Enhance display of BatteryMeter with extra information

Author: BenBE

BatteryMeter.c

@@ -43,21 +43,124 @@ static void BatteryMeter_updateValues(Meter* this) {
 
    this->values[0] = info.percent;
 
-   const char* text;
-   switch (info.ac) {
-      case AC_PRESENT:
-         text = this->mode == TEXT_METERMODE ? " (Running on A/C)" : "(A/C)";
-         break;
-      case AC_ABSENT:
-         text = this->mode == TEXT_METERMODE ? " (Running on battery)" : "(bat)";
-         break;
-      case AC_ERROR:
-      default:
-         text = "";
-         break;
+   bool haveEnergy = isNonnegative(info.energyCurr) && isNonnegative(info.energyFull);
+
+   /* Without energy data there is nothing useful to show beyond the percent. */
+   if (!haveEnergy) {
+      xSnprintf(this->txtBuffer, sizeof(this->txtBuffer), "%.1f%%", info.percent);
+      return;
+   }
+
+   bool havePower = isfinite(info.powerCurr);
+
+   /* stable: power unknown or |power| < 5 W – time estimate would be unreliable */
+   bool isDischarging = havePower && info.powerCurr <= -5.0;
+   bool isCharging = havePower && info.powerCurr >= 5.0;
+
+   /* time estimate in whole minutes; -1 means not available */
+   int timeMinutes = -1;
+   if (isDischarging && isPositive(info.energyCurr)) {
+      /* floor for discharge; powerCurr is negative, use negative scaling when dividing */
+      timeMinutes = (int)floor(info.energyCurr / info.powerCurr * -60.0);
+   } else if (isCharging && 0.95 * info.energyFull > info.energyCurr) {
+      /* ceil for charge */
+      timeMinutes = (int)ceil((0.95 * info.energyFull - info.energyCurr) / info.powerCurr * 60.0);
+   }
+
+   char* buf = this->txtBuffer;
+   size_t len = sizeof(this->txtBuffer);
+   int ret = 0;
+
+   if (this->mode == TEXT_METERMODE) {
+      if (info.ac == AC_PRESENT) {
+         ret = xSnprintf(buf, len, "Using %s", isDischarging ? "AC+bat" : "AC");
+         buf += ret; len -= ret;
+      } else if (info.ac == AC_ABSENT) {
+         ret = xSnprintf(buf, len, "Using bat");
+         buf += ret; len -= ret;
+      }
+
+      if (ret && len > 2) {
+         *buf++ = ',';
+         *buf++ = ' ';
+         *buf = 0;
+         len -= 2;
+      }
+
+      if (isDischarging) {
+         ret = xSnprintf(
+            buf, len, "discharging at %.1fW, %.1f/%.1fWh (%.1f%%)",
+            -info.powerCurr, info.energyCurr, info.energyFull, info.percent
+         );
+         buf += ret; len -= ret;
+         if (timeMinutes >= 0) {
+            ret = xSnprintf(buf, len, ", time remaining: %dh%02dm", timeMinutes / 60, timeMinutes % 60);
+            buf += ret; len -= ret;
+         }
+      } else if (isCharging) {
+         ret = xSnprintf(
+            buf, len, "charging at %.1fW, %.1f/%.1fWh (%.1f%%)",
+            info.powerCurr, info.energyCurr, info.energyFull, info.percent
+         );
+         buf += ret; len -= ret;
+
+         if (timeMinutes >= 0) {
+            ret = xSnprintf(
+               buf, len, ", time to full: %dh%02dm",
+               timeMinutes / 60, timeMinutes % 60
+            );
+            buf += ret; len -= ret;
+         }
+      } else {
+         ret = xSnprintf(
+            buf, len, "stable at %.1f/%.1fWh (%.1f%%)",
+            info.energyCurr, info.energyFull, info.percent
+         );
+         buf += ret; len -= ret;
+      }
+   } else {
+      /* compact label for bar / graph modes */
+      if (info.ac == AC_PRESENT) {
+         ret = xSnprintf(buf, len, "%s", isDischarging ? "AC+bat" : "AC");
+         buf += ret; len -= ret;
+      } else if (info.ac == AC_ABSENT) {
+         ret = xSnprintf(buf, len, "bat");
+         buf += ret; len -= ret;
+      }
+
+      if (ret && len > 1) {
+         *buf++ = ' ';
+         *buf = 0;
+         len--;
+      }
+
+      if (isCharging || isDischarging) {
+         ret = xSnprintf(
+            buf, len, "%+.1fW @ %.1f/%.1fWh",
+            info.powerCurr, info.energyCurr, info.energyFull
+         );
+         buf += ret; len -= ret;
+
+         if (timeMinutes >= 0) {
+            ret = xSnprintf(
+               buf, len, ", %dh%02dm",
+               timeMinutes / 60, timeMinutes % 60
+            );
+            buf += ret; len -= ret;
+         }
+      } else {
+         ret = xSnprintf(
+            buf, len, "stable @ %.1f/%.1fWh",
+            info.energyCurr, info.energyFull
+         );
+         buf += ret; len -= ret;
+      }
    }
 
-   xSnprintf(this->txtBuffer, sizeof(this->txtBuffer), "%.1f%%%s", info.percent, text);
+   // Simplify the pattern to always use "buf += ret; len -= ret;" for all cases
+   (void)ret;
+   (void)buf;
+   (void)len;
 }
 
 const MeterClass BatteryMeter_class = {