Display drifitng stats

lib/I18n/translations/english.yaml

@@ -112,6 +112,8 @@ STR_SYNCING_CLOCK: "Syncing clock..."
 STR_DETECTING_TIMEZONE: "Detecting timezone..."
 STR_TIME_SYNCED: "Time synced"
 STR_TIME_SYNC_FAILED: "Time sync failed"
+STR_CLOCK_DRIFT: "Drift: %s"
+STR_LAST_NTP_SYNC: "Last sync: %s"
 STR_TIMEZONE_DETECTED: "Timezone detected"
 STR_TIMEZONE_DETECT_FAILED: "Timezone detect failed"
 STR_DST_ACTIVE: "DST: active"

lib/hal/HalClock.cpp

@@ -227,6 +227,8 @@ bool isSynced() {
 
 bool isApproximate() { return clockApproximate; }
 
+time_t lastSyncTime() { return nvsReadSyncTime(); }
+
 void formatTime(char* buf, size_t bufSize, bool use24h) {
   if (!isSynced()) {
     snprintf(buf, bufSize, "--:--");

lib/hal/HalClock.h

@@ -55,6 +55,10 @@ bool isSynced();
 /// may have drifted.  Cleared on NTP sync.
 bool isApproximate();
 
+/// Returns the epoch of the last successful NTP sync (from NVS), or 0 if
+/// no sync has ever been recorded.
+time_t lastSyncTime();
+
 /// Format the current time for display.  Returns "--:--" if the clock was
 /// never synced, prefixes with "~" if approximate.
 /// When use24h is false, formats as "2:05pm" / "12:30am".

src/activities/settings/SyncTimeActivity.cpp

@@ -6,12 +6,48 @@
 #include <Logging.h>
 #include <WiFi.h>
 
+#include <cstdlib>
+
 #include "CrossPointSettings.h"
 #include "MappedInputManager.h"
 #include "activities/network/WifiSelectionActivity.h"
 #include "components/UITheme.h"
 #include "fontIds.h"
 
+static void formatDuration(char* buf, size_t bufSize, int32_t totalSeconds) {
+  const char* sign = totalSeconds < 0 ? "-" : "+";
+  int32_t abs = totalSeconds < 0 ? -totalSeconds : totalSeconds;
+
+  int32_t days = abs / 86400;
+  int32_t hours = (abs % 86400) / 3600;
+  int32_t mins = (abs % 3600) / 60;
+  int32_t secs = abs % 60;
+
+  if (days > 0) {
+    snprintf(buf, bufSize, "%s%ldd %ldh %ldm", sign, (long)days, (long)hours, (long)mins);
+  } else if (hours > 0) {
+    snprintf(buf, bufSize, "%s%ldh %ldm %lds", sign, (long)hours, (long)mins, (long)secs);
+  } else if (mins > 0) {
+    snprintf(buf, bufSize, "%s%ldm %lds", sign, (long)mins, (long)secs);
+  } else {
+    snprintf(buf, bufSize, "%s%lds", sign, (long)secs);
+  }
+}
+
+static void formatElapsed(char* buf, size_t bufSize, int32_t totalSeconds) {
+  int32_t days = totalSeconds / 86400;
+  int32_t hours = (totalSeconds % 86400) / 3600;
+  int32_t mins = (totalSeconds % 3600) / 60;
+
+  if (days > 0) {
+    snprintf(buf, bufSize, "%ldd %ldh ago", (long)days, (long)hours);
+  } else if (hours > 0) {
+    snprintf(buf, bufSize, "%ldh %ldm ago", (long)hours, (long)mins);
+  } else {
+    snprintf(buf, bufSize, "%ldm ago", (long)mins);
+  }
+}
+
 void SyncTimeActivity::onEnter() {
   Activity::onEnter();
 
@@ -54,7 +90,16 @@ void SyncTimeActivity::onWifiSelectionComplete(bool success) {
 void SyncTimeActivity::onWifiSelectionCancelled() { finish(); }
 
 void SyncTimeActivity::performSync() {
+  hadTimeBeforeSync = HalClock::isSynced();
+  preSyncTime = hadTimeBeforeSync ? time(nullptr) : 0;
+  prevSyncTime = HalClock::lastSyncTime();
+
   bool ok = HalClock::syncNtp();
+
+  if (ok && hadTimeBeforeSync) {
+    driftSeconds = (int32_t)(time(nullptr) - preSyncTime);
+  }
+
   HalClock::wifiOff(true);
 
   state = ok ? SUCCESS : FAILED;
@@ -76,7 +121,8 @@ void SyncTimeActivity::render(RenderLock&&) {
   }
 
   if (state == SUCCESS) {
-    renderer.drawCenteredText(UI_10_FONT_ID, pageHeight / 2 - 20, tr(STR_TIME_SYNCED), true, EpdFontFamily::BOLD);
+    int y = pageHeight / 2 - 40;
+    renderer.drawCenteredText(UI_10_FONT_ID, y, tr(STR_TIME_SYNCED), true, EpdFontFamily::BOLD);
 
     time_t now = HalClock::now();
     struct tm timeinfo;
@@ -86,7 +132,45 @@ void SyncTimeActivity::render(RenderLock&&) {
     char timeStr[32];
     snprintf(timeStr, sizeof(timeStr), "%s  %04d-%02d-%02d", timePart, timeinfo.tm_year + 1900, timeinfo.tm_mon + 1,
              timeinfo.tm_mday);
-    renderer.drawCenteredText(UI_10_FONT_ID, pageHeight / 2 + 10, timeStr);
+    y += 30;
+    renderer.drawCenteredText(UI_10_FONT_ID, y, timeStr);
+
+    int32_t elapsedSinceSync = -1;
+    if (prevSyncTime > 0) {
+      elapsedSinceSync = (int32_t)(now - prevSyncTime);
+    }
+
+    char driftStr[80];
+    if (hadTimeBeforeSync) {
+      char driftFmt[24];
+      formatDuration(driftFmt, sizeof(driftFmt), driftSeconds);
+
+      if (elapsedSinceSync > 0) {
+        double hours = (double)elapsedSinceSync / 3600.0;
+        double rate = (double)driftSeconds / hours;
+        char rateFmt[16];
+        snprintf(rateFmt, sizeof(rateFmt), "%+.2f", rate);
+
+        char driftWithRate[48];
+        snprintf(driftWithRate, sizeof(driftWithRate), "%s (%s s/hr)", driftFmt, rateFmt);
+        snprintf(driftStr, sizeof(driftStr), tr(STR_CLOCK_DRIFT), driftWithRate);
+      } else {
+        snprintf(driftStr, sizeof(driftStr), tr(STR_CLOCK_DRIFT), driftFmt);
+      }
+    } else {
+      snprintf(driftStr, sizeof(driftStr), tr(STR_CLOCK_DRIFT), "N/A");
+    }
+    y += 30;
+    renderer.drawCenteredText(UI_10_FONT_ID, y, driftStr);
+
+    if (elapsedSinceSync > 0) {
+      char elapsedFmt[24];
+      formatElapsed(elapsedFmt, sizeof(elapsedFmt), elapsedSinceSync);
+      char lastSyncStr[48];
+      snprintf(lastSyncStr, sizeof(lastSyncStr), tr(STR_LAST_NTP_SYNC), elapsedFmt);
+      y += 25;
+      renderer.drawCenteredText(UI_10_FONT_ID, y, lastSyncStr);
+    }
 
     const auto labels = mappedInput.mapLabels(tr(STR_BACK), "", "", "");
     GUI.drawButtonHints(renderer, labels.btn1, labels.btn2, labels.btn3, labels.btn4);

src/activities/settings/SyncTimeActivity.h

@@ -15,6 +15,10 @@ class SyncTimeActivity final : public Activity {
  private:
   enum State { CONNECTING, SYNCING, SUCCESS, FAILED };
   State state = CONNECTING;
+  time_t preSyncTime = 0;
+  time_t prevSyncTime = 0;
+  int32_t driftSeconds = 0;
+  bool hadTimeBeforeSync = false;
   void onWifiSelectionComplete(bool success);
   void onWifiSelectionCancelled();
   void performSync();