<?php

class MySQL {
    private $hostname;
    private $username;
    private $password;
    private $database;
    private $link;
    private $result;
    private $config = false;

    public function __construct() {

    }

    public function close() {
        mysql_close($this->link);
    }

    public function connect($hostname = null, $username = null, $password = null) {
        if (func_num_args() == 0) {
            if ($this->config) {
                $hostname = $this->hostname;
                $username = $this->username;
                $password = $this->password;
            } else {
                die("MySQL::connect() failed -- the config is missing.");
            }
        }

        $this->link = mysql_connect($hostname, $username, $password);

        if (!$this->link) {
            die("MySQL::connect() failed -- the connection couldn't be established: ".mysql_error());
        }
    }

    public function fetchRow() {
        return mysql_fetch_row($this->result);
    }

    public function loadConfig($config = "config.php") {
        require_once $config;

        if (!defined("HOSTNAME") || !defined("USERNAME") || !defined("PASSWORD") || !defined("DATABASE")) {
            die("MySQL::loadConfig() failed -- the required configuration constants couldn't be found.");
        }

        $this->hostname = HOSTNAME;
        $this->username = USERNAME;
        $this->password = PASSWORD;
        $this->database = DATABASE;
        $this->config = true;
    }

    public function query($query) {
        $this->result = mysql_query($query);

        if (!$this->result) {
            die("MySQL::query -- invalid query: " . mysql_error());
        }
    }

    public function selectDatabase($database = null) {
        if (func_num_args() == 0) {
            if ($this->config) {
                $database = $this->database;
            } else {
                die("MySQL::selectDatabase() failed -- the config is missing.");
            }
        }

        $selected = mysql_select_db($database, $this->link);

        if (!$selected) {
            die ("MySQL::selectDatabase() failed -- the database couldn't be selected: ".mysql_error());
        }
    }
}

?>