<?php
function helper($success = NULL, $message = NULL, $results = NULL) {
    return [
        'success' => $success,
        'message' => $message,
        'results' => $results
    ];
}
function check_proxy($ip,$port,$timeout=10) {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, 'http://avanda.net/proxycek/index.php?ip='.$ip.'&port='.$port.'&timeout='.$timeout);
    curl_setopt($ch,CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch,CURLOPT_TIMEOUT,5);
    $result = json_decode(curl_exec($ch));
    curl_close($ch);
    return $result;
}
if (!empty($_POST['ip'])){
    header("Content-type: application/json");
    if(preg_match('/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}:\d{1,4}\z/is',$_POST['ip']))
    {
        $data = explode(':', $_POST['ip']);
        $ip = $data[0];
        $port = $data[1];
        $check = check_proxy($ip,$port);
        if($check->result->success){
            $result['success'] = TRUE;
            $result['message'] = 'VALID IP';
        }
        else
        {
            $result['success'] = FALSE;
            $result['message'] = 'INVALID IP';
        }

        $result['proxy'] = $check->result->proxy;
    }
    else
    {
        $result = [
            'success' => FALSE,
            'message' => 'invalid ip format',
            'proxy' => []
        ];
    }
    echo json_encode(helper($result['success'],$result['message'],$result['proxy']));
    exit();
}
?>
<center>
    <form action="" method="POST">
        <input type="text" name="ip" placeholder="e.g: 127.0.0.1:80">
        <button>Enter</button>
    </form>
</center>