Enhance installer to detect existing installations and update seamlessly

modules/service-setup-module.sh

@@ -33,14 +33,72 @@ function setup_service() {
     return 1
   fi
   
-  # Create backup of existing service file if it exists
-  if [ -f "/etc/systemd/system/$SERVICE_NAME.service" ]; then
-    backup_file "/etc/systemd/system/$SERVICE_NAME.service"
-  fi
-  
-  # Create systemd service file
+  # Check if service file already exists
   SERVICE_FILE="/etc/systemd/system/$SERVICE_NAME.service"
-  cat > "$SERVICE_FILE" << EOF
+  if [ -f "$SERVICE_FILE" ] && [ "$IS_UPDATE" = true ]; then
+    log "INFO" "Service file already exists. Preserving existing service configuration."
+    
+    # Extract existing JWT_SECRET if present to maintain session consistency
+    EXISTING_JWT_SECRET=$(grep "Environment=JWT_SECRET=" "$SERVICE_FILE" | cut -d'=' -f3)
+    
+    # Extract existing PORT if it differs from the configured one
+    EXISTING_PORT=$(grep "Environment=PORT=" "$SERVICE_FILE" | cut -d'=' -f3)
+    if [ -n "$EXISTING_PORT" ] && [ "$EXISTING_PORT" != "$PORT" ]; then
+      log "INFO" "Using existing port configuration: $EXISTING_PORT"
+      PORT=$EXISTING_PORT
+    fi
+    
+    # Create backup of existing service file
+    backup_file "$SERVICE_FILE"
+    
+    # Update the service file while preserving key settings
+    cat > "$SERVICE_FILE" << EOF
+[Unit]
+Description=Transmission RSS Manager
+After=network.target transmission-daemon.service
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=$USER
+WorkingDirectory=$INSTALL_DIR
+ExecStart=/usr/bin/node $INSTALL_DIR/server.js
+Restart=always
+RestartSec=10
+StandardOutput=journal
+StandardError=journal
+Environment=PORT=$PORT
+Environment=NODE_ENV=production
+Environment=DEBUG_ENABLED=false
+Environment=LOG_FILE=$INSTALL_DIR/logs/transmission-rss-manager.log
+EOF
+
+    # Preserve the existing JWT_SECRET if available
+    if [ -n "$EXISTING_JWT_SECRET" ]; then
+      echo "Environment=JWT_SECRET=$EXISTING_JWT_SECRET" >> "$SERVICE_FILE"
+    else
+      echo "# Generate a random JWT secret for security" >> "$SERVICE_FILE"
+      echo "Environment=JWT_SECRET=$(openssl rand -hex 32)" >> "$SERVICE_FILE"
+    fi
+
+    # Close the service file definition
+    cat >> "$SERVICE_FILE" << EOF
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+  else
+    # For fresh installations, create a new service file
+    log "INFO" "Creating new service file"
+    
+    # Create backup of existing service file if it exists
+    if [ -f "$SERVICE_FILE" ]; then
+      backup_file "$SERVICE_FILE"
+    fi
+    
+    # Create systemd service file
+    cat > "$SERVICE_FILE" << EOF
 [Unit]
 Description=Transmission RSS Manager
 After=network.target transmission-daemon.service
@@ -65,6 +123,7 @@ Environment=JWT_SECRET=$(openssl rand -hex 32)
 [Install]
 WantedBy=multi-user.target
 EOF
+  fi
 
   # Create logs directory
   mkdir -p "$INSTALL_DIR/logs"
@@ -146,6 +205,9 @@ server {
 }
 EOF
 
+  log "INFO" "Nginx configured to proxy connections from port 80 to port $PORT"
+  log "INFO" "You can access Transmission RSS Manager at http://your-server-ip/ (port 80) via Nginx"
+
   # Check if Debian/Ubuntu style (need symlink between available and enabled)
   if [ "$NGINX_AVAILABLE_DIR" != "$NGINX_ENABLED_DIR" ]; then
     # Create symbolic link to enable the site (if it doesn't already exist)
@@ -167,7 +229,10 @@ EOF
   # Check for port conflicts
   if ss -lnt | grep ":$PORT " &> /dev/null; then
     log "WARN" "Port $PORT is already in use. This may cause conflicts with the service."
-    log "WARN" "Consider changing the port if you encounter issues."
+    log "WARN" "The service will fail to start. Please stop any service using port $PORT and try again."
+  else
+    log "INFO" "You can access the web interface at: http://localhost:$PORT or http://your-server-ip:$PORT"
+    log "INFO" "You may need to configure your firewall to allow access to port $PORT"
   fi
   
   # Reload systemd