Login php sul mio sito web

API
29 
<?php

$client_id = '';
$client_secret = '';
$redirect_uri = '';

if (isset($_GET['code']) && $_GET['code']) {
    $token_url = "https://id.twitch.tv/oauth2/token";
    $data = array(
        'client_id' => $client_id,
        'client_secret' => $client_secret,
        'grant_type' => 'authorization_code',
        'redirect_uri' => $redirect_uri,
        'code' => $_GET['code']
    );

    $curl = curl_init($token_url);
    curl_setopt($curl, CURLOPT_POST, true);
    curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_TIMEOUT, 1000);

    $result = curl_exec($curl);
    $i      = curl_getinfo($curl);
    curl_close($curl);

    if ($i['http_code'] == 200) {
        $result = json_decode($result, true);

        $curl = curl_init('https://api.twitch.tv/helix/user');
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_HTTPHEADER, array(
            'Client-ID: ' . $client_id,
            'Authorization: Bearer ' . $result['access_token']
        ));
        curl_setopt($curl, CURLOPT_TIMEOUT, 1000);

        $user = curl_exec($curl);
        $i    = curl_getinfo($curl);
        curl_close($curl);

        if ($i['http_code'] == 200) {
            $user = json_decode($user);

            echo '<p>Thanks ' . $user->display_name . ' <3</p>';
        } else {
            echo '<p>An error occured, please <a href="/index.php">click here and try again</a></p>';
        }
    } else {
        echo '<p>An error occured, please <a href="/index.php">click here and try again</a></p>';
    }
} else {
    $auth_url = 'https://api.twitch.tv/kraken/oauth2/authorize?response_type=code';
    $auth_url .= '&client_id=' . $client_id;
    $auth_url .= '&redirect_uri=' . $redirect_uri;
    $auth_url .= '&scope=channel:read:subscriptions';
    $auth_url .= '&force_verify=true';

    echo '<a href="' . $auth_url . '">Please Click this Link to Authenticate with Twitch</a>';
} elseif{
    $auth_url . = false{
        header("Location: index.php");
        echo = "you are not a subscriber";
    }
}

would this last part work?