<?php
//define a maxim size for the uploaded images in Kb
define ("MAX_SIZE","1000");
include_once "connect_to_mysql.php";
$userid = $_SESSION['id'];
$truckid = $_GET['truck'];

//This function reads the extension of the file. It is used to determine if the file is an image by checking the extension.
function getExtension($str) {
$i = strrpos($str,".");
if (!$i) { return ""; }
$l = strlen($str) - $i;
$ext = substr($str,$i+1,$l);
return $ext;
}

//This variable is used as a flag. The value is initialized with 0 (meaning no error found)
//and it will be changed to 1 if an errro occures.
//If the error occures the file will not be uploaded.
$errors=0;
//checks if the form has been submitted
if(isset($_POST['Submit']))
{
//reads the name of the file the user submitted for uploading
$image=$_FILES['image']['name'];
//if it is not empty
if ($image)
{
//get the original name of the file from the clients machine
$filename = stripslashes($_FILES['image']['name']);
//get the extension of the file in a lower case format
$extension = getExtension($filename);
$extension = strtolower($extension);
//if it is not a known extension, we will suppose it is an error and will not upload the file,
//otherwise we will do more tests
if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") && ($extension != "gif"))
{
//print error message
echo '<h1>Unknown extension!</h1>';
$errors=1;
}
else
{
//get the size of the image in bytes
//$_FILES['image']['tmp_name'] is the temporary filename of the file
//in which the uploaded file was stored on the server
$size=filesize($_FILES['image']['tmp_name']);

//compare the size with the maxim size we defined and print error if bigger
if ($size > MAX_SIZE*10024)
{
echo '<h1>You have exceeded the size limit!</h1>';
$errors=1;
}

//we will give an unique name, for example the time in unix time format
$image_name = time().'.'.$extension;

//the new name will be containing the full path where will be stored (images folder)
$newname = "memberFiles/$userid/".$image_name;
//we verify if the image has been uploaded, and print error instead
$copied = copy($_FILES['image']['tmp_name'], $newname);
$pics = mysql_query("INSERT INTO pics (userid, truckid, location) VALUES ('$userid', '$truckid', '$image_name')") or die (mysql_error());

if (!$copied)
{
echo '<h1>Copy unsuccessfull!</h1>';
$errors=1;
}}}}

//If no errors registred, print the success message
if(isset($_POST['Submit']) && !$errors)
{
echo "<h4>File Uploaded Successfully!</h4> ";
}

?>