From 6dd0020bf6f9c555a037cd4c681a6c9e934f5e29 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Fri, 17 Oct 2025 09:39:51 -1000
Subject: [PATCH] [api][time] Refactor timezone update logic for cleaner code

---
 esphome/components/api/api_connection.cpp | 9 ++-------
 esphome/components/time/real_time_clock.h | 8 ++++++++
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/esphome/components/api/api_connection.cpp b/esphome/components/api/api_connection.cpp
index 1f3456a205..39bcb83cfb 100644
--- a/esphome/components/api/api_connection.cpp
+++ b/esphome/components/api/api_connection.cpp
@@ -1081,13 +1081,8 @@ void APIConnection::on_get_time_response(const GetTimeResponse &value) {
     homeassistant::global_homeassistant_time->set_epoch_time(value.epoch_seconds);
 #ifdef USE_TIME_TIMEZONE
     if (value.timezone_len > 0) {
-      const std::string &current_tz = homeassistant::global_homeassistant_time->get_timezone();
-      // Compare without allocating a string
-      if (current_tz.length() != value.timezone_len ||
-          memcmp(current_tz.c_str(), value.timezone, value.timezone_len) != 0) {
-        homeassistant::global_homeassistant_time->set_timezone(
-            std::string(reinterpret_cast<const char *>(value.timezone), value.timezone_len));
-      }
+      homeassistant::global_homeassistant_time->set_timezone(reinterpret_cast<const char *>(value.timezone),
+                                                             value.timezone_len);
     }
 #endif
   }
diff --git a/esphome/components/time/real_time_clock.h b/esphome/components/time/real_time_clock.h
index 4b98a88975..7e60bbd234 100644
--- a/esphome/components/time/real_time_clock.h
+++ b/esphome/components/time/real_time_clock.h
@@ -27,6 +27,14 @@ class RealTimeClock : public PollingComponent {
     this->apply_timezone_();
   }
 
+  /// Set the time zone from raw buffer, only if it differs from the current one.
+  void set_timezone(const char *tz, size_t len) {
+    if (this->timezone_.length() != len || memcmp(this->timezone_.c_str(), tz, len) != 0) {
+      this->timezone_.assign(tz, len);
+      this->apply_timezone_();
+    }
+  }
+
   /// Get the time zone currently in use.
   std::string get_timezone() { return this->timezone_; }
 #endif