Display error reason on ntp time sync fail

lib/hal/HalClock.cpp

@@ -377,7 +377,32 @@ void applyTimezone(uint8_t timeZoneSetting) {
   LOG_DBG("CLK", "Timezone applied: %s", TIMEZONES[index].tz);
 }
 
-bool syncNtp() {
+static const char* sntpStatusName(sntp_sync_status_t status) {
+  switch (status) {
+    case SNTP_SYNC_STATUS_RESET:
+      return "reset";
+    case SNTP_SYNC_STATUS_IN_PROGRESS:
+      return "in progress";
+    case SNTP_SYNC_STATUS_COMPLETED:
+      return "completed";
+    default:
+      return "unknown";
+  }
+}
+
+bool syncNtp(char* errorBuf, size_t errorBufSize) {
+  if (errorBuf && errorBufSize > 0) {
+    errorBuf[0] = '\0';
+  }
+
+  if (WiFi.status() != WL_CONNECTED) {
+    if (errorBuf && errorBufSize > 0) {
+      snprintf(errorBuf, errorBufSize, "WiFi disconnected");
+    }
+    LOG_ERR("CLK", "NTP sync failed: WiFi disconnected");
+    return false;
+  }
+
   time_t preSyncTime = time(nullptr);
   time_t prevSyncTime = nvsReadSyncTime();
   float prevSyncTemp = nvsReadLastSyncTemp();
@@ -398,7 +423,11 @@ bool syncNtp() {
   }
 
   if (retry >= maxRetries) {
-    LOG_ERR("CLK", "NTP sync timeout");
+    const char* statusName = sntpStatusName(sntp_get_sync_status());
+    if (errorBuf && errorBufSize > 0) {
+      snprintf(errorBuf, errorBufSize, "NTP timeout (%s)", statusName);
+    }
+    LOG_ERR("CLK", "NTP sync timeout (%s)", statusName);
     return false;
   }
 
@@ -453,6 +482,8 @@ bool syncNtp() {
   return true;
 }
 
+bool syncNtp() { return syncNtp(nullptr, 0); }
+
 void saveBeforeSleep(bool keepLpAlive) {
   if (!isSynced()) {
     return;

lib/hal/HalClock.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <cstddef>
 #include <cstdint>
 #include <ctime>
 
@@ -30,6 +31,10 @@ namespace HalClock {
 /// Returns true if the sync succeeded.
 bool syncNtp();
 
+/// Same as syncNtp(), but fills `errorBuf` with a short failure reason when
+/// the sync fails.
+bool syncNtp(char* errorBuf, size_t errorBufSize);
+
 /// Apply timezone/DST rules via the POSIX TZ string for the given setting.
 void applyTimezone(uint8_t timeZoneSetting);
 

src/activities/settings/SyncTimeActivity.cpp

@@ -7,6 +7,7 @@
 #include <WiFi.h>
 
 #include <cstdlib>
+#include <string>
 
 #include "CrossPointSettings.h"
 #include "MappedInputManager.h"
@@ -93,8 +94,9 @@ void SyncTimeActivity::performSync() {
   hadTimeBeforeSync = HalClock::isSynced();
   preSyncTime = hadTimeBeforeSync ? time(nullptr) : 0;
   prevSyncTime = HalClock::lastSyncTime();
+  syncErrorMsg[0] = '\0';
 
-  bool ok = HalClock::syncNtp();
+  bool ok = HalClock::syncNtp(syncErrorMsg, sizeof(syncErrorMsg));
 
   if (ok && hadTimeBeforeSync) {
     driftSeconds = (int32_t)(time(nullptr) - preSyncTime);
@@ -184,10 +186,17 @@ void SyncTimeActivity::render(RenderLock&&) {
   }
 
   if (state == FAILED) {
-    renderer.drawCenteredText(UI_10_FONT_ID, bodyRect.y + bodyRect.height / 2, tr(STR_TIME_SYNC_FAILED), true,
+    int y = bodyRect.y + bodyRect.height / 2 - 10;
-                              EpdFontFamily::BOLD);
+    renderer.drawCenteredText(UI_10_FONT_ID, y, tr(STR_TIME_SYNC_FAILED), true, EpdFontFamily::BOLD);
 
-    const auto labels = mappedInput.mapLabels(tr(STR_BACK), "", "", "");
+    if (syncErrorMsg[0] != '\0') {
+      y += 25;
+      const std::string errorText =
+          renderer.truncatedText(UI_10_FONT_ID, syncErrorMsg, bodyRect.width, EpdFontFamily::REGULAR);
+      renderer.drawCenteredText(UI_10_FONT_ID, y, errorText.c_str(), true, EpdFontFamily::REGULAR);
+    }
+
+    const auto labels = mappedInput.mapLabels(tr(STR_BACK), tr(STR_RETRY), "", "");
     GUI.drawButtonHints(renderer, labels.btn1, labels.btn2, labels.btn3, labels.btn4);
     renderer.displayBuffer();
     return;
@@ -198,6 +207,14 @@ void SyncTimeActivity::loop() {
   if (state == SUCCESS || state == FAILED) {
     if (mappedInput.wasPressed(MappedInputManager::Button::Back)) {
       finish();
+      return;
+    }
+
+    if (state == FAILED && mappedInput.wasPressed(MappedInputManager::Button::Confirm)) {
+      RenderLock lock(*this);
+      state = SYNCING;
+      requestUpdateAndWait();
+      performSync();
     }
   }
 }

src/activities/settings/SyncTimeActivity.h

@@ -19,6 +19,7 @@ class SyncTimeActivity final : public Activity {
   time_t prevSyncTime = 0;
   int32_t driftSeconds = 0;
   bool hadTimeBeforeSync = false;
+  char syncErrorMsg[64] = {};
   void onWifiSelectionComplete(bool success);
   void onWifiSelectionCancelled();
   void performSync();