<script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<style type="text/css">
    img {width:100px;}
</style>
<form name="upload" action="upload.php" id="upload" ENCTYPE="multipart/form-data" method="post">
    <div>
        <img id="uploadPreview1" src="no_image.jpg" /><br />
        <input id="userfile1" type="file" name="userfile" onchange="PreviewImage(1);" />
    </div>
    <div>
        <img id="uploadPreview2" src="no_image.jpg" /><br />
        <input id="userfile2" type="file" name="userfile" onchange="PreviewImage(2);" />
    </div>
    <div>
        <img id="uploadPreview3" src="no_image.jpg" /><br />
        <input id="userfile3" type="file" name="userfile" onchange="PreviewImage(3);" />
    </div>
    <div>
        <img id="uploadPreview4" src="no_image.jpg" /><br />
        <input id="userfile4" type="file" name="userfile" onchange="PreviewImage(4);" />
    </div>
    <input type="submit" name="upload" value="Przeslij">
    
</form>    
<script type="text/javascript">
    function PreviewImage(no) {
        var oFReader = new FileReader();
        oFReader.readAsDataURL(document.getElementById("userfile"+no).files[0]);

        oFReader.onload = function (oFREvent) {
            document.getElementById("uploadPreview"+no).src = oFREvent.target.result;
        };
    }
</script>

<?php

$site_name = $_SERVER['HTTP_HOST'];
$url_dir = "http://".$_SERVER['HTTP_HOST'].dirname($_SERVER['PHP_SELF']);
$url_this =  "http://".$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF'];

$upload_dir = "uploads/";
$upload_url = $url_dir."/uploads/";
$message ="";

//create uploads directory if not exist
//If it does not work, create on your own and change permission.
if (!is_dir("uploads")) {
    die ("uploads directory doesn't exist");
}

if ($_FILES['userfile']) {
    $message = do_upload($upload_dir, $upload_url);
}
else {
    $message = "Załaduj plik do przeslania ";
}

print $message;

function do_upload($upload_dir, $upload_url) {

    $temp_name = $_FILES['userfile']['tmp_name'];
    $file_name = uniqid()."-".$_FILES['userfile']['name'];
    $file_type = $_FILES['userfile']['type'];
    $file_size = $_FILES['userfile']['size'];
    $result    = $_FILES['userfile']['error'];
    $file_url  = $upload_url.$file_name;
    $file_path = $upload_dir.$file_name;

    //File Name Check
    if ( $file_name =="") {
        $message = "Nieprawidłowe nazwy pliku";
        return $message;
    }
    //File Size Check
      else if ( $file_size > 5000000000) {
        $message = "Za duze zdjecie, przekroczyło 500MB!.";
        return $message;
    }
    //File Type Check
    else if ( $file_type == "text/plain" ) {
        $message = "Sorry, You cannot upload any script file";
        return $message;
    }

    $result  =  move_uploaded_file($temp_name, $file_path);
    $message = ($result)?"Plik został przeslany:

<textarea name=\"kod\" rows=\"5\" cols=\"50\">
$file_url
</textarea></form>
<center><h3>Plik został przesłany, skopiuj wygenerowany link.</h3><center/>
<br>
<a href=$file_url>$file_url</a>" :
              "Somthing is wrong with uploading a file.";

    return $message;
}
?>