file upload with multiple files not working properly - php

Question

I have this weird problem with my code:
There are three input file tags. These are upload scenarios and their results:
All three files simultaneously - success
Only picture - Success
Only audio - Failure
Only video - Failure
One picture and one audio - picture succeeds, audio fails
One picture and one video - picture succeeds, video fails
One audio and one video - one of them succeeds
<?php
session_start();
if(!isset($_SESSION["username"])){
header('Location: index.php');
}
if(isset($_POST["year"])){
ini_set('display_errors',1);
error_reporting(E_ALL);
var_dump($_FILES);
$year = $_POST["year"];
$height = $_POST["height"];
$weight = $_POST["weight"];
$school = $_POST["school"];
$class = $_POST["class"];
$target_dir_img = "./pictures/";
$target_dir_aud = "./audios/";
$target_dir_vid = "./videos/";
$uploadOk = 1;
$target_files = array();
$target_img = basename($_FILES['uploadedFiles']['name'][0]);
var_dump($target_img);
if(strcmp($target_img,'')){
$imageFileType = pathinfo($target_img,PATHINFO_EXTENSION);
$newImageName = $target_dir_img . $_SESSION['username']."_".$_POST['year'].".". $imageFileType;
if($imageFileType != "jpg" && $imageFileType != "jpeg") {
echo "Sorry, only JPG, JPEG, PNG & GIF files are allowed.";
$uploadOk = 0;
}
else {
$target_files[] = $newImageName;
}
}
// Allow certain file formats
$target_aud = basename($_FILES['uploadedFiles']['name'][1]);
var_dump($target_aud);
if(strcmp($target_aud,'')) {
$audioFileType = pathinfo($target_aud, PATHINFO_EXTENSION);
$newAudioName = $target_dir_aud . $_SESSION['username']."_".$_POST['year'].".". $audioFileType;
if($audioFileType != "mp3") {
echo "Sorry, only MP3 files are allowed.";
$uploadOk = 0;
}
else {
$target_files[] = $newAudioName;
}
}
$target_vid = basename($_FILES['uploadedFiles']['name'][2]);
var_dump($target_vid);
if(strcmp($target_vid,'')){
$videoFileType = pathinfo($target_vid, PATHINFO_EXTENSION);
$newVideoName = $target_dir_vid . $_SESSION['username']."_".$_POST['year'].".". $videoFileType;
if($videoFileType != "mp4") {
echo "Sorry, only MP4 files are allowed.";
$uploadOk = 0;
}
else {
$target_files[] = $newVideoName;
}
}
var_dump($target_files);
// Check if $uploadOk is set to 0 by an error
if ($uploadOk == 0) {
echo "Sorry, your file was not uploaded.";
// if everything is ok, try to upload file
} else {
for($i=0; $i<sizeof($target_files); $i++){
if (move_uploaded_file($_FILES['uploadedFiles']['tmp_name'][$i], $target_files[$i])) {
echo "The file ". basename( $_FILES['uploadedFiles']['name'][$i]). " has been uploaded.";
} else {
echo "Sorry, there was an error uploading your file.";
}
}
}
}
?>
<h1>Welcome <?php echo $_SESSION["username"]; ?>!</h1>
<h2>Data</h2>
<form action="" method="POST" enctype="multipart/form-data">
<p><label>Select Year : </label>
<select id="year" name="year">
<?php
for($i=1901; $i<=2020; $i++){
echo '<option value="'.$i.'">'.$i.'</option>';
}
?>
</select></p>
<p><label>Height : </label>
<input type="text" id="height" name="height" placeholder="Height" /></p>
<p><label>Weight : </label>
<input type="text" id="weight" name="weight" placeholder="Weight" /></p>
<p><label>School : </label>
<input type="text" id="school" name="school" placeholder="School" /></p>
<p><label>Class : </label>
<input type="text" id="class" name="class" placeholder="Class" /></p>
<p><label>Choose picture : </label>
<input type="file" id="picture" name="uploadedFiles[]" accept="image/jpeg, image/jpg" /></p>
<p><label>Choose Audio : </label>
<input type="file" id="audio" name="uploadedFiles[]" accept="audio/mp3" /></p>
<p><label>Choose Video : </label>
<input type="file" id="video" name="uploadedFiles[]" accept="video/mp4" /></p>
<input type="submit" id="submit" name="submit" value="submit" /></p>
</form>
Any inputs on how it may be happening?