simple php script for a discord application that adds a user to an already existing bot group via oauth2, resolves a code (((made this two days ago))

grouppe.php

<?php
//ini_set('display_errors', true);

define('CLIENT_ID', '');
define('CLIENT_SECRET', '');

// token for a bot, needs to be prefixed with Bot
define('TOKEN', '');
// group channel that you have already created, lol,
define('CHANNEL_ID', '');

define('API_ENDPOINT', 'https://discord.com/api/v6');
// sobbing emoji
define('SOBBING', '&#128557;');

function reqFailed() {
	// if there's an error then it will have already been printed at this point
	?><style>
		div {
			font-size: 72px;
		}
	</style>
	<div>
		<?php
		for($i = 0; $i < 70; $i++) {
			// print sob emoji that many times
			?><?=SOBBING?><?php
		}
		?>
	</div>
	<?php
}

// represents the full url of the page
$thisURL = 'http' . (isset($_SERVER['HTTPS']) ? 's' : '') . '://' . $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF'];

if(empty($_GET['code'])) {
	header('Location: /');

	exit();
}

// so we have code now i guess

// get an oauth2 access token
$postData = array(
	'grant_type' => 'authorization_code',
	'scope' => 'gdm.join identify',
	// if the request doesn't work, this might likely be the cause
	'redirect_uri' => $thisURL,

	'client_id' => CLIENT_ID,
	'client_secret' => CLIENT_SECRET,
	'code' => $_GET['code']
);

$requestOpts = array(
	'http' => array(
		// makes it so that it doesn't exception on bad requests and whatnot
		'ignore_errors' => true,
		'method' => 'POST',
		'header' => 'Content-Type: application/x-www-form-urlencoded',
		'content' => http_build_query($postData)
	)
);

$requestContext = stream_context_create($requestOpts);

ini_set('display_errors', true);
$responseContent = file_get_contents(API_ENDPOINT . '/oauth2/token', false, $requestContext);
ini_set('display_errors', false);

if(!$responseContent) {
	reqFailed();
	exit();
}

$oauthResponse = json_decode($responseContent);

if(isset($oauthResponse->error)) {
	// oh no an error
	header('Content-Type: text/plain');
	if($oauthResponse->error === 'invalid_request') {
		http_response_code(400);
		if($oauthResponse->error_description === 'Invalid "code" in request.') {
			echo 'this url is expired. ';
		}
		echo 'bad request!!!!';
		exit();
	}
	http_response_code(500);
	echo 'error. here, you figure it out:' . PHP_EOL;
	print_r($oauthResponse);
}
// assuming that our response is valid now
if(!isset($oauthResponse->access_token)) {
	http_response_code(500);
	echo 'i didnt find an access token i dont know how to handle this im just gonna die';
	exit();
}
// ughhh time to get the user
$requestOpts = array(
	'http' => array(
		'ignore_errors' => true,
		'method' => 'GET',
		'header' => 'Authorization: ' . $oauthResponse->token_type . ' ' . $oauthResponse->access_token
	)
);
$requestContext = stream_context_create($requestOpts);

ini_set('display_errors', true);
$responseContent = file_get_contents(API_ENDPOINT . '/users/@me', false, $requestContext);
ini_set('display_errors', false);

if(!$responseContent) {
        reqFailed();
        exit();
}

$userResponse = json_decode($responseContent);
//$response->id

$postData = array(
        'access_token' => $oauthResponse->access_token,
        'nick' => 'seth',
);

$requestOpts = array(
	'http' => array(
		'ignore_errors' => true,
		'method' => 'PUT',
		'header' => 'Authorization: ' . TOKEN . "\r\n"
			. 'Content-Type: application/json',
		'content' => json_encode($postData)
	)
);
$requestContext = stream_context_create($requestOpts);

ini_set('display_errors', true);
$responseContent = file_get_contents(ENDPOINT . '/channels/' . CHANNEL_ID
		. '/recipients/' . $userResponse->id, false, $requestContext);
ini_set('display_errors', false);

if($responseContent === false) {
	reqFailed();
	exit();
}

// uhh error handling lol not

header('Content-Type: text/plain');
// accepted
http_response_code(202);
?>thank you, <?=$userResponse->username?>