<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.2.4 or newer
 *
 * NOTICE OF LICENSE
 *
 * Licensed under the Open Software License version 3.0
 *
 * This source file is subject to the Open Software License (OSL 3.0) that is
 * bundled with this package in the files license.txt / license.rst.  It is
 * also available through the world wide web at this URL:
 * http://opensource.org/licenses/OSL-3.0
 * If you did not receive a copy of the license and are unable to obtain it
 * through the world wide web, please send an email to
 * licensing@ellislab.com so we can send you a copy immediately.
 *
 * @package		CodeIgniter
 * @author		EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
 * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
 * @link		http://codeigniter.com
 * @since		Version 3.0
 * @filesource
 */

/**
 * Firebird/Interbase Database Adapter Class
 *
 * Note: _DB is an extender class that the app controller
 * creates dynamically based on whether the query builder
 * class is being used or not.
 *
 * @package		CodeIgniter
 * @subpackage	Drivers
 * @category	Database
 * @author		EllisLab Dev Team
 * @link		http://codeigniter.com/user_guide/database/
 */
class CI_DB_ibase_driver extends CI_DB {

	public $dbdriver = 'ibase';

	// The character used to escape with
	protected $_escape_char = '"';

	// clause and character used for LIKE escape sequences
	protected $_like_escape_str = " ESCAPE '%s' ";
	protected $_like_escape_chr = '!';

	protected $_random_keyword = ' Random()'; // database specific random keyword

	// Keeps track of the resource for the current transaction
	protected $trans;

	/**
	 * Non-persistent database connection
	 *
	 * @return	resource
	 */
	public function db_connect()
	{
		return @ibase_connect($this->hostname.':'.$this->database, $this->username, $this->password, $this->char_set);
	}

	// --------------------------------------------------------------------

	/**
	 * Persistent database connection
	 *
	 * @return	resource
	 */
	public function db_pconnect()
	{
		return @ibase_pconnect($this->hostname.':'.$this->database, $this->username, $this->password, $this->char_set);
	}

	// --------------------------------------------------------------------

	/**
	 * Database version number
	 *
	 * @return	string
	 */
	public function version()
	{
		if (isset($this->data_cache['version']))
		{
			return $this->data_cache['version'];
		}

		if (($service = ibase_service_attach($this->hostname, $this->username, $this->password)))
		{
			$this->data_cache['version'] = ibase_server_info($service, IBASE_SVC_SERVER_VERSION);

			// Don't keep the service open
			ibase_service_detach($service);
			return $this->data_cache['version'];
		}

		return FALSE;
	}

	// --------------------------------------------------------------------

	/**
	 * Execute the query
	 *
	 * @param	string	an SQL query
	 * @return	resource
	 */
	protected function _execute($sql)
	{
		return @ibase_query($this->conn_id, $sql);
	}

	// --------------------------------------------------------------------

	/**
	 * Begin Transaction
	 *
	 * @return	bool
	 */
	public function trans_begin($test_mode = FALSE)
	{
		// When transactions are nested we only begin/commit/rollback the outermost ones
		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
		{
			return TRUE;
		}

		// Reset the transaction failure flag.
		// If the $test_mode flag is set to TRUE transactions will be rolled back
		// even if the queries produce a successful result.
		$this->_trans_failure = ($test_mode === TRUE);

		$this->trans = @ibase_trans($this->conn_id);

		return TRUE;
	}

	// --------------------------------------------------------------------

	/**
	 * Commit Transaction
	 *
	 * @return	bool
	 */
	public function trans_commit()
	{
		// When transactions are nested we only begin/commit/rollback the outermost ones
		if ( ! $this->trans_enabled OR $this->_trans->depth > 0)
		{
			return TRUE;
		}

		return @ibase_commit($this->trans);
	}

	// --------------------------------------------------------------------

	/**
	 * Rollback Transaction
	 *
	 * @return	bool
	 */
	public function trans_rollback()
	{
		// When transactions are nested we only begin/commit/rollback the outermost ones
		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
		{
			return TRUE;
		}

		return @ibase_rollback($this->trans);
	}

	// --------------------------------------------------------------------

	/**
	 * Escape String
	 *
	 * @param	string
	 * @param	bool	whether or not the string will be used in a LIKE condition
	 * @return	string
	 */
	public function escape_str($str, $like = FALSE)
	{
		if (is_array($str))
		{
			foreach ($str as $key => $val)
			{
				$str[$key] = $this->escape_str($val, $like);
			}

			return $str;
		}

		// escape LIKE condition wildcards
		if ($like === TRUE)
		{
			return str_replace(array($this->_like_escape_chr, '%', '_'),
						array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),
						$str);
		}

		return $str;
	}

	// --------------------------------------------------------------------

	/**
	 * Affected Rows
	 *
	 * @return	int
	 */
	public function affected_rows()
	{
		return @ibase_affected_rows($this->conn_id);
	}

	// --------------------------------------------------------------------

	/**
	 * Insert ID
	 *
	 * @param	string	$generator_name
	 * @param	int	$inc_by
	 * @return	int
	 */
	public function insert_id($generator_name, $inc_by = 0)
	{
		//If a generator hasn't been used before it will return 0
		return ibase_gen_id('"'.$generator_name.'"', $inc_by);
	}

	// --------------------------------------------------------------------

	/**
	 * List table query
	 *
	 * Generates a platform-specific query string so that the table names can be fetched
	 *
	 * @param	bool
	 * @return	string
	 */
	protected function _list_tables($prefix_limit = FALSE)
	{
		$sql = 'SELECT "RDB$RELATION_NAME" FROM "RDB$RELATIONS" WHERE "RDB$RELATION_NAME" NOT LIKE \'RDB$%\' AND "RDB$RELATION_NAME" NOT LIKE \'MON$%\'';

		if ($prefix_limit !== FALSE && $this->dbprefix !== '')
		{
			return $sql.' AND "RDB$RELATION_NAME" LIKE \''.$this->escape_like_str($this->dbprefix)."%' "
				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
		}

		return $sql;
	}

	// --------------------------------------------------------------------

	/**
	 * Show column query
	 *
	 * Generates a platform-specific query string so that the column names can be fetched
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _list_columns($table = '')
	{
		return 'SELECT "RDB$FIELD_NAME" FROM "RDB$RELATION_FIELDS" WHERE "RDB$RELATION_NAME" = '.$this->escape($table);
	}

	// --------------------------------------------------------------------

	/**
	 * Field data query
	 *
	 * Generates a platform-specific query so that the column data can be retrieved
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _field_data($table)
	{
		$this->qb_limit = 1;
		$sql = $this->_limit('SELECT * FROM '.$this->protect_identifiers($table));
		$this->qb_limit = 0;
		return $sql;
	}

	// --------------------------------------------------------------------

	/**
	 * Error
	 *
	 * Returns an array containing code and message of the last
	 * database error that has occured.
	 *
	 * @return	array
	 */
	public function error()
	{
		return array('code' => ibase_errcode(), 'message' => ibase_errmsg());
	}

	// --------------------------------------------------------------------

	/**
	 * From Tables
	 *
	 * This public function implicitly groups FROM tables so there is no confusion
	 * about operator precedence in harmony with SQL standards
	 *
	 * @param	array
	 * @return	string
	 */
	protected function _from_tables($tables)
	{
		return is_array($tables) ? implode(', ', $tables) : $tables;
	}

	// --------------------------------------------------------------------

	/**
	 * Update statement
	 *
	 * Generates a platform-specific update string from the supplied data
	 *
	 * @param	string	the table name
	 * @param	array	the update data
	 * @return	string
	 */
	protected function _update($table, $values)
	{
		$this->qb_limit = FALSE;
		return parent::_update($table, $values);
	}

	// --------------------------------------------------------------------

	/**
	 * Truncate statement
	 *
	 * Generates a platform-specific truncate string from the supplied data
	 *
	 * If the database does not support the truncate() command,
	 * then this method maps to 'DELETE FROM table'
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _truncate($table)
	{
		return 'DELETE FROM '.$table;
	}

	// --------------------------------------------------------------------

	/**
	 * Delete statement
	 *
	 * Generates a platform-specific delete string from the supplied data
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _delete($table)
	{
		$this->qb_limit = FALSE;
		return parent::_delete($table);
	}

	// --------------------------------------------------------------------

	/**
	 * Limit string
	 *
	 * Generates a platform-specific LIMIT clause
	 *
	 * @param	string	the sql query string
	 * @return	string
	 */
	protected function _limit($sql)
	{
		// Limit clause depends on if Interbase or Firebird
		if (stripos($this->version(), 'firebird') !== FALSE)
		{
			$select = 'FIRST '.$this->qb_limit
				.($this->qb_offset ? ' SKIP '.$this->qb_offset : '');
		}
		else
		{
			$select = 'ROWS '
				.($this->qb_offset ? $this->qb_offset.' TO '.($this->qb_limit + $this->qb_offset) : $this->qb_limit);
		}

		return preg_replace('`SELECT`i', 'SELECT '.$select, $sql);
	}

	// --------------------------------------------------------------------

	/**
	 * Close DB Connection
	 *
	 * @return	void
	 */
	protected function _close()
	{
		@ibase_close($this->conn_id);
	}

}

/* End of file ibase_driver.php */
/* Location: ./system/database/drivers/ibase/ibase_driver.php */