<?php
// Form code for mail submissions
// For usage with hugo site

// Anti exploit code, not perfect but should throw a wrench into a bot's plan 
// This code has been used on several sites before and does seem to do a decent job, not perfect but pretty good

session_start();

class antibot {

    private $passfail;

    function __constructor(){
        $passfail = 0;
    }

    private function fromtest() {
        if ($_SERVER['HTTP_REFERER'] = "http://yourwebsite.com/contactus/"){
        $passfail = 1;
        }
        
    }

    private function ratetest() {
        if (!$_SESSION['last_submit']){
            $_SESSION['last_submit'] = time(); // May not stick to a bot but doing it anyhow
            $passfail = 2;
        }else{
           //print "Session found"; 
        if (time()-$_SESSION['last_submit'] < 60){
            // Purposefully not letting them know what the interval is
        die('Error: Message not sent, rate limit hit. Please wait a few minutes and try again.');
        $passfail = 0;
        }else{
        $_SESSION['last_submit'] = time();
            $passfail = 2;
        }
    }
    
    }

    private function traptest() {
        if($_POST['website']){
            $passfail = 0;
        }else{
            $passfail = 3;
        }
        return $passfail;
    }

    private function test_input($data) { // Cleans the input 
        $data = trim($data);
        $data = stripslashes($data);
        $data = htmlspecialchars($data);
        return $data;
      }

    private function sndmsg($target) {
        // First clean the data
        $fname = $this->test_input($_POST["fname"]);
        $lname = $this->test_input($_POST["lname"]);
        $email = $this->test_input($_POST["email"]);
        $comments = $this->test_input($_POST["comments"]);
        // compile cleaned message
        $msg = "From $fname Subject $lname email $email with message $comments";
        mail($target,"Website Form Submission",$msg);
    }

    public function do_tests(){
        $this->fromtest();
        $this->ratetest();
        $result = $this->traptest();
        if($result == 3) {
            $this->sndmsg("you@yoursite.com");
            return 3;
        }else{
            return 0;
        }
        
    }
    
}

$lcheck = new antibot();

$winner = $lcheck->do_tests();

if ($winner == 3){
    echo "Form Submitted thank you!";
}else{
    echo "Error: Send failed, please try again.";
}

?>