Use ntp time sync at end of wifi activities

lib/hal/HalClock.cpp

@@ -3,6 +3,7 @@
 #include <Arduino.h>
 #include <Logging.h>
 #include <Preferences.h>
+#include <WiFi.h>
 #include <esp_private/esp_clk.h>
 #include <esp_sntp.h>
 #include <sys/time.h>
@@ -260,4 +261,17 @@ void formatLogTime(char* buf, size_t bufSize) {
   snprintf(buf, bufSize, "%02d:%02d:%02d", timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);
 }
 
+void wifiOff(bool skipNtpSync) {
+  if (!skipNtpSync && isApproximate() && WiFi.getMode() == WIFI_STA && WiFi.status() == WL_CONNECTED) {
+    syncNtp();
+  }
+  if (esp_sntp_enabled()) {
+    esp_sntp_stop();
+  }
+  WiFi.disconnect(false);
+  delay(100);
+  WiFi.mode(WIFI_OFF);
+  delay(100);
+}
+
 }  // namespace HalClock

lib/hal/HalClock.h

@@ -65,4 +65,9 @@ void formatTime(char* buf, size_t bufSize, bool use24h);
 /// synced, or an empty string if not.
 void formatLogTime(char* buf, size_t bufSize);
 
+/// Tear down WiFi cleanly.  When skipNtpSync is false (default) and the
+/// clock is approximate, performs an opportunistic NTP sync before
+/// disconnecting — essentially free since we already have a connection.
+void wifiOff(bool skipNtpSync = false);
+
 }  // namespace HalClock

src/activities/browser/OpdsBookBrowserActivity.cpp

@@ -2,6 +2,7 @@
 
 #include <Epub.h>
 #include <GfxRenderer.h>
+#include <HalClock.h>
 #include <I18n.h>
 #include <Logging.h>
 #include <OpdsStream.h>
@@ -39,8 +40,7 @@ void OpdsBookBrowserActivity::onEnter() {
 void OpdsBookBrowserActivity::onExit() {
   Activity::onExit();
 
-  // Turn off WiFi when exiting
-  WiFi.mode(WIFI_OFF);
+  HalClock::wifiOff();
 
   entries.clear();
   navigationHistory.clear();

src/activities/network/CrossPointWebServerActivity.cpp

@@ -3,6 +3,7 @@
 #include <DNSServer.h>
 #include <ESPmDNS.h>
 #include <GfxRenderer.h>
+#include <HalClock.h>
 #include <I18n.h>
 #include <WiFi.h>
 #include <esp_task_wdt.h>
@@ -86,15 +87,12 @@ void CrossPointWebServerActivity::onExit() {
   if (isApMode) {
     LOG_DBG("WEBACT", "Stopping WiFi AP...");
     WiFi.softAPdisconnect(true);
+    delay(30);
+    WiFi.mode(WIFI_OFF);
+    delay(30);
   } else {
-    LOG_DBG("WEBACT", "Disconnecting WiFi (graceful)...");
-    WiFi.disconnect(false);  // false = don't erase credentials, send disconnect frame
+    HalClock::wifiOff();
   }
-  delay(30);  // Allow disconnect frame to be sent
-
-  LOG_DBG("WEBACT", "Setting WiFi mode OFF...");
-  WiFi.mode(WIFI_OFF);
-  delay(30);  // Allow WiFi hardware to power down
 
   LOG_DBG("WEBACT", "Free heap at onExit end: %d bytes", ESP.getFreeHeap());
 }

src/activities/reader/KOReaderSyncActivity.cpp

@@ -5,7 +5,6 @@
 #include <I18n.h>
 #include <Logging.h>
 #include <WiFi.h>
-#include <esp_sntp.h>
 
 #include "KOReaderCredentialStore.h"
 #include "KOReaderDocumentId.h"
@@ -14,18 +13,6 @@
 #include "components/UITheme.h"
 #include "fontIds.h"
 
-namespace {
-void wifiOff() {
-  if (esp_sntp_enabled()) {
-    esp_sntp_stop();
-  }
-  WiFi.disconnect(false);
-  delay(100);
-  WiFi.mode(WIFI_OFF);
-  delay(100);
-}
-}  // namespace
-
 void KOReaderSyncActivity::onWifiSelectionComplete(const bool success) {
   if (!success) {
     LOG_DBG("KOSync", "WiFi connection failed, exiting");
@@ -149,7 +136,7 @@ void KOReaderSyncActivity::performUpload() {
   const auto result = KOReaderSyncClient::updateProgress(progress);
 
   if (result != KOReaderSyncClient::OK) {
-    wifiOff();
+    HalClock::wifiOff(true);
     {
       RenderLock lock(*this);
       state = SYNC_FAILED;
@@ -159,7 +146,7 @@ void KOReaderSyncActivity::performUpload() {
     return;
   }
 
-  wifiOff();
+  HalClock::wifiOff(true);
   {
     RenderLock lock(*this);
     state = UPLOAD_COMPLETE;
@@ -193,7 +180,7 @@ void KOReaderSyncActivity::onEnter() {
 void KOReaderSyncActivity::onExit() {
   Activity::onExit();
 
-  wifiOff();
+  HalClock::wifiOff(true);
 }
 
 void KOReaderSyncActivity::render(RenderLock&&) {

src/activities/settings/DetectTimezoneActivity.cpp

@@ -6,7 +6,6 @@
 #include <I18n.h>
 #include <Logging.h>
 #include <WiFi.h>
-#include <esp_sntp.h>
 
 #include <string>
 
@@ -188,15 +187,6 @@ bool detectTimezoneSetting(uint8_t& outSetting, std::string& outIana, bool& outD
   return true;
 }
 
-void wifiOff() {
-  if (esp_sntp_enabled()) {
-    esp_sntp_stop();
-  }
-  WiFi.disconnect(false);
-  delay(100);
-  WiFi.mode(WIFI_OFF);
-  delay(100);
-}
 }  // namespace
 
 void DetectTimezoneActivity::onEnter() {
@@ -219,7 +209,7 @@ void DetectTimezoneActivity::onEnter() {
 
 void DetectTimezoneActivity::onExit() {
   Activity::onExit();
-  wifiOff();
+  HalClock::wifiOff();
 }
 
 void DetectTimezoneActivity::onWifiSelectionComplete(bool success) {
@@ -254,7 +244,7 @@ void DetectTimezoneActivity::performDetect() {
     state = FAILED;
   }
 
-  wifiOff();
+  HalClock::wifiOff();
   requestUpdate();
 }
 

src/activities/settings/KOReaderAuthActivity.cpp

@@ -1,6 +1,7 @@
 #include "KOReaderAuthActivity.h"
 
 #include <GfxRenderer.h>
+#include <HalClock.h>
 #include <I18n.h>
 #include <WiFi.h>
 
@@ -65,11 +66,7 @@ void KOReaderAuthActivity::onEnter() {
 void KOReaderAuthActivity::onExit() {
   Activity::onExit();
 
-  // Turn off wifi
-  WiFi.disconnect(false);
-  delay(100);
-  WiFi.mode(WIFI_OFF);
-  delay(100);
+  HalClock::wifiOff();
 }
 
 void KOReaderAuthActivity::render(RenderLock&&) {

src/activities/settings/OtaUpdateActivity.cpp

@@ -1,6 +1,7 @@
 #include "OtaUpdateActivity.h"
 
 #include <GfxRenderer.h>
+#include <HalClock.h>
 #include <I18n.h>
 #include <WiFi.h>
 
@@ -66,11 +67,7 @@ void OtaUpdateActivity::onEnter() {
 void OtaUpdateActivity::onExit() {
   Activity::onExit();
 
-  // Turn off wifi
-  WiFi.disconnect(false);  // false = don't erase credentials, send disconnect frame
-  delay(100);              // Allow disconnect frame to be sent
-  WiFi.mode(WIFI_OFF);
-  delay(100);  // Allow WiFi hardware to fully power down
+  HalClock::wifiOff();
 }
 
 void OtaUpdateActivity::render(RenderLock&&) {

src/activities/settings/SyncTimeActivity.cpp

@@ -5,7 +5,6 @@
 #include <I18n.h>
 #include <Logging.h>
 #include <WiFi.h>
-#include <esp_sntp.h>
 
 #include "CrossPointSettings.h"
 #include "MappedInputManager.h"
@@ -13,18 +12,6 @@
 #include "components/UITheme.h"
 #include "fontIds.h"
 
-namespace {
-void wifiOff() {
-  if (esp_sntp_enabled()) {
-    esp_sntp_stop();
-  }
-  WiFi.disconnect(false);
-  delay(100);
-  WiFi.mode(WIFI_OFF);
-  delay(100);
-}
-}  // namespace
-
 void SyncTimeActivity::onEnter() {
   Activity::onEnter();
 
@@ -45,7 +32,7 @@ void SyncTimeActivity::onEnter() {
 
 void SyncTimeActivity::onExit() {
   Activity::onExit();
-  wifiOff();
+  HalClock::wifiOff(true);
 }
 
 void SyncTimeActivity::onWifiSelectionComplete(bool success) {
@@ -68,7 +55,7 @@ void SyncTimeActivity::onWifiSelectionCancelled() { finish(); }
 
 void SyncTimeActivity::performSync() {
   bool ok = HalClock::syncNtp();
-  wifiOff();
+  HalClock::wifiOff(true);
 
   state = ok ? SUCCESS : FAILED;
   requestUpdate();