From a7693df92c8d0b1f250c02732f60130b67be9eea Mon Sep 17 00:00:00 2001
From: Alex Ballas <alex@ballas.org>
Date: Tue, 3 Jun 2025 02:28:14 +0300
Subject: [PATCH] fix: the screen doesn't dim or turn off

* Fix for #531

Fix for https://github.com/jetkvm/kvm/issues/531

* typo

* Skip processing if lease hasn't changed to avoid unnecessary wake-ups

* Add comment to clarify the need to stop the tickers
---
 display.go                | 15 +++++++++++----
 internal/udhcpc/udhcpc.go |  7 +++++++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/display.go b/display.go
index 2a22351..cf1a0cc 100644
--- a/display.go
+++ b/display.go
@@ -339,10 +339,18 @@ func startBacklightTickers() {
 		return
 	}
 
-	if dimTicker == nil && config.DisplayDimAfterSec != 0 {
+	// Stop existing tickers to prevent multiple active instances on repeated calls
+	if dimTicker != nil {
+		dimTicker.Stop()
+	}
+
+	if offTicker != nil {
+		offTicker.Stop()
+	}
+
+	if config.DisplayDimAfterSec != 0 {
 		displayLogger.Info().Msg("dim_ticker has started")
 		dimTicker = time.NewTicker(time.Duration(config.DisplayDimAfterSec) * time.Second)
-		defer dimTicker.Stop()
 
 		go func() {
 			for { //nolint:staticcheck
@@ -354,10 +362,9 @@ func startBacklightTickers() {
 		}()
 	}
 
-	if offTicker == nil && config.DisplayOffAfterSec != 0 {
+	if config.DisplayOffAfterSec != 0 {
 		displayLogger.Info().Msg("off_ticker has started")
 		offTicker = time.NewTicker(time.Duration(config.DisplayOffAfterSec) * time.Second)
-		defer offTicker.Stop()
 
 		go func() {
 			for { //nolint:staticcheck
diff --git a/internal/udhcpc/udhcpc.go b/internal/udhcpc/udhcpc.go
index 70ac1b8..128ea66 100644
--- a/internal/udhcpc/udhcpc.go
+++ b/internal/udhcpc/udhcpc.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"reflect"
 	"time"
 
 	"github.com/fsnotify/fsnotify"
@@ -149,6 +150,12 @@ func (c *DHCPClient) loadLeaseFile() error {
 	}
 
 	isFirstLoad := c.lease == nil
+
+	// Skip processing if lease hasn't changed to avoid unnecessary wake-ups.
+	if reflect.DeepEqual(c.lease, lease) {
+		return nil
+	}
+
 	c.lease = lease
 
 	if lease.IPAddress == nil {