<?php

    define( "DB_HOSTNAME"   , 0x20 );
    define( "DB_USERNAME"   , 0x40 );
    define( "DB_PASSWORD"   , 0x60 );

    class database
    {
        /*  Configuration of the Database.
        *///¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
        const   DEFAULT_PERSISTANT = true;          // Will we connect with a persistant connection to the database by default?
        const   DEFAULT_ACCOUNT    = 0;             // Upon creation of the databases this account will be loaded automatically if it exists.
        const   DEFAULT_CONNECT    = true;          // Will we automatically connect to the database once this class is initiated?


        /*  The Database System.
        *///¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
        private $pData             = array();       // The data of all MySQL accounts.
        private $pAccount          = null;          // The current account of the MySQL user.

        public  $mSQLs             = array();
        public  $mResults          = array();




        public function isConnected()
        {
            return $this->pAccount['connected']  === true ? true : false;
        }
        public function isPersistant()
        {
            return $this->pAccount['persistant'] === true ? true : false;
        }
        public function changeAccount( $id, $persistant = true )
        {
            if( $this->disconnect() )
            {
                $this->pAccount = $this->pData[$id];
            }
            else
            {
                throw new Exception( 'MySQL: Could not change account from "' . $this->pAccount[DB_USERNAME] . '" to "' . $this->pData[$id][DB_USERNAME] . '".' );
            }

            return $this->connect( $persistant );
        }

        public function connect( $persistant = PERSISTANT )
        {
            if( !$this->isConnected() )
            {
                if( $persistant )
                {
                    $this->pAccount['persistant'] = true;
                    $this->pAccount['handle']     = @mysql_pconnect( $this->pAccount[DB_HOSTNAME], $this->pAccount[DB_USERNAME], $this->pAccount[DB_PASSWORD] );
                }
                else
                {
                    $this->pAccount['persistant'] = false;
                    $this->pAccount['handle']     = @mysql_connect( $this->pAccount[DB_HOSTNAME], $this->pAccount[DB_USERNAME], $this->pAccount[DB_PASSWORD] );
                }

                if( $this->pAccount['handle'] )
                {
                    $this->pAccount['connected'] = true;

                    return true;
                }
                else
                {
                    throw new Exception( 'MySQL: Could not connect to "' . $this->pAccount[DB_HOSTNAME] . '" with "' . $this->pAccount[DB_USERNAME] . '".' );
                }
            }

            return false;
        }
        public function pConnect()
        {
            return $this->connect( true );
        }
        public function disconnect()
        {
            if( $this->isConnected() )
            {
                if ( mysql_close( $this->pAccount['handle'] ) )
                {
                    $this->pAccount['connected'] = false;

                    return true;
                }
            }

            return false;
        }
        public function select( $id = 0 )
        {
            if( $this->isConnected() )
            {
                $list = mysql_list_dbs( $this->pAccount['handle'] );

                while( $row = mysql_fetch_object( $list ) )
                {
                    $this->pAccount['databases'][$row->Database] = $row->Database;
                }

                if( is_int( $id ) )
                {
                    $this->pAccount['databases'] = array_values( $this->pAccount['databases'] );
                }


                if( array_key_exists( $id, $this->pAccount['databases'] ) )
                {
                    if( $this->pAccount['link'] = mysql_select_db( $this->pAccount['databases'][$id], $this->pAccount['handle'] ) )
                    {
                        $this->pAccount['selected'] = true;

                        return true;
                    }
                    else
                    {
                        throw new Exception( 'MySQL: Could not select database "' . $id . '" on "' . $this->pAccount[DB_HOSTNAME] . '".' );
                    }
                }
                elseif( sizeOf( $this->pAccount['databases'] ) == 0 )
                {
                    throw new Exception( 'MySQL: There are no databases to be selected on "' . $this->pAccount[DB_HOSTNAME] . '".' );
                }
                else
                {
                    throw new Exception( 'MySQL: Unkown database select error on "' . $this->pAccount[DB_HOSTNAME] . '".' );
                }
            }
            else
            {
                try
                {
                    $this->connect();
                    try
                    {
                        $this->select( $id );
                    }
                    catch( Exception $e )
                    {
                        die( $e->getMessage() );
                    }
                }
                catch( Exception $e )
                {
                    die( $e->getMessage() );
                }
            }

            return false;
        }
        public function query( $sql )
        {
            if( $this->isConnected() )
            {
                if( !$result = @mysql_query( $sql ) )
                {
                    throw new Exception( 'MySQL: Querry could not be executed: "' . mysql_error() . '".' );
                }
                else
                {
                    $this->mSQLs[]    = $sql;
                    $this->mResults[] = $result;

                    return $result;
                }
            }

            return false;
        }
        public function freeLastResult()
        {
            mysql_free_result( end( $this->mResults ) );
        }
        public function freeAllResults()
        {
            foreach( $this->mResults as $result )
            {
                mysql_free_result( $result );
            }
        }


        public function __construct( $data, $account = DEFAULT_ACCOUNT, $connect = DEFAULT_CONNECT, $pconnect = DEFAULT_PERSISTANT, $database = null )
        {
            if( isset( $data ) )
            {
                if( is_array( $data ) )
                {
                    if( sizeOf( $data ) > 0 )
                    {
                        foreach( $data as $account => $details )
                        {
                            if( sizeOf( $details ) === 3 )
                            {
                                $data[$account][DB_HOSTNAME] = isset( $data[$account][DB_HOSTNAME] ) ? $data[$account][DB_HOSTNAME] : '';
                                $data[$account][DB_USERNAME] = isset( $data[$account][DB_USERNAME] ) ? $data[$account][DB_USERNAME] : '';
                                $data[$account][DB_PASSWORD] = isset( $data[$account][DB_PASSWORD] ) ? $data[$account][DB_PASSWORD] : '';
                            }
                            else
                            {
                                die( 'The database configuration "' . key( $account ) . '" is missing some key values.' );
                            }
                        }
                    }
                    else
                    {
                        die( 'The database configuration does not contain any accounts.' );
                    }
                }
                else
                {
                    die( 'The database configuration is not configured right.' );
                }
            }
            else
            {
                die( 'The database configuration is not configured right.' );
            }

            $this->pData    = $data;
            $this->pAccount = $this->pData[$account];

            if( $connect )
            {
                if( $pconnect )
                {
                    $this->connect( true );
                }
                else
                {
                    $this->connect( false );
                }
                if( isset( $database ) )
                {
                    $this->select( $database );
                }
            }
        }
    }

?>


<?php

    // This part should be in a configuration system of the website.

    define( "DB_READ"   , 0 );
    define( "DB_WRITE"  , 1 );
    define( "DB_FULL"   , 2 );

    $dbinfo = array
    (
        DB_READ => array
        (
            DB_HOSTNAME => 'localhost',
            DB_USERNAME => 'read',
            DB_PASSWORD => 'TheAxeEffect1987',
        ),

        DB_WRITE => array
        (
            DB_HOSTNAME => 'localhost',
            DB_USERNAME => 'write',
            DB_PASSWORD => 'TheAxeEffect1987',
        ),

        DB_FULL => array
        (
            DB_HOSTNAME => 'localhost',
            DB_USERNAME => 'full',
            DB_PASSWORD => 'TheAxeEffect1987',
        )
    );

//  $db = new database( $dbinfo[, DEFAULT_ACCOUNT [, AUTO_CONNECT [, USE_PCONNECT [, AUTO_SELECT_DATABASE )
    $db = new database( $dbinfo, DB_READ, true, true, 'test' );

    if( $db->changeAccount( DB_FULL ) )
    {
        $db->query( "SELECT * FROM test" );
        $db->freeAllResults();
    }
    else
    {
        echo 'false';
    }

?>