<?php

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP

 *

 * This content is released under the MIT License (MIT)

 *

 * Copyright (c) 2014 - 2017, British Columbia Institute of Technology

 *

 * 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 - 2017, British Columbia Institute of Technology (http://bcit.ca/)

 * @license	http://opensource.org/licenses/MIT	MIT License

 * @link	https://codeigniter.com

 * @since	Version 1.0.0

 * @filesource

 */

defined('BASEPATH') OR exit('No direct script access allowed');



/**

 * Database Utility Class

 *

 * @category	Database

 * @author		EllisLab Dev Team

 * @link		https://codeigniter.com/user_guide/database/

 */
#[\AllowDynamicProperties]
abstract class CI_DB_utility {



	/**

	 * Database object

	 *

	 * @var	object

	 */

	protected $db;



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



	/**

	 * List databases statement

	 *

	 * @var	string

	 */

	protected $_list_databases		= FALSE;



	/**

	 * OPTIMIZE TABLE statement

	 *

	 * @var	string

	 */

	protected $_optimize_table	= FALSE;



	/**

	 * REPAIR TABLE statement

	 *

	 * @var	string

	 */

	protected $_repair_table	= FALSE;



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



	/**

	 * Class constructor

	 *

	 * @param	object	&$db	Database object

	 * @return	void

	 */

	public function __construct(&$db)

	{

		$this->db =& $db;

		log_message('info', 'Database Utility Class Initialized');

	}



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



	/**

	 * List databases

	 *

	 * @return	array

	 */

	public function list_databases()

	{

		// Is there a cached result?

		if (isset($this->db->data_cache['db_names']))

		{

			return $this->db->data_cache['db_names'];

		}

		elseif ($this->_list_databases === FALSE)

		{

			return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;

		}



		$this->db->data_cache['db_names'] = array();



		$query = $this->db->query($this->_list_databases);

		if ($query === FALSE)

		{

			return $this->db->data_cache['db_names'];

		}



		for ($i = 0, $query = $query->result_array(), $c = count($query); $i < $c; $i++)

		{

			$this->db->data_cache['db_names'][] = current($query[$i]);

		}



		return $this->db->data_cache['db_names'];

	}



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



	/**

	 * Determine if a particular database exists

	 *

	 * @param	string	$database_name

	 * @return	bool

	 */

	public function database_exists($database_name)

	{

		return in_array($database_name, $this->list_databases());

	}



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



	/**

	 * Optimize Table

	 *

	 * @param	string	$table_name

	 * @return	mixed

	 */

	public function optimize_table($table_name)

	{

		if ($this->_optimize_table === FALSE)

		{

			return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;

		}



		$query = $this->db->query(sprintf($this->_optimize_table, $this->db->escape_identifiers($table_name)));

		if ($query !== FALSE)

		{

			$query = $query->result_array();

			return current($query);

		}



		return FALSE;

	}



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



	/**

	 * Optimize Database

	 *

	 * @return	mixed

	 */

	public function optimize_database()

	{

		if ($this->_optimize_table === FALSE)

		{

			return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;

		}



		$result = array();

		foreach ($this->db->list_tables() as $table_name)

		{

			$res = $this->db->query(sprintf($this->_optimize_table, $this->db->escape_identifiers($table_name)));

			if (is_bool($res))

			{

				return $res;

			}



			// Build the result array...

			$res = $res->result_array();

			$res = current($res);

			$key = str_replace($this->db->database.'.', '', current($res));

			$keys = array_keys($res);

			unset($res[$keys[0]]);



			$result[$key] = $res;

		}



		return $result;

	}



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



	/**

	 * Repair Table

	 *

	 * @param	string	$table_name

	 * @return	mixed

	 */

	public function repair_table($table_name)

	{

		if ($this->_repair_table === FALSE)

		{

			return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;

		}



		$query = $this->db->query(sprintf($this->_repair_table, $this->db->escape_identifiers($table_name)));

		if (is_bool($query))

		{

			return $query;

		}



		$query = $query->result_array();

		return current($query);

	}



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



	/**

	 * Generate CSV from a query result object

	 *

	 * @param	object	$query		Query result object

	 * @param	string	$delim		Delimiter (default: ,)

	 * @param	string	$newline	Newline character (default: \n)

	 * @param	string	$enclosure	Enclosure (default: ")

	 * @return	string

	 */

	public function csv_from_result($query, $delim = ',', $newline = "\n", $enclosure = '"')

	{

		if ( ! is_object($query) OR ! method_exists($query, 'list_fields'))

		{

			show_error('You must submit a valid result object');

		}



		$out = '';

		// First generate the headings from the table column names

		foreach ($query->list_fields() as $name)

		{

			$out .= $enclosure.str_replace($enclosure, $enclosure.$enclosure, $name).$enclosure.$delim;

		}



		$out = substr($out, 0, -strlen($delim)).$newline;



		// Next blast through the result array and build out the rows

		while ($row = $query->unbuffered_row('array'))

		{

			$line = array();

			foreach ($row as $item)

			{

				$line[] = $enclosure.str_replace($enclosure, $enclosure.$enclosure, $item).$enclosure;

			}

			$out .= implode($delim, $line).$newline;

		}



		return $out;

	}



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



	/**

	 * Generate XML data from a query result object

	 *

	 * @param	object	$query	Query result object

	 * @param	array	$params	Any preferences

	 * @return	string

	 */

	public function xml_from_result($query, $params = array())

	{

		if ( ! is_object($query) OR ! method_exists($query, 'list_fields'))

		{

			show_error('You must submit a valid result object');

		}



		// Set our default values

		foreach (array('root' => 'root', 'element' => 'element', 'newline' => "\n", 'tab' => "\t") as $key => $val)

		{

			if ( ! isset($params[$key]))

			{

				$params[$key] = $val;

			}

		}



		// Create variables for convenience

		extract($params);



		// Load the xml helper

		get_instance()->load->helper('xml');



		// Generate the result

		$xml = '<'.$root.'>'.$newline;

		while ($row = $query->unbuffered_row())

		{

			$xml .= $tab.'<'.$element.'>'.$newline;

			foreach ($row as $key => $val)

			{

				$xml .= $tab.$tab.'<'.$key.'>'.xml_convert($val).'</'.$key.'>'.$newline;

			}

			$xml .= $tab.'</'.$element.'>'.$newline;

		}



		return $xml.'</'.$root.'>'.$newline;

	}



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



	/**

	 * Database Backup

	 *

	 * @param	array	$params

	 * @return	string

	 */

	public function backup($params = array())

	{

		// If the parameters have not been submitted as an

		// array then we know that it is simply the table

		// name, which is a valid short cut.

		if (is_string($params))

		{

			$params = array('tables' => $params);

		}



		// Set up our default preferences

		$prefs = array(

			'tables'		=> array(),

			'ignore'		=> array(),

			'filename'		=> '',

			'format'		=> 'gzip', // gzip, zip, txt

			'add_drop'		=> TRUE,

			'add_insert'		=> TRUE,

			'newline'		=> "\n",

			'foreign_key_checks'	=> TRUE

		);



		// Did the user submit any preferences? If so set them....

		if (count($params) > 0)

		{

			foreach ($prefs as $key => $val)

			{

				if (isset($params[$key]))

				{

					$prefs[$key] = $params[$key];

				}

			}

		}



		// Are we backing up a complete database or individual tables?

		// If no table names were submitted we'll fetch the entire table list

		if (count($prefs['tables']) === 0)

		{

			$prefs['tables'] = $this->db->list_tables();

		}



		// Validate the format

		if ( ! in_array($prefs['format'], array('gzip', 'zip', 'txt'), TRUE))

		{

			$prefs['format'] = 'txt';

		}



		// Is the encoder supported? If not, we'll either issue an

		// error or use plain text depending on the debug settings

		if (($prefs['format'] === 'gzip' && ! function_exists('gzencode'))

			OR ($prefs['format'] === 'zip' && ! function_exists('gzcompress')))

		{

			if ($this->db->db_debug)

			{

				return $this->db->display_error('db_unsupported_compression');

			}



			$prefs['format'] = 'txt';

		}



		// Was a Zip file requested?

		if ($prefs['format'] === 'zip')

		{

			// Set the filename if not provided (only needed with Zip files)

			if ($prefs['filename'] === '')

			{

				$prefs['filename'] = (count($prefs['tables']) === 1 ? $prefs['tables'] : $this->db->database)

							.date('Y-m-d_H-i', time()).'.sql';

			}

			else

			{

				// If they included the .zip file extension we'll remove it

				if (preg_match('|.+?\.zip$|', $prefs['filename']))

				{

					$prefs['filename'] = str_replace('.zip', '', $prefs['filename']);

				}



				// Tack on the ".sql" file extension if needed

				if ( ! preg_match('|.+?\.sql$|', $prefs['filename']))

				{

					$prefs['filename'] .= '.sql';

				}

			}



			// Load the Zip class and output it

			$CI =& get_instance();

			$CI->load->library('zip');

			$CI->zip->add_data($prefs['filename'], $this->_backup($prefs));

			return $CI->zip->get_zip();

		}

		elseif ($prefs['format'] === 'txt') // Was a text file requested?

		{

			return $this->_backup($prefs);

		}

		elseif ($prefs['format'] === 'gzip') // Was a Gzip file requested?

		{

			return gzencode($this->_backup($prefs));

		}



		return;

	}



}

