Revert "Merge pull request #135 from server-status-project/master"

This reverts commit 8d571547f5, reversing
changes made to e96df7015e.

classes/mailer.php

@@ -0,0 +1,174 @@
+<?php
+
+/**
+ * Class that encapsulates everything that can be done with email
+ */
+
+use PHPMailer\PHPMailer\PHPMailer;  // Inclusion of namespace will not cause any issue even if PHPMailer is not used
+use PHPMailer\PHPMailer\Exception;
+
+// TODO Any other way to handle this include? Should we just do the include form each index.php?
+if (file_exists("libs/php_idn/idna.php")) {
+    require_once("libs/php_idn/idna.php");
+} else {
+    // Include for Admin section
+    require_once("../libs/php_idn/idna.php");
+}
+
+class Mailer {
+
+    public function __construct(){
+
+    }
+
+    /**
+     * Generic function to submit mail messages via mail og PHPmailer()
+     * @param String $to Email address to which mail should be sent
+     * @param String $message Body of email
+     * @param boolean $html Set to true if we are sending HTML Mailer
+     * @return boolean True if success
+     */
+    public function send_mail($to, $subject, $message, $html = true) {
+        // TODO -Handle $to as an array in order to send to muliple recipients without having
+        //       to call the entire send_mail function over and over..
+
+        $content_type  = ($html) ? 'text/html' : 'text/plain';
+
+        // Convert IDN/punycode domain to ascii
+        // TODO Handle IDN in left hand side of email address
+        if ( $this->is_utf8($to) ) {
+            $elements  = explode('@', $to);
+            $domainpart = EncodePunycodeIDN(array_pop($elements));  // Convert domain part to ascii
+            $to = $elements[0] . '@' . $domainpart;  // Reassemble tge full email address
+        }
+
+        // Send using PHP mailer if it is enabled
+        if ( PHP_MAILER ) {
+            require_once(PHP_MAILER_PATH .'/Exception.php'); /* Exception class. */
+            require_once(PHP_MAILER_PATH .'/PHPMailer.php'); /* The main PHPMailer class. */
+
+            if ( PHP_MAILER_SMTP ) {
+                require_once(PHP_MAILER_PATH .'/SMTP.php');  /* SMTP class, needed if you want to use SMTP. */
+            }
+
+            $phpmail = new PHPMailer(false);
+
+            $phpmail->setFrom(MAILER_ADDRESS, MAILER_NAME);
+            $phpmail->addReplyTo(MAILER_ADDRESS, MAILER_NAME);
+            //$phpmail->Debugoutput = error_log;
+
+            // Define SMTP parameters if enabled
+            if ( PHP_MAILER_SMTP ) {
+
+                $phpmail->isSMTP();
+                $phpmail->Host = PHP_MAILER_HOST;
+                $phpmail->Port = PHP_MAILER_PORT;
+                $phpmail->SMTPSecure = PHP_MAILER_SECURE;
+                //$phpmail->SMTPDebug = 2; // Enable for debugging
+
+                // Handle authentication for SMTP if enabled
+                if ( !empty(PHP_MAILER_USER) ) {
+                    $phpmail->SMTPAuth = true;
+                    $phpmail->Username = PHP_MAILER_USER;
+                    $phpmail->Password = PHP_MAILER_PASS;
+                }
+            }
+
+            $phpmail->addAddress($to);
+            $phpmail->Subject = $subject;
+            // Send HMTL mail
+            if ( $html ) {
+                $phpmail->msgHtml($message);
+                $phpmail->AltBody = $this->convert_html_to_plain_txt($message, false);
+            } else {
+                $phpmail->Body = $message;  // Send plain text
+            }
+
+            $phpmail->isHtml($html);    // use htmlmail if enabled
+            if ( ! $phpmail->send() ) {
+                // TODO Log error message $phpmail->ErrorInfo;
+                return false;
+            }
+            return true;
+
+        } else {
+            // Use standard PHP mail() function
+            $headers = "Content-Type: $content_type; \"charset=utf-8\" ".PHP_EOL;
+            $headers .= "MIME-Version: 1.0 ".PHP_EOL;
+            $headers .= "From: ".MAILER_NAME.' <'.MAILER_ADDRESS.'>'.PHP_EOL;
+            $headers .= "Reply-To: ".MAILER_NAME.' <'.MAILER_ADDRESS.'>'.PHP_EOL;
+
+            mail($to, $subject, $message, $headers);
+            // TODO log error message if mail fails
+            return true;
+        }
+
+    }
+    /**
+     * Tries to verify the domain using dns request against an MX record of the domain part
+     * of the passed email address. The code also handles IDN/Punycode formatted addresses which
+     * contains utf8 characters.
+     * Original code from https://stackoverflow.com/questions/19261987/how-to-check-if-an-email-address-is-real-or-valid-using-php/19262381
+     * @param String $email Email address to check
+     * @return boolean True if MX record exits, false if otherwise
+     */
+    public function verify_domain($email){
+        // TODO - Handle idn/punycode domain names without being dependent on PHP native libs.
+        $domain = explode('@', $email);
+        $domain = EncodePunycodeIDN(array_pop($domain).'.');  // Add dot at end of domain to avoid local domain lookups
+        syslog(1,$domain);
+        return checkdnsrr($domain, 'MX');
+    }
+
+
+    /**
+     * Check if string contains non-english characters (detect IDN/Punycode enabled domains)
+     * Original code from: https://stackoverflow.com/questions/13120475/detect-non-english-chars-in-a-string
+     * @param String $str String to check for extended characters
+     * @return boolean True if extended characters, false otherwise
+     */
+    public function is_utf8($str)
+    {
+        if (strlen($str) == strlen(utf8_decode($str))) {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Takes the input from an HTML email and convert it to plain text
+     * This is commonly used when sending HTML emails as a backup for email clients who can only view, or who choose to only view,
+     * Original code from https://github.com/DukeOfMarshall/PHP---JSON-Email-Verification/blob/master/EmailVerify.class.php
+     * plain text emails
+     * @param string $content The body part of the email to convert to plain text.
+     * @param boolean $remove_links Set to true if links should be removed from email
+     * @return String pain text version
+     */
+    public function convert_html_to_plain_txt($content, $remove_links=false){
+        // TODO does not handle unsubscribe/manage subscription text very well.
+        // Replace HTML line breaks with text line breaks
+        $plain_text = str_ireplace(array("<br>","<br />"), "\n\r", $content);
+
+        // Remove the content between the tags that wouldn't normally get removed with the strip_tags function
+        $plain_text = preg_replace(array('@<head[^>]*?>.*?</head>@siu',
+            '@<style[^>]*?>.*?</style>@siu',
+            '@<script[^>]*?.*?</script>@siu',
+            '@<noscript[^>]*?.*?</noscript>@siu',
+        ), "", $plain_text); // Remove everything from between the tags that doesn't get removed with strip_tags function
+
+        // If the user has chosen to preserve the addresses from links
+        if(!$remove_links){
+            $plain_text = strip_tags(preg_replace('/<a href="(.*)">/', ' $1 ', $plain_text));
+        }
+
+        // Remove HTML spaces
+        $plain_text = str_replace("&nbsp;", "", $plain_text);
+
+        // Replace multiple line breaks with a single line break
+        $plain_text = preg_replace("/(\s){3,}/","\r\n\r\n",trim($plain_text));
+
+        return $plain_text;
+    }
+
+}