<?php
/**
 * Codon PHP Framework
 *	www.nsslive.net/codon
 * Software License Agreement (BSD License)
 *
 * Copyright (c) 2008 Nabeel Shahzad, nsslive.net
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Nabeel Shahzad
 * @copyright Copyright (c) 2008, Nabeel Shahzad
 * @link http://www.nsslive.net
 * @license BSD License
 * 
 * @author Originally by Justin Vincent (justin@visunet.ie)
 * @link http://php.justinvincent.com
 */
/**********************************************************************
*  ezDB Database specific class - mySQL
*/
 
class ezDB_mysql extends ezDB_Base
{
 
	/**
	 * Constructor, connects to database immediately, unless $dbname is blank
	 *
	 * @param string $dbuser Database username
	 * @param string $dbpassword Database password
	 * @param string $dbname Database name (if blank, will not connect)
	 * @param string $dbhost Hostname, optional, default is 'localhost'
	 * @return bool Connect status
	 *
	 */
	public function __construct($dbuser='', $dbpassword='', $dbname='', $dbhost='localhost')
	{
		if($dbname == '') return false;
 
		parent::__construct();
 
		if($this->connect($dbuser, $dbpassword, $dbhost))
		{
			return $this->select($dbname);
		}
 
		return false;
	}
 
	/**
	 * Explicitly close the connection on destruct
	 */
 
	public function __destruct()
	{
		$this->close();
	}
 
	/**
	 * Connects to database immediately, unless $dbname is blank
	 *
	 * @param string $dbuser Database username
	 * @param string $dbpassword Database password
	 * @param string $dbname Database name (if blank, will not connect)
	 * @param string $dbhost Hostname, optional, default is 'localhost'
	 * @return bool Connect status
	 *
	 */
	public function quick_connect($dbuser='', $dbpassword='', $dbname='', $dbhost='localhost')
	{
		$this->__construct($dbuser, $dbpassword, $dbname, $dbhost);
	}
 
 
	/**
	 * Connect to MySQL, but not to a database
	 *
	 * @param string $dbuser Username
	 * @param string $dbpassword Password
	 * @param string $dbhost Host, optional, default is localhost
	 * @return bool Success
	 *
	 */
	public function connect($dbuser='', $dbpassword='', $dbhost='localhost')
	{
		$this->dbh = mysql_connect($dbhost, $dbuser, $dbpassword, true);
 
		if(!$this->dbh)
		{
			if($this->use_exceptions)
				throw new ezDB_Error(mysql_error(), mysql_errno());
 
			$this->register_error(mysql_error(), mysql_errno());
			return false;
		}
 
		$this->clear_errors();
		return true;
	}
 
	/**
	 * Select a MySQL Database
	 *
	 * @param string $dbname Database name
	 * @return bool Success or not
	 *
	 */
	public function select($dbname='')
	{
		// Must have a database name
		if ($dbname == '')
		{
			if($this->use_exceptions)
				throw new ezDB_Error('No database specified!', -1);
 
			$this->register_error('No database name specified!');
			return false;
		}
		// Must have an active database connection
		if (!$this->dbh)
		{
			if($this->use_exceptions)
				throw new ezDB_Error('Invalid or inactive connection!');
 
			$this->register_error('Can\'t select database, invalid or inactive connection', -1);
			return false;
		}
 
		if(!mysql_select_db($dbname, $this->dbh))
		{
			if($this->use_exceptions)
				throw new ezDB_Error(mysql_error(), mysql_errno());
 
			$this->register_error(mysql_error($this->dbh), mysql_errno($this->dbh));
			return false;
		}
 
		$this->clear_errors();
		return true;
	}
 
	/**
	 * Close the database connection
	 */
	public function close()
	{
		return @mysql_close($this->dbh);
	}
 
	/**
	 * Format a mySQL string correctly for safe mySQL insert
	 *  (no matter if magic quotes are on or not)
	 *
	 * @param string $str String to escape
	 * @return string Returns the escaped string
	 *
	 */
	public function escape($str)
	{
		return mysql_real_escape_string(stripslashes($str), $this->dbh);
	}
 
 
	/**
	 * Returns the DB specific timestamp function (Oracle: SYSDATE, MySQL: NOW())
	 *
	 * @return string Timestamp function
	 *
	 */
	public function sysdate()
	{
		return 'NOW()';
	}
 
	/**
	 * Run the SQL query, and get the result. Returns false on failure
	 *  Check $this->error() and $this->errno() functions for any errors
	 *  MySQL returns errno() == 0 for no error. That's the most reliable check
	 *
	 * @param string $query SQL Query
	 * @return mixed Return values
	 *
	 */
	public function query($query)
	{
		// Flush cached values..
		$this->flush();
 
		// For reg expressions
		$query = trim($query);
		$this->last_query = $query;
 
		// Count how many queries there have been
		$this->num_queries++;
 
		// Use core file cache function
		if($cache = $this->get_cache($query))
		{
			return $cache;
		}
 
		// Make sure connection is ALIVEE!
		if (!$this->dbh )
		{
			if($this->use_exceptions)
				throw new ezDB_Error(mysql_error(), mysql_errno());
 
			$this->register_error('There is no active database connection!');
			return false;
		}
 
		// Perform the query via std mysql_query function..
		$this->result = mysql_query($query, $this->dbh);
 
		// If there is an error then take note of it..
		if(!$this->result && mysql_errno($this->dbh) != 0)
		{
			// Something went wrong		
			if($this->use_exceptions)		
				throw new ezDB_Error(mysql_error(), mysql_errno(), $query);
 
			$this->register_error(mysql_error(), $errno);
			return false;
		}
		else
		{
			$this->clear_errors();
		}
 
		// Query was an insert, delete, update, replace
		$is_insert = false;
		if(preg_match("/^(insert|delete|update|replace)\s+/i",$query))
		{
			$this->rows_affected = mysql_affected_rows($this->dbh);
			$this->num_rows = $this->rows_affected;
 
			$insert_id = mysql_insert_id($this->dbh);
			if($insert_id > 0)
			{
				$this->insert_id = $insert_id;
				$is_insert = true;
			}
 
			// Return number fo rows affected
			$return_val = $this->rows_affected;
		}
		// Query was a select
		else
		{
			// Take note of column info
			$i=0;
 
			if($this->result)
			{
				while ($i < mysql_num_fields($this->result))
				{
					$this->col_info[$i] = mysql_fetch_field($this->result);
					$i++;
				}
 
				// Store Query Results
				$num_rows=0;
 
				while($row = mysql_fetch_object($this->result))
				{
					// Store relults as an objects within main array
					$this->last_result[$num_rows] = $row;
					$num_rows++;
				}
 
				mysql_free_result($this->result);
			}
 
			// Log number of rows the query returned
			$this->rows_affected = $num_rows;
			$this->num_rows = $num_rows;
 
			// Return number of rows selected
			$return_val = $this->num_rows;
		}
 
		// disk caching of queries
		$this->store_cache($query,$is_insert);
 
		// If debug ALL queries
		$this->trace || $this->debug_all ? $this->debug() : null ;
 
		return $return_val;
	}
}