Add a warning color when battery is low

The threshold is controlled via BatteryWarnThreshold and the color via
battery-warning

css/style.scss

@@ -231,7 +231,11 @@ highlight {
 }
 
 .battery-charging {
-    color: $orange
+    color: $orange;
+}
+
+.battery-warning {
+    color: $red;
 }
 
 .network-data-text {

data/config

@@ -39,6 +39,9 @@ ExitCommand: killall Hyprland
 # The folder, where the battery sensors reside
 BatteryFolder: /sys/class/power_supply/BAT1
 
+# Threshold, when the battery is considered low and a different color (as specified by the 'battery-warning' CSS property) is applied
+BatteryWarnThreshold: 20
+
 # The partition to monitor with disk sensor
 DiskPartition: /
 

src/Bar.cpp

@@ -107,6 +107,20 @@ namespace Bar
                     batteryText->RemoveClass("battery-charging");
                 wasCharging = false;
             }
+
+            // Add warning if color falls below threshold
+            if (!isCharging && percentage * 100 <= Config::Get().batteryWarnThreshold)
+            {
+                sensor.AddClass("battery-warning");
+                if (batteryText)
+                    batteryText->AddClass("battery-warning");
+            }
+            else
+            {
+                sensor.RemoveClass("battery-warning");
+                if (batteryText)
+                    batteryText->RemoveClass("battery-warning");
+            }
             return TimerResult::Ok;
         }
 
@@ -417,8 +431,7 @@ namespace Bar
 #endif
     }
 
-    void WidgetSensor(Widget& parent, TimerCallback<Sensor>&& callback, const std::string& sensorName, Text*& textPtr,
-                      Side side)
+    void WidgetSensor(Widget& parent, TimerCallback<Sensor>&& callback, const std::string& sensorName, Text*& textPtr, Side side)
     {
         auto eventBox = Widget::Create<EventBox>();
         Utils::SetTransform(*eventBox, {-1, false, SideToAlignment(side)});
@@ -571,12 +584,8 @@ namespace Bar
             box->AddClass("widget");
             switch (type)
             {
-            case AudioType::Input:
-                box->AddClass("mic");
-                break;
-            case AudioType::Output:
-                box->AddClass("audio");
-                break;
+            case AudioType::Input: box->AddClass("mic"); break;
+            case AudioType::Output: box->AddClass("audio"); break;
             }
 
             Utils::SetTransform(*box, {-1, false, SideToAlignment(side)});

src/Config.cpp

@@ -294,6 +294,7 @@ void Config::Load(const std::string& overrideConfigLocation)
         AddConfigVar("AudioScrollSpeed", config.audioScrollSpeed, lineView, foundProperty);
         AddConfigVar("SensorSize", config.sensorSize, lineView, foundProperty);
         AddConfigVar("NetworkIconSize", config.networkIconSize, lineView, foundProperty);
+        AddConfigVar("BatteryWarnThreshold", config.batteryWarnThreshold, lineView, foundProperty);
 
         AddConfigVar("AudioMinVolume", config.audioMinVolume, lineView, foundProperty);
         AddConfigVar("AudioMaxVolume", config.audioMaxVolume, lineView, foundProperty);

src/Config.h

@@ -78,6 +78,7 @@ public:
     uint32_t numWorkspaces = 9;            // How many workspaces to display
     uint32_t sensorSize = 24;              // The size of the circular sensors
     uint32_t networkIconSize = 24;         // The size of the two network arrows
+    uint32_t batteryWarnThreshold = 20;    // Threshold for color change when on battery
 
     char location = 'T'; // The Location of the bar. Can be L,R,T,B