PHP Decode

<?php 
use PHPMailer\PHPMailer\PHPMailer; 
use PHPMailer\PHPMailer\Exception; 
 
require 'lib/src/Exception.php'; 
require 'lib/src/PHPMailer.php'; 
require 'lib/src/SMTP.php'; 
 
set_time_limit(10800); //max execution time - 3 hours 
 
function generateRandomString($characters, $length = 10) { 
    $charactersLength = strlen($characters); 
    $randomString = ''; 
    for ($i = 0; $i < $length; $i++) { 
        $randomString .= $characters[rand(0, $charactersLength - 1)]; 
    } 
    return $randomString; 
} 
 
if ($_SERVER['REQUEST_METHOD'] === 'POST') { 
    $post = (object) $_POST; 
     
    //separate recipients 
    $recipients = explode("
", str_replace("
", "", $post->letter_recipients)); 
     
    foreach ($recipients as $recipient) { 
        $recipient = trim($recipient); 
     
        //create mailing obj 
        $mail = new PHPMailer(true); 
         
        try { 
            //Encoding 
            if ($post->encode == 'encodeIso') { 
                $mail->CharSet = 'iso-8859-1'; 
            } elseif ($post->encode == 'encodeUtd8') { 
                $mail->CharSet = 'UTF-8'; 
            } 
             
            $mail->Encoding = 'base64'; //TODO:TEST 
     
            //Attachments 
            if (isset($_FILES['files']) && isset($_FILES['files']['name']) && !empty($_FILES['files']['name'][0])) { 
                foreach ($_FILES['files']['name'] as $i => $name) { 
                    $mail->AddAttachment($_FILES['files']['tmp_name'][$i], $_FILES['files']['name'][$i]); 
                } 
            } 
     
            //Templates 
            $string = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; 
            $letters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; 
            $number = '0123456789'; 
            $post->letter_message = str_replace("#RECIPIENT#", $recipient, $post->letter_message); 
            $post->letter_message = str_replace("#FROM#", $post->from_email, $post->letter_message); 
            $post->letter_message = str_replace("#DATE#", date('d/m/Y'), $post->letter_message); 
            $post->letter_message = str_replace("#TIME#", date('g:i A'), $post->letter_message); 
            $post->letter_message = str_replace("#RANDOMLETTERS#", generateRandomString($letters, 8), $post->letter_message); 
            $post->letter_message = str_replace("#RANDOMNUMBER#", generateRandomString($number, 8), $post->letter_message); 
            $post->letter_message = str_replace("#RANDOMSTRING#", generateRandomString($string, 8), $post->letter_message); 
            $post->letter_message = str_replace("#RANDOMMD5#", md5(generateRandomString($string)), $post->letter_message); 
             
            $post->letter_subject = str_replace("#RECIPIENT#", $recipient, $post->letter_subject); 
            $post->letter_subject = str_replace("#FROM#", $post->from_email, $post->letter_subject); 
            $post->letter_subject = str_replace("#DATE#", date('d/m/Y'), $post->letter_subject); 
            $post->letter_subject = str_replace("#TIME#", date('g:i A'), $post->letter_subject); 
            $post->letter_subject = str_replace("#RANDOMLETTERS#", generateRandomString($letters, 8), $post->letter_subject); 
            $post->letter_subject = str_replace("#RANDOMNUMBER#", generateRandomString($number, 8), $post->letter_subject); 
            $post->letter_subject = str_replace("#RANDOMSTRING#", generateRandomString($string, 8), $post->letter_subject); 
            $post->letter_subject = str_replace("#RANDOMMD5#", md5(generateRandomString($string)), $post->letter_subject); 
             
            $post->from_name = str_replace("#RECIPIENT#", $recipient, $post->from_name); 
            $post->from_name = str_replace("#FROM#", $post->from_email, $post->from_name); 
            $post->from_name = str_replace("#DATE#", date('d/m/Y'), $post->from_name); 
            $post->from_name = str_replace("#TIME#", date('g:i A'), $post->from_name); 
            $post->from_name = str_replace("#RANDOMLETTERS#", generateRandomString($letters, 8), $post->from_name); 
            $post->from_name = str_replace("#RANDOMNUMBER#", generateRandomString($number, 8), $post->from_name); 
            $post->from_name = str_replace("#RANDOMSTRING#", generateRandomString($string, 8), $post->from_name); 
            $post->from_name = str_replace("#RANDOMMD5#", md5(generateRandomString($string)), $post->from_name); 
             
            $post->from_email = str_replace("#RECIPIENT#", $recipient, $post->from_email); 
            $post->from_email = str_replace("#FROM#", $post->from_email, $post->from_email); 
            $post->from_email = str_replace("#DATE#", date('d/m/Y'), $post->from_email); 
            $post->from_email = str_replace("#TIME#", date('g:i A'), $post->from_email); 
            $post->from_email = str_replace("#RANDOMLETTERS#", generateRandomString($letters, 8), $post->from_email); 
            $post->from_email = str_replace("#RANDOMNUMBER#", generateRandomString($number, 8), $post->from_email); 
            $post->from_email = str_replace("#RANDOMSTRING#", generateRandomString($string, 8), $post->from_email); 
            $post->from_email = str_replace("#RANDOMMD5#", md5(generateRandomString($string)), $post->from_email); 
             
            //set subject 
            $mail->Subject = $post->letter_subject; 
     
            //set message 
            $mail->Body = $post->letter_message; 
            if ($post->type == 'typeHtml') { 
                $mail->isHTML(true); 
            } 
     
            $mail->AltBody = $post->letter_message; 
            //message type 
            if ($post->type == 'typeHtml') { 
                $mail->isHTML(true); 
            } 
     
            //add recipient 
            $mail->addAddress($recipient); 
     
            //add reply-to 
            if (!empty($post->letter_reply)) { 
                $mail->addReplyTo($post->letter_reply); 
            } 
     
            //use smtp 
            //smtp auth 
            //smtp host 
            //smtp port 
            //smtp name 
            //smtp pwd 
            //smtp secure 
             
            if ($post->smtp_on) { 
                $mail->SMTPDebug = 2; 
                $mail->isSMTP(); 
                $mail->Host = $post->smtp_host; 
                $mail->Port = $post->smtp_port ? $post->smtp_port : 587; 
         
                $mail->SMTPAuth = true; 
                $mail->Username = $post->smtp_username; 
                $mail->Password = $post->smtp_password; 
         
                if ($post->smtp_secure == 'tls') { 
                    $mail->SMTPSecure = 'tls'; 
                } elseif ($post->smtp_secure == 'ssl') { 
                    $mail->SMTPSecure = 'ssl'; 
                } 
            } 
     
            //set from, name 
            $mail->setFrom($post->from_email, $post->from_name); 
     
            $mail->send(); 
            $mail->clearAllRecipients(); 
            print_r($recipient . ' - Successful!<br/>'); 
        } catch (Exception $e) { 
            echo 'Message could not be sent. Error: ', $mail->ErrorInfo; 
        } 
    } 
     
    print_r('<br/>DONE! You will be redirected to main page in 1 minute.'); 
    print_r('<br/>Total recipients count: ' . count($recipients)); 
     
    $secondsWait = 60; 
    echo '<meta http-equiv="refresh" content="'.$secondsWait.'">'; 
     
    die(); 
} 
?> 
 
 
<head> 
    <meta http-equiv="content-type" content="text/html; charset=UTF-8"> 
    <meta charset="utf-8"> 
    <title>XasTrO Mailer</title> 
    <link href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css" rel="stylesheet"> 
    <!--[if lt IE 9]> 
        <script src="//html5shim.googlecode.com/svn/trunk/html5.js"></script> 
    <![endif]--> 
</head> 
 
<div id="wrap"> 
    <div class="navbar navbar-default"> 
        <div class="container" style="width:90%;"> 
            <div class="navbar-header"> 
                <a class="navbar-brand" href="#">XasTrO Mailer</a> 
            </div> 
        </div> 
    </div> 
     
    <div class="container" style="width:90%;"> 
        <form method="POST" enctype="multipart/form-data"> 
        <div class="page-header" style="margin-top: 0px;"> 
            <h3>Mailing setup</h3> 
             
            <button type="submit" class="btn btn-primary btn-md" role="button" style="float:right;position:relative;top:-40px;">SEND FOR ALL RECIPIENTS</button> 
        </div> 
     
         
            <div class="col-md-9"> 
                <div class="col-md-6"> 
                    <label>From</label> 
                    <div class="input-group"> 
                        <span class="input-group-addon">@</span> 
                        <input name="from_email" type="email" class="form-control" placeholder="Please type sender e-mail" required> 
                    </div> 
                </div> 
                <div class="col-md-6"> 
                    <label>&nbsp;</label> 
                    <div class="input-group"> 
                        <span class="input-group-addon">Name</span> 
                        <input name="from_name" type="text" class="form-control" placeholder="Please type sender name" required> 
                    </div> 
                </div> 
                 
                <div class="clearfix"></div> 
                 
                <br/><br/> 
                <div class="col-md-12"> 
                    <label>Attachments</label> 
     
                    <div class="form-group"> 
                        <div class="input-group input-file"> 
                            <span class="input-group-btn"> 
                                <button class="btn btn-default btn-choose" type="button">Choose</button> 
                            </span> 
                            <input type="text" class="form-control" placeholder='Choose a file...' /> 
                            <span class="input-group-btn"> 
                             <button class="btn btn-warning btn-reset" type="button">Reset</button> 
                        </span> 
                        </div> 
                    </div> 
                </div> 
         
                <div class="clearfix"></div> 
                 
                <br/> 
                <div class="col-md-6"> 
                    <label>Subject letter</label> 
                    <div class="input-group"> 
                        <span class="input-group-addon">Subject</span> 
                        <input name="letter_subject" type="text" class="form-control" placeholder="Please type" required> 
                    </div> 
                </div> 
                <div class="col-md-6"> 
                    <label>Reply to (email)</label> 
                    <div class="input-group"> 
                        <span class="input-group-addon">@</span> 
                        <input name="letter_reply" type="email" class="form-control" placeholder="Please type reply-to e-mail"> 
                    </div> 
                </div> 
         
                <div class="clearfix"></div> 
                 
                <br/> 
                <div class="col-md-6"> 
                    <label>Message</label> 
                    <textarea name="letter_message" class="form-control" rows="10" required></textarea> 
                </div> 
                <div class="col-md-6"> 
                    <label>Recipients (each email on new line)</label> 
                    <textarea name="letter_recipients" class="form-control" rows="10" required></textarea> 
                </div> 
                 
                <div class="clearfix"></div> 
         
                <br/><br/> 
                <div class="col-md-6"> 
                    <label>Message type</label> 
                    <div class="radio"> 
                        <label> 
                            <input type="radio" name="type" id="typePlain" value="typePlain" checked> 
                            Plain text 
                        </label> 
                    </div> 
                    <div class="radio"> 
                        <label> 
                            <input type="radio" name="type" id="typeHtml" value="typeHtml"> 
                            HTML 
                        </label> 
                    </div> 
                </div> 
                <div class="col-md-6"> 
                    <label>Encoding</label> 
                    <div class="radio"> 
                        <label> 
                            <input type="radio" name="encode" id="encodeUtf8" value="encodeUtf8" checked> 
                            UTF-8 Encode 
                        </label> 
                    </div> 
                    <div class="radio"> 
                        <label> 
                            <input type="radio" name="encode" id="encodeIso" value="encodeIso"> 
                            ISO Encode 
                        </label> 
                    </div> 
                </div> 
            </div> 
            <div class="col-md-3"> 
     
                <div class="col-md-12"> 
                    <label>&nbsp;</label> 
                    <div class="panel panel-default"> 
                        <div class="panel-heading">SMTP</div> 
                        <div class="panel-body"> 
                            <label>Settings</label> 
                            <div class="col-md-12"> 
                                <div class="checkbox"> 
                                    <label><input id="smtp_on" name="smtp_on" type="checkbox">Use custom SMTP</label> 
                                </div> 
                            </div> 
     
                            <div class="clearfix"></div> 
     
                            <label>Host</label> 
                            <div class="col-md-12"> 
                                <div class="input-group"> 
                                    <span class="input-group-addon">HOST</span> 
                                    <input id="smtp_host" name="smtp_host" type="text" class="form-control" placeholder="Please type"> 
                                </div> 
                            </div> 
     
                            <br/> 
                            <div class="clearfix"></div> 
                            <br/> 
                             
                            <div class="col-md-12"> 
                                <div class="input-group"> 
                                    <span class="input-group-addon">PORT</span> 
                                    <input id="smtp_port" name="smtp_port" type="number" class="form-control" placeholder="Please type" value="587"> 
                                </div> 
                            </div> 
     
                            <br/> 
                            <div class="clearfix"></div> 
                            <br/> 
     
                            <div class="col-md-12"> 
                                <div class="input-group"> 
                                    <span class="input-group-addon">NAME</span> 
                                    <input id="smtp_username" name="smtp_username" type="text" class="form-control" placeholder="Please type"> 
                                </div> 
                            </div> 
     
                            <br/> 
                            <div class="clearfix"></div> 
                            <br/> 
     
                            <div class="col-md-12"> 
                                <div class="input-group"> 
                                    <span class="input-group-addon">PSWD</span> 
                                    <input id="smtp_password" name="smtp_password" type="password" class="form-control" placeholder="Please type"> 
                                </div> 
                            </div> 
     
                            <br/> 
                            <div class="clearfix"></div> 
                            <br/> 
     
                            <label>SMTP Secure</label> 
                            <div class="col-md-12"> 
                                <div class="radio"> 
                                    <label> 
                                        <input type="radio" name="smtp_secure" value="tls"> 
                                        TLS 
                                    </label> 
                                </div> 
                                <div class="radio"> 
                                    <label> 
                                        <input type="radio" name="smtp_secure" value="ssl"> 
                                        SSL 
                                    </label> 
                                </div> 
                            </div> 
                        </div> 
                    </div> 
                </div> 
                 
                <div class="clearfix"></div> 
                 
                <div class="col-md-12"> 
                    <label>&nbsp;</label> 
                    <div class="panel panel-default"> 
                        <div class="panel-heading">Instructions</div> 
                        <div class="panel-body"> 
                            <h4>Server Information</h4> 
                            <p>ServerIP : <?= $_SERVER['SERVER_ADDR']; ?></p> 
                             
                            <h4>HELP</h4> 
                            <p>#RECIPIENT# : [email protected]</p> 
                            <p>#FROM# : [email protected]</p> 
                            <p>#DATE# : 01/01/2019</p> 
                            <p>#TIME# : 11:40 PM</p> 
                            <p>#RANDOMSTRING# : (0-9, a-z)</p> 
                            <p>#RANDOMLETTERS# : (a-z)</p> 
                            <p>#RANDOMNUMBER# : (0-9)</p> 
                            <p>#RANDOMMD5# : Random MD5</p> 
                             
                            <h4>Example</h4> 
                            <p>Your e-mail: #RECIPIENT#</p> 
                            <p>Current time: #TIME#</p> 
                        </div> 
                    </div> 
                </div> 
            </div> 
        </form> 
    </div> 
</div> 
 
<div id="footer"> 
    <div class="container"> 
        <p class="text-muted credit">Developed by <a href="www.linkedin.com/in/nickkolesnikov" target="_blank">Nick Kolesnikov</a></p> 
    </div> 
</div> 
 
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<script type="text/javascript" src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script> 
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