<?php
namespace Core;
use \PDO;

class Database
{
    private $instance = null;

    private $username;
    private $password;
    private $server;
    private $dbname;

    public function __construct($username, $password, $server, $dbname)
    {
        $this->username = $username;
        $this->password = $password;
        $this->server = $server;
        $this->dbname = $dbname;
    }

    public function getInstance()
    {
        if ($this->instance == null) {
            $this->createInstance();
        }

        return $this->instance;
    }

    private function createInstance() {
        $this->instance = new PDO("mysql:host={$this->server};dbname={$this->dbname};charset=utf8", $this->username, $this->password);
        $this->instance->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    }
}