remove usage of nsyslog-parser-2

this module is somehow parsing the syslog incorrectly causing
incorrect directories being created in the logs directory
(since appName got parsed incorrectly)

syslog.js

@@ -12,11 +12,33 @@ const debug = require('debug')('syslog:server'),
     net = require('net'),
     path = require('path'),
     paths = require('./src/paths.js'),
-    parser = require('nsyslog-parser-2'),
     util = require('util');
 
 let gServer = null;
 
+// https://docs.docker.com/engine/logging/drivers/syslog/
+// example: <34>1 2023-09-07T14:33:22Z myhost myapp 1234 5678 [exampleSDID@32473 iut="3" eventSource="Application"] An example message
+function parseRFC5424Message(message) {
+    const syslogRegex = /^<(\d+)>(\d+) (\S+) (\S+) (\S+) (\S+) (\S+) (?:\[(.*?)\])?(.*)$/;
+
+    const match = message.match(syslogRegex);
+    if (!match) return null;
+
+    const [, pri, version, timestamp, hostname, appName, procId, msgId, structuredData, msg] = match;
+
+    return {
+        pri: parseInt(pri, 10),          // priority
+        version: parseInt(version, 10),  // version
+        timestamp,                       // timestamp
+        hostname,                        // hostname
+        appName,                         // app name
+        procId,                          // process ID
+        msgId,                           // message ID
+        structuredData: structuredData ? structuredData : null,  // structured data (if present)
+        msg: msg ? msg.trim() : null     // message
+    };
+}
+
 async function start() {
     debug('==========================================');
     debug('          Cloudron Syslog Daemon          ');
@@ -32,11 +54,8 @@ async function start() {
         socket.on('data', function (msg) {
             const lines = msg.toString().split('\n'); // may be multiline data
 
-            lines.forEach(function (msg) {
-                if (!msg) return;
-
-                const info = parser(msg);
-
+            for (const msg of lines) {
+                const info = parseRFC5424Message(msg);
                 if (!info || !info.appName) return debug('Ignore unknown app log:', msg);
 
                 // remove line breaks to avoid holes in the log file
@@ -47,15 +66,15 @@ async function start() {
 
                 try {
                     fs.mkdirSync(appLogDir, { recursive: true });
-                    fs.appendFileSync(`${appLogDir}/app.log`, info.ts.toISOString() + ' ' + message + '\n');
+                    fs.appendFileSync(`${appLogDir}/app.log`, `${info.timestamp} ${message}\n}`);
                 } catch (error) {
-                    console.error(error);
+                    debug(error);
                 }
-            });
+            }
         });
 
         socket.on('error', function (error) {
-            console.error(`socket error: ${error}`);
+            debug(`socket error: ${error}`);
         });
     });