<?php
/**
* CodeIgniter
*
* An open source application development framework for PHP
*
* This content is released under the MIT License (MIT)
*
* Copyright (c) 2019 - 2022, CodeIgniter Foundation
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* @package CodeIgniter
* @author EllisLab Dev Team
* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
* @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
* @copyright Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
* @license https://opensource.org/licenses/MIT MIT License
* @link https://codeigniter.com
* @since Version 2.0.3
* @filesource
*/
defined('BASEPATH') OR exit('No direct script access allowed');

/**
* SQLSRV Forge Class
*
* @category Database
* @author EllisLab Dev Team
* @link https://codeigniter.com/userguide3/database/
*/
class CI_DB_sqlsrv_forge extends CI_DB_forge {

/**
* CREATE TABLE IF statement
*
* @var string
*/
protected $_create_table_if = "IF NOT EXISTS (SELECT * FROM sysobjects WHERE ID = object_id(N'%s') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)\nCREATE TABLE";

/**
* DROP TABLE IF statement
*
* @var string
*/
protected $_drop_table_if = "IF EXISTS (SELECT * FROM sysobjects WHERE ID = object_id(N'%s') AND OBJECTPROPERTY(id, N'IsUserTable') = 1)\nDROP TABLE";

/**
* UNSIGNED support
*
* @var array
*/
protected $_unsigned = array(
'TINYINT' => 'SMALLINT',
'SMALLINT' => 'INT',
'INT' => 'BIGINT',
'REAL' => 'FLOAT'
);

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

/**
* ALTER TABLE
*
* @param string $alter_type ALTER type
* @param string $table Table name
* @param mixed $field Column definition
* @return string|string[]
*/
protected function _alter_table($alter_type, $table, $field)
{
if (in_array($alter_type, array('ADD', 'DROP'), TRUE))
{
return parent::_alter_table($alter_type, $table, $field);
}

$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' ALTER COLUMN ';
$sqls = array();
for ($i = 0, $c = count($field); $i < $c; $i++)
{
$sqls[] = $sql.$this->_process_column($field[$i]);
}

return $sqls;
}

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

/**
* Field attribute TYPE
*
* Performs a data type mapping between different databases.
*
* @param array &$attributes
* @return void
*/
protected function _attr_type(&$attributes)
{
if (isset($attributes['CONSTRAINT']) && strpos($attributes['TYPE'], 'INT') !== FALSE)
{
unset($attributes['CONSTRAINT']);
}

switch (strtoupper($attributes['TYPE']))
{
case 'MEDIUMINT':
$attributes['TYPE'] = 'INTEGER';
$attributes['UNSIGNED'] = FALSE;
return;
case 'INTEGER':
$attributes['TYPE'] = 'INT';
return;
default: return;
}
}

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

/**
* Field attribute AUTO_INCREMENT
*
* @param array &$attributes
* @param array &$field
* @return void
*/
protected function _attr_auto_increment(&$attributes, &$field)
{
if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE && stripos($field['type'], 'int') !== FALSE)
{
$field['auto_increment'] = ' IDENTITY(1,1)';
}
}

}