<?php

include('db.php'); // This should initialize a PDO connection, and contain helper functions for queries

function router() {
    switch($_GET['a']) {
        case ('view'):
            do_view();
        break;
        case ('edit'):
            do_edit();
        break;
        case ('save'):
            $result = do_save();
            if ($result === true) {
                header('location: /?a=view&id='.$GET['id']);
            } else {
                header('location: /?a=view&id='.$GET['id'].'&error='.urlencode($result));
            }
        break;
    }
}

function do_view() {
    // Get data here, put it in variables
    include('view.phtml');
}

function do_edit() {
    if (empty($_GET['id'])) {
        die("ID is required");
    }
    $id = $_GET['id'];
    // Get data here, put it in variables
    include('edit.phtml');
}

function do_save() {
    if (empty($_GET['id'])) {
        die("ID is required");
    }
    if (false) {
        return "Example validation error";
    }
    $id = $_GET['id'];
    // Get the inputs from $_POST, construct a query to save it into pdo
    return true;
}