$result)
      {
         trigger_error(ERROR_NO_TABLE_LIST, E_USER_NOTICE);
         exit;
      }
      else
      {
         $tables = array();
         while ($line = sqlite_fetch_array($result))
         {
            $tables[] = $line[0];
         }
         return $tables;
      }
    }

/**
 * Returns an array of the fields in given table name.
 *
 * @param string $tableName     Name of database table to inspect
 * @return array                 Fields in table. Keys are name and type
 */
    function fields($tableName)
    {
      $fields = false;
      $cols = sqlite_fetch_column_types($tableName, $this->_conn);

      foreach ($cols as $column => $type)
      {
         $fields[] = array('name'=>$column, 'type'=>$type);
      }

      return $fields;
    }

/**
 * Returns a quoted and escaped string of $data for use in an SQL statement.
 *
 * @param string $data String to be prepared for use in an SQL statement
 * @return string Quoted and escaped
 */
    function prepareValue($data)
    {
      return "'" . sqlite_escape_string($data) . "'";
    }

/**
 * Returns a formatted error message from previous database operation.
 *
 * @return string Error message
 */
    function lastError()
    {
      return sqlite_last_error($this->_conn)? sqlite_last_error($this->_conn).': '.sqlite_error_string(sqlite_last_error($this->_conn)): null;
    }

/**
 * Returns number of affected rows in previous database operation. If no previous operation exists, this returns false.
 *
 * @return int Number of affected rows
 */
    function lastAffected()
    {
      return $this->_result? sqlite_changes($this->_conn): false;
    }

/**
 * Returns number of rows in previous resultset. If no previous resultset exists,
 * this returns false.
 *
 * @return int Number of rows in resultset
 */
    function lastNumRows()
    {
      return $this->_result? sqlite_num_rows($this->_result): false;
    }

/**
 * Returns the ID generated from the previous INSERT operation.
 *
 * @return int
 */
    function lastInsertId()
    {
      return sqlite_last_insert_rowid($this->_conn);
    }

/**
 * Returns a limit statement in the correct format for the particular database.
 *
 * @param int $limit         Limit of results returned
 * @param int $offset         Offset from which to start results
 * @return string             SQL limit/offset statement
 */
    function selectLimit($limit, $offset=null)
    {
      return " LIMIT {$limit}".($offset? ", {$offset}": null);
    }
}
?>