<?php

/**
* @version      database.php 2011-02-14 08:01
* @package      ErCox.Framework
* @copyright    Copyright (C) ErCox, Damjan Krstevski. All rights reserved.
* @license      GNU/GPL, see LICENSE.php
*/


    /**
    * Database class
    *
    * @package      ErCox.Framework
    */
    class Database {

        /**
        * MySql Connection
        *
        * @access public
        * @var resource
        */
        public $connection = NULL;


        /**
        * MySql Hostname
        *
        * @access private
        * @var string
        */
        private $DbHost     = NULL;


        /**
        * MySql Root Username
        *
        * @access private
        * @var string
        */
        private $DbUser     = NULL;


        /**
        * MySql Root Password
        *
        * @access private
        * @var string
        */
        private $DbPass     = NULL;


        /**
        * Used Database
        *
        * @access private
        * @var string
        */
        private $DbData     = NULL;


        /**
        * Database TimeOut
        *
        * @access private
        * @var int
        */
        private $DbTimeout  = 10;


        /**
        * Database Table Prefix
        *
        * @access private
        * @var string
        */
        private $DbPrefix   = NULL;


        /**
        * MySql Error Number
        *
        * @access private
        * @var int
        */
        private $DbError    = 0;



        /**
        * Database object constructor
        *
        * @access public
        * @param    array $params Database Information (Host, User, Pass, Data, Prefix, [TimeOut])
        */
        public function __construct( $params = NULL )
        {
            /* Validate Params */
            if ( !$this->set_dbparams($params) )
            {
                return;
            }

            /* Validate if the MySQL functions is defined */
            if( !$this->test_db_functions(true) )
            {
                return;
            }

            /* Connect with the MySql database */
            if( !$this->connect() )
            {
                return;
            }

            if( !$this->select_db() )
            {
                return;
            }

            if( !$this->set_charset() )
            {
                return;
            }
        }


        /**
        * Database object destructor
        *
        * @access   public
        */
        public function __destruct()
        {
            /* Close the connection */
            $this->close();

            /* Free Memory */
            $this->DbHost       = NULL;
            $this->DbUser       = NULL;
            $this->DbPass       = NULL;
            $this->DbData       = NULL;
            $this->DbPrefix     = NULL;
        }


        /**
        * Method to check if the MySql functions are defined
        *
        * @access   public
        * @param    boolean $all True to check all MySql functions that are used
        * @return   boolean True if the MySql functions are defined
        */
        public function test_db_functions( $all = false )
        {
            if( !function_exists("mysql_connect") )
            {
                return false;
            }

            if( !function_exists("mysql_select_db") )
            {
                return false;
            }

            if( !function_exists("mysql_query") )
            {
                return false;
            }

            if( !function_exists("mysql_close") )
            {
                return false;
            }

            /* Validate non essential functions */
            if( $all === true )
            {
                if( !function_exists("mysql_free_result") )
                {
                    return false;
                }

                if( !function_exists("mysql_real_escape_string") )
                {
                    return false;
                }

                if( !function_exists("mysql_set_charset") )
                {
                    return false;
                }
            }

            return true;
        }


        /**
        * Set database information
        *
        * @access   public
        * @param    array $params Database Information (Host, User, Pass, Data, Prefix, [TimeOut])
        * @return   boolean True if successful
        */
        public function set_dbparams( $params )
        {
            /* Validate params */
            if( empty($params) ) { $this->set_dberror(1); return false; } /* Invalid params */

            /* Set the values */
            $this->DbHost       = isset($params["host"])    ? $params["host"]       : "";
            $this->DbUser       = isset($params["user"])    ? $params["user"]       : "";
            $this->DbPass       = isset($params["pass"])    ? $params["pass"]       : "";
            $this->DbData       = isset($params["data"])    ? $params["data"]       : "";
            $this->DbPrefix     = isset($params["prefix"])  ? $params["prefix"]     : "";
            $this->DbTimeout    = isset($params["timeout"]) ? $params["timeout"]    : $this->DbTimeout;

            return true;
        }


        /**
        * Set database error
        *
        * @access   private
        * @param    int Error number
        */
        private function set_dberror( $no )
        {
            $this->DbError = $no;
        }


        /**
        * Get database error
        *
        * @access   public
        * @return   int Error Number
        */
        public  function get_dberror()
        {
            return $this->DbError;
        }


        /**
        * Set database timeout
        *
        * The configuration option will keep this new value during the script's execution
        *
        * @access   private
        * @param    int $to Database timeout
        */
        private function set_dbtimeout( $to )
        {
            $this->DbTimeout = $to;
        }


        /**
        * Get database timeout value
        *
        * @access   public
        * @return   int Database timeout value
        */
        public function get_dbtimeout()
        {
            return $this->DbTimeout;
        }


        /**
        * Set database hostname
        *
        * @access   private
        * @param    string $val Database hostname
        */
        private function set_dbhost( $val )
        {
            $this->DbHost = empty($val) ? $val : "";
        }


        /**
        * Get database hostname
        *
        * @access   public
        * @return   string Database hostname
        */
        public  function get_dbhost()
        {
            return $this->DbHost;
        }


        /**
        * Set database username
        *
        * @access   private
        * @param    string $val Database root password
        */
        private function set_dbuser( $val )
        {
            $this->DbUser = empty($val) ? $val : "";
        }


        /**
        * Get database username
        *
        * @access   public
        * @return   string Database root username
        */
        public  function get_dbuser()
        {
            return $this->DbUser;
        }


        /**
        * Set database timeout value
        *
        * @access   private
        * @param    string $val Database root password
        */
        private function set_dbpass( $val )
        {
            $this->DbPass = empty($val) ? $val : "";
        }
        //public function get_dbpass() {} This function is not valid for safety reasons


        /**
        * Set the name of the used
        *
        * @access   private
        * @param    string $val The name of the database
        */
        private function set_dbdata( $val )
        {
            $this->DbData = empty($val) ? $val : "";
        }


        /**
        * Get the name of the database
        *
        * @access   public
        * @return   string The name of the used database
        */
        public  function get_dbdata()
        {
            return $this->DbData;
        }


        /**
        * Set table prefix
        *
        * @access   private
        * @param    string $val The table prefix
        */
        private function set_dbprefix( $val )
        {
            $this->DbPrefix = empty($val) ? $$val : "";
        }


        /**
        * Get table prefix
        *
        * @access   public
        * @return   string The table prefix
        */
        public  function get_dbprefix()
        {
            return $this->DbPrefix;
        }


        /**
        * Method to connect to a MySql database
        *
        * @access   public
        * @return   boolean True if successful
        */
        public function connect()
        {
            /* If already connected, return */
            if( $this->is_connected($this->connection) )
            {
                return true;
            }

            /* Validate param if is int */
            if( !is_int($this->DbTimeout) )
            {
                $this->DbTimeout = 10;
            }

            /* Set the timeout */
            @ini_set("mysql.connect_timeout", $this->DbTimeout);

            /* Connect with the MySql database */
            $this->connection = @mysql_connect($this->DbHost, $this->DbUser, $this->DbPass);
            return $this->is_connected($this->connection) ? true : false;
        }


        /**
        * Method to determine if the object is connected to an MySql server
        *
        * @access   public
        * @param    string $link The database connection
        * @param    boolean $flag If flag is true will try to connect to the database [Default: false]
        * @return   boolean True if connected
        */
        public function is_connected( $link, $flag = false )
        {
            /* Only determine if the object is connected */
            if( $flag === false )
            {
                return @is_resource($this->connection) ? true : false;
            }
            else
            {
                /* If object is connected return */
                if( @is_resource($this->connection) )
                {
                    return true;
                }
                else
                {
                    /* Try to connect and if not sucessfully return */
                    if( $this->connect() === false )
                    {
                        return false;
                    }
                }
            }

            return true;
        }


        /**
        * Method for selecting the database to be used
        *
        * @access   public
        * @return   boolean True if successful
        */
        public function select_db()
        {
            /* Determine connection, if not connected try to connect */
            if( !$this->is_connected($this->connection, true) )
            {
                return false;
            }

            return @mysql_select_db($this->DbData) ? true : false;
        }


        /**
        * Method to execute SQL command
        *
        * @access   public
        * @param    string $sql The SQL command
        * @return   boolean True if successful
        */
        public function query( $sql )
        {
            /* Validate SQL value */
            if( empty($sql) )
            {
                return false;
            }

            /* Determine connection, if not connected try to connect */
            if( !$this->is_connected($this->connection, true) )
            {
                return false;
            }

            return @mysql_query($sql, $this->connection) ? true : false;
        }


        /**
        * Method to check whether or not the connection to the server is working.
        *
        * @access   public
        * @return   boolean True if successful
        */
        public function ping_db()
        {
            return @mysql_ping($this->connection) ? true : false;
        }


        /**
        * Method to free all memory associated with the result identifier
        *
        * @access   public
        * @param    resource $result The result resource that is being evaluated
        * @return   boolean True if successful
        */
        public function free_memory( $result )
        {
            /* Allow only resource */
            if( !is_resource($result) )
            {
                return false;
            }

            return @mysql_free_result($this->connection) ? true : false;
        }


        /**
        * Method to close the database connection
        *
        * @access   public
        * @return   boolean True if successful
        */
        public function close()
        {
            /* If already connected, try to close database connection */
            if( $this->is_connected($this->connection) )
            {
                return @mysql_close($this->connection) ? true : false;
            }

            return true;
        }


        /**
        * Method to escapes special characters in a string for use in an SQL statement
        *
        * @access   public
        * @param    string $str The string that is to be escaped
        * @return   string True if successful
        */
        public function escape( $str )
        {
            if( empty($str) )
            {
                $str = "";
                return true;
            }

            return @mysql_real_escape_string($str);
        }


        /**
        * Method to sets the client character set
        *
        * @access   public
        * @param    string $charset A valid character set name [Default UTF8]
        * @return   boolean True if successful
        */
        public function set_charset( $charset = "UTF8" )
        {
            if( empty($charset) )
            {
                $charset = "UTF8";
            }

            return @mysql_set_charset($charset) ? true : false;
        }

        /* mysql_fetch_field */
        /* mysql_result */
    }

?>