Scratch

<?
    /* Post-Liker:
    An appliccation which allows you to dynamically like and unlike posts on the Scratch forums!
    */
    
    function printImage($hasAlreadyLiked, $likesCount) {
        // Print small like/unlike image
        if($hasAlreadyLiked === true) {
        $img = imagecreatefrompng('unlikeBG.png');
        } else {
        $img = imagecreatefrompng('likeBG.png');
        }
        $text_colour = imagecolorallocate($img, 1, 1, 180);
        $font = realpath('font.ttf');
        imagettftext($img, 11, 0, 10, imagefontheight(7), $text_colour, $font, $likesCount . " likes");
        $whit = imagecolorallocate($img, 0, 0, 0);
        imagepng($img);
        imagecolortransparent($img, $whit);
        header('Content-type: image/png');
        imagedestroy($img);
    }
    
    $id = $_GET['id'];    
    if(is_numeric($id) === false) {
        // Post ID is not a number
        die;
    }
    
    if($_GET['mode'] == 'img') { // Display image with like count        
        // Find likes count
        if(file_exists('likes/' . $id)) {
            $arr = explode('/', file_get_contents('likes/' . $id));
            if($arr[0] === "") {
                unset($arr[0]);
            }
            $likes = count($arr);
            // Find whether user has liked yet
            if(in_array($_SERVER['REMOTE_ADDR'], $arr)) {
                $hasliked = true;
            } else {
                $hasliked = false;
            }
        } else {
            $likes = 0;
            $hasliked = false;
        }
        printImage($hasliked, $likes);
    }
    
    elseif($_GET['mode'] == 'like') { // Add/remove like from database
        // Check whether like exists
        if(file_exists('likes/' . $id)) {
            // Check whether user has already liked
            $arr = explode('/', file_get_contents('likes/' . $id));
            if(in_array($_SERVER['REMOTE_ADDR'], $arr)) {
                $arr = array_diff($arr, array($_SERVER['REMOTE_ADDR']));
                file_put_contents('likes/' . $id, implode('/', $arr));
                if(count($arr) === 0) {
                    unlink('likes/' . $id);
                }
            } else {
                $arr[] = $_SERVER['REMOTE_ADDR'];
                file_put_contents('likes/' . $id, implode('/', $arr));
            }
        } else {
            file_put_contents('likes/' . $id, $_SERVER['REMOTE_ADDR']);
        }
        // Redirect to post
        header('Location: http://scratch.mit.edu/forums/viewtopic.php?pid=' . $id . '#p' . $id);
    }

javascript:(prompt("Copy this:", "[url=http://modshare2.tk/likes/?id="+(window.location+"").replace("http://scratch.mit.edu/forums/viewtopic.php?id=", "")+"&mode=like][img]http://modshare2.tk/likes/?id="+(window.location+"").replace("http://scratch.mit.edu/forums/viewtopic.php?id=", "")+"&mode=img[/img][/url]"))