<?php if (!defined('TL_ROOT')) die('You can not access this file directly!');

/**
 * TYPOlight Open Source CMS
 * Copyright (C) 2005-2010 Leo Feyer
 *
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation, either
 * version 3 of the License, or (at your option) any later version.
 * 
 * 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program. If not, please visit the Free
 * Software Foundation website at <http://www.gnu.org/licenses/>.
 *
 * PHP version 5
 * @copyright  Leo Feyer 2005-2010
 * @author     Leo Feyer <http://www.typolight.org>
 * @package    System
 * @license    LGPL
 * @filesource
 */


/**
 * Class DB_Mssql
 *
 * Driver class for MSSQL databases.
 * @copyright  Leo Feyer 2005-2010
 * @author     Leo Feyer <http://www.typolight.org>
 * @package    Driver
 */
class DB_Mssql extends Database
{

	/**
	 * List tables query
	 * @var string
	 */
	protected $strListTables = "SELECT * FROM sysobjects WHERE type='U' ORDER BY name";

	/**
	 * List fields query
	 * @var string
	 */
	protected $strListFields = "SELECT c.name, t.name, c.length, c.isnullable, m.text, sign(c.status & 0x80), sign(ISNULL(r.status, 0) & 16), sign(ISNULL(k.keyno, 0)) FROM syscolumns c JOIN systypes t ON (t.xusertype=c.xusertype) JOIN sysobjects o on (o.id=c.id) LEFT OUTER JOIN sysconstraints r ON ((r.id=o.id) AND (r.colid=c.colid)) LEFT OUTER JOIN syscomments m ON (m.id = c.cdefault) LEFT OUTER JOIN sysobjects p ON ((p.parent_obj=o.id) AND (p.xtype='PK')) LEFT OUTER JOIN sysindexes i ON ((i.id=p.parent_obj) AND (i.name=p.name)) LEFT OUTER JOIN sysindexkeys k ON ((k.id=i.id) AND (k.indid=i.indid) AND (k.colid=c.colid)) WHERE o.name='%s'";


	/**
	 * Connect to database server and select database
	 */
	protected function connect()
	{
		$strHost = $GLOBALS['TL_CONFIG']['dbHost'];

		if ($GLOBALS['TL_CONFIG']['dbPort'])
		{
			$strHost .= ',' . $GLOBALS['TL_CONFIG']['dbPort'];
		}

		if ($GLOBALS['TL_CONFIG']['dbPconnect'])
		{
			$this->resConnection = @mssql_pconnect($strHost, $GLOBALS['TL_CONFIG']['dbUser'], $GLOBALS['TL_CONFIG']['dbPass'], $GLOBALS['TL_CONFIG']['dbCharset']);
		}

		else
		{
			$this->resConnection = @mssql_connect($strHost, $GLOBALS['TL_CONFIG']['dbUser'], $GLOBALS['TL_CONFIG']['dbPass'], $GLOBALS['TL_CONFIG']['dbCharset']);
		}

		if (is_resource($this->resConnection))
		{
			@mssql_select_db($GLOBALS['TL_CONFIG']['dbDatabase'], $this->resConnection);
		}
	}


	/**
	 * Disconnect from database
	 */
	protected function disconnect()
	{
		@mssql_close($this->resConnection);
	}


	/**
	 * Return the last error message
	 * @return string
	 */
	protected function get_error()
	{
		return mssql_get_last_message();
	}


	/**
	 * Return a standardized array with field information
	 * 
	 * Standardized format:
	 * - name:       field name (e.g. my_field)
	 * - type:       field type (e.g. "int" or "number")
	 * - length:     field length (e.g. 20)
	 * - precision:  precision of a float number (e.g. 5)
	 * - null:       NULL or NOT NULL
	 * - default:    default value (e.g. "default_value")
	 * - attributes: attributes (e.g. "unsigned")
	 * - extra:      extra information (e.g. auto_increment)
	 * @param string
	 * @return string
	 * @todo This function is not tested yet, nor is the list tables and list fields statement!
	 */
	protected function list_fields($strTable)
	{
		$arrReturn = array();
		$arrFields = $this->execute(sprintf($this->strListFields, $strTable))->fetchAllAssoc();

		foreach ($arrFields as $k=>$v)
		{
			$arrReturn[$k]['name'] = $v['name'];
			$arrReturn[$k]['length'] = $v['length'];
		}

		return $arrReturn;
	}


	/**
	 * Change the current database
	 * @param  string
	 * @return boolean
	 */
	protected function set_database($strDatabase)
	{
		return @mssql_select_db($strDatabase, $this->resConnection);
	}


	/**
	 * Begin a transaction
	 */
	protected function begin_transaction()
	{
		@mssql_query("BEGIN TRAN", $this->resConnection);
	}


	/**
	 * Commit a transaction
	 */
	protected function commit_transaction()
	{
		@mssql_query("COMMIT TRAN", $this->resConnection);
	}


	/**
	 * Rollback a transaction
	 */
	protected function rollback_transaction()
	{
		@mssql_query("ROLLBACK TRAN", $this->resConnection);
	}
}


/**
 * Class DB_Mssql_Statement
 *
 * Driver class for MSSQL databases.
 * @copyright  Leo Feyer 2005-2010
 * @author     Leo Feyer <http://www.typolight.org>
 * @package    Driver
 */
class DB_Mssql_Statement extends Database_Statement
{

	/**
	 * Prepare a query and return it
	 * @param string
	 */
	protected function prepare_query($strQuery)
	{
		return $strQuery;
	}


	/**
	 * Escape a string
	 * @param  string
	 * @return string
	 */
	protected function string_escape($strString)
	{
		return "'" . str_replace("'", "''", $strString) . "'";
	}


	/**
	 * Limit the current query
	 * @param int
	 * @param int
	 */
	protected function limit_query($intRows, $intOffset)
	{
		$this->strQuery .= preg_replace('/(^\s*SELECT\s+(DISTINCT|DISTINCTROW)?)/i', '\\1 TOP ' . intval($intRows + $intOffset), $this->strQuery);
	}


	/**
	 * Execute the current query
	 * @return resource
	 */
	protected function execute_query()
	{
		return @mssql_query($this->strQuery, $this->resConnection);
	}


	/**
	 * Return the last error message
	 * @return string
	 */
	protected function get_error()
	{
		return mssql_get_last_message();
	}


	/**
	 * Return the number of affected rows
	 * @return int
	 */
	protected function affected_rows()
	{
		return @mssql_rows_affected($this->resConnection);
	}


	/**
	 * Return the last insert ID
	 * @return int
	 */
	protected function insert_id()
	{
		return @mssql_query('SELECT @@IDENTITY', $this->resConnection);
	}


	/**
	 * Explain the current query
	 * @return array
	 */
	protected function explain_query()
	{
		return false;
	}
}


/**
 * Class DB_Mssql_Result
 *
 * Driver class for MSSQL databases.
 * @copyright  Leo Feyer 2005-2010
 * @author     Leo Feyer <http://www.typolight.org>
 * @package    Driver
 */
class DB_Mssql_Result extends Database_Result
{

	/**
	 * Fetch the current row as enumerated array
	 * @return array
	 */
	protected function fetch_row()
	{
		return @mssql_fetch_row($this->resResult);
	}


	/**
	 * Fetch the current row as associative array
	 * @return array
	 */
	protected function fetch_assoc()
	{
		return @mssql_fetch_assoc($this->resResult);
	}


	/**
	 * Return the number of rows of the current result
	 * @return int
	 */
	protected function num_rows()
	{
		return @mssql_num_rows($this->resResult);
	}


	/**
	 * Return the number of fields of the current result
	 * @return int
	 */
	protected function num_fields()
	{
		return @mssql_num_fields($this->resResult);
	}


	/**
	 * Get column information
	 * @param  int
	 * @return object
	 */
	protected function fetch_field($intOffset)
	{
		return @mssql_fetch_field($this->resResult, $intOffset);
	}


	/**
	 * Free the current result
	 */
	public function free()
	{
		if (is_resource($this->resResult))
		{
			@mssql_free_result($this->resResult);
		}
	}
}

?>