<?php
//complete code for index.php
error_reporting(E_ALL);
ini_set("display_errors", 1);
include_once "classes/Page_Data.class.php";
$pageData = new Page_Data();
$pageData->addScript("js/lightbox.js");
$pageData->title = "Dynamic image gallery";
$pageData->addCSS("css/layout.css");
$pageData->addCSS("css/navigation.css");
$pageData->content = include_once "views/navigation.php";
$userClicked = isset($_GET["page"]);
if ($userClicked) {
    $fileToLoad = $_GET["page"];
} else {
    $fileToLoad = "gallery";
}
$pageData->content .= include_once "views/$fileToLoad.php";
$page = include_once "templates/page.php";
echo $page;