Mini Shell

<?php
/**
 * Database
 *
 * @author Andrew Esteves <andrew@digitalnativa.com.br>
 * @copyright Digital Nativa (www.digitalnativa.com.br)
 */

class DB
{
	/**
	 * @var connection instance
	 */
	private static $_instance;

	/**
	 * Creates a PDO instance representing a connection to a database
	 * Singleton
	 */
	public static function connection()
	{
		if(!isset(self::$_instance)) {
			try {
				self::$_instance = new PDO('mysql:host=' . DB_HOST . ';dbname=' . DB_NAME, DB_USER, DB_PASS);
				self::$_instance->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
				self::$_instance->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ);
			} catch (PDOException $e) {
				echo $e->getMessage();
			}
		}

		return self::$_instance;
	}

	/**
	 * Prepares a statement for execution and returns a statement object
	 *
	 * @param String $sql
	 * @return Object
	 */
	public static function prepare($sql)
	{
		return self::connection()->prepare($sql);
	}

	/**
	 * Returns the ID of the last inserted row or sequence value
	 * 
	 * @return Int
	 */
	public static function lastInsertId(){
    	return self::connection()->lastInsertId();
    }
}