Track the power profile through Quickshell instead of polling busctl (#15027)

* Track the power profile through Quickshell instead of polling busctl

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Recover the power profile when the daemon was down at shell start

Addresses Codex review: Quickshell never attaches its PowerProfiles listener if the daemon failed at startup. One-off reads on startup, power source changes and an IPC refresh from omarchy-powerprofiles-set cover that, still with no timer.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Don't let a stale power profile read win over a change signal or drop a refresh

Addresses Codex re-review: a busctl read in flight could overwrite a newer PowerProfiles signal, and refreshes requested while a read ran were dropped.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Test power profile transitions and stale reads as behavior, not source text

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

bin/omarchy-powerprofiles-set

@@ -56,6 +56,7 @@ if [[ -z ${profile:-} ]] || ! profile_available "$profile"; then
 fi
 
 powerprofilesctl set "$profile" || exit
+omarchy-shell -q battery refreshPowerProfile >/dev/null 2>&1 || true
 
 if [[ -n $requested_profile ]]; then
   mkdir -p "$state_dir"

shell/plugins/services/battery/BatteryModel.js

@@ -19,10 +19,32 @@ function shouldWarnLowBattery(device, onBattery, dischargingState, threshold, al
   }
 }
 
+function parseActiveProfile(text) {
+  // busctl --json=short prints {"type":"s","data":"balanced"}; an empty or
+  // malformed reply (daemon not running) reads as no active profile.
+  try {
+    return String(JSON.parse(text).data || "").trim()
+  } catch (e) {
+    return ""
+  }
+}
+
+function profileAfterRead(current, replyText, signalsAtStart, signalsNow) {
+  // A change signal that arrived during the read is newer than its reply.
+  return signalsAtStart === signalsNow ? parseActiveProfile(replyText) : current
+}
+
+function isPowerSaverOnBattery(onBattery, profile) {
+  return !!onBattery && profile === "power-saver"
+}
+
 if (typeof module !== "undefined") {
   module.exports = {
     batteryPercentage: batteryPercentage,
     isDischarging: isDischarging,
-    shouldWarnLowBattery: shouldWarnLowBattery
+    shouldWarnLowBattery: shouldWarnLowBattery,
+    parseActiveProfile: parseActiveProfile,
+    profileAfterRead: profileAfterRead,
+    isPowerSaverOnBattery: isPowerSaverOnBattery
   }
 }

shell/plugins/services/battery/Service.qml

@@ -2,6 +2,7 @@ import QtQuick
 import Quickshell
 import Quickshell.Io
 import Quickshell.Services.UPower
+import qs.Commons
 import "BatteryModel.js" as BatteryModel
 
 Item {
@@ -12,8 +13,15 @@ Item {
 
   readonly property int batteryThreshold: 10
   property string pendingPowerSource: ""
+  // Follows power-profiles-daemon's change signals, so nothing polls it.
+  // Quickshell never attaches that listener if the daemon failed when the
+  // shell started, so a one-off read on startup, on a power source change and
+  // after omarchy-powerprofiles-set (which asks for it over IPC) recovers.
   property string activePowerProfile: ""
-  readonly property bool powerSaverOnBattery: UPower.onBattery && activePowerProfile === "power-saver"
+  property bool powerProfileReadPending: false
+  property int powerProfileSignals: 0
+  property int powerProfileReadSignals: 0
+  readonly property bool powerSaverOnBattery: BatteryModel.isPowerSaverOnBattery(UPower.onBattery, activePowerProfile)
 
   PersistentProperties {
     id: persisted
@@ -56,16 +64,22 @@ Item {
   }
 
   function refreshPowerProfile() {
-    if (!powerProfileReadProcess.running) powerProfileReadProcess.running = true
+    // A read already running may have sampled the profile before the change
+    // this refresh is for, so run another once it finishes.
+    if (powerProfileReadProcess.running) {
+      powerProfileReadPending = true
+      return
+    }
+    powerProfileReadPending = false
+    powerProfileReadSignals = powerProfileSignals
+    powerProfileReadProcess.running = true
   }
 
-  function parseActiveProfile(text) {
-    // busctl --json=short prints {"type":"s","data":"balanced"}; an empty or
-    // malformed reply (daemon not running) reads as no active profile.
-    try {
-      return String(JSON.parse(text).data || "").trim()
-    } catch (e) {
-      return ""
+  function profileName(profile) {
+    switch (profile) {
+      case PowerProfile.PowerSaver: return "power-saver"
+      case PowerProfile.Performance: return "performance"
+      default: return "balanced"
     }
   }
 
@@ -83,26 +97,32 @@ Item {
     id: powerProfileReadProcess
     // Read the property straight from the daemon rather than via
     // `powerprofilesctl get`. That is a PyGObject script, and spawning a Python
-    // interpreter for it every two seconds trips a CPython 3.14 shutdown race
+    // interpreter for it trips a CPython 3.14 shutdown race
     // (python/cpython#124619): the GLib D-Bus worker thread re-enters the
-    // interpreter after finalization and the process dies with SIGSEGV,
-    // leaving a core dump and a crash notification behind roughly daily.
+    // interpreter after finalization and the process dies with SIGSEGV.
     command: ["busctl", "--json=short", "get-property", "net.hadess.PowerProfiles", "/net/hadess/PowerProfiles", "net.hadess.PowerProfiles", "ActiveProfile"]
     stdout: StdioCollector {
       waitForEnd: true
-      onStreamFinished: root.activePowerProfile = root.parseActiveProfile(text)
+      onStreamFinished: root.activePowerProfile = BatteryModel.profileAfterRead(root.activePowerProfile, text, root.powerProfileReadSignals, root.powerProfileSignals)
+    }
+    onExited: {
+      // Deferred: the process still reports running while it signals exit.
+      if (root.powerProfileReadPending) Qt.callLater(root.refreshPowerProfile)
     }
   }
 
-  Timer {
-    // There is no portable way to subscribe to profile changes from QML; keep
-    // them visible to consumers such as the wallpaper service without requiring
-    // the power panel to be open.
-    interval: 2000
-    running: true
-    repeat: true
-    triggeredOnStart: true
-    onTriggered: root.refreshPowerProfile()
+  Connections {
+    target: PowerProfiles
+    function onProfileChanged() {
+      root.powerProfileSignals++
+      root.activePowerProfile = root.profileName(PowerProfiles.profile)
+    }
+  }
+
+  ShellIpc {
+    target: "battery"
+
+    function refreshPowerProfile(): void { root.refreshPowerProfile() }
   }
 
   Timer {

test/shell.d/battery-test.sh

@@ -28,4 +28,30 @@ assertDeepEqual(
   { level: 40, notify: false, notifiedLowBattery: false },
   'battery clears notified state after recovery'
 )
+
+const reply = profile => JSON.stringify({ type: 's', data: profile })
+assertEqual(battery.parseActiveProfile(reply('power-saver')), 'power-saver', 'battery parses the busctl profile reply')
+assertEqual(battery.parseActiveProfile(''), '', 'battery reads a missing daemon as no profile')
+
+// Walk the profile through a session on battery: a startup read, then change
+// signals, with the lock video gated on power-saver.
+let profile = battery.profileAfterRead('', reply('balanced'), 0, 0)
+assert(!battery.isPowerSaverOnBattery(true, profile), 'battery keeps the video on balanced')
+profile = 'power-saver'
+assert(battery.isPowerSaverOnBattery(true, profile), 'battery stops the video when power-saver arrives on battery')
+assert(!battery.isPowerSaverOnBattery(false, profile), 'battery ignores power-saver on AC')
+profile = 'balanced'
+assert(!battery.isPowerSaverOnBattery(true, profile), 'battery resumes the video when power-saver ends')
+
+// A read that sampled balanced before a power-saver signal must not undo it.
+const signalsAtStart = 3
+profile = 'power-saver'
+profile = battery.profileAfterRead(profile, reply('balanced'), signalsAtStart, signalsAtStart + 1)
+assertEqual(profile, 'power-saver', 'battery drops a read made stale by a change signal')
+assert(battery.isPowerSaverOnBattery(true, profile), 'battery keeps the video stopped after a stale read')
+assertEqual(
+  battery.profileAfterRead('balanced', reply('power-saver'), signalsAtStart, signalsAtStart),
+  'power-saver',
+  'battery takes a read no signal overtook'
+)
 JS

test/shell.d/video-background-test.sh

@@ -147,10 +147,17 @@ assert(
 )
 assert(
   batteryService.includes('property string activePowerProfile') &&
-    batteryService.includes('UPower.onBattery && activePowerProfile === "power-saver"') &&
+    batteryService.includes('powerSaverOnBattery: BatteryModel.isPowerSaverOnBattery(UPower.onBattery, activePowerProfile)') &&
+    /function onProfileChanged\(\) \{\s*root\.powerProfileSignals\+\+\s*root\.activePowerProfile = root\.profileName\(PowerProfiles\.profile\)/.test(batteryService) &&
+    batteryService.includes('root.activePowerProfile = BatteryModel.profileAfterRead(root.activePowerProfile, text, root.powerProfileReadSignals, root.powerProfileSignals)') &&
+    /if \(powerProfileReadProcess\.running\) \{\s*powerProfileReadPending = true/.test(batteryService) &&
+    batteryService.includes('if (root.powerProfileReadPending) Qt.callLater(root.refreshPowerProfile)') &&
+    batteryService.includes('case PowerProfile.PowerSaver: return "power-saver"') &&
     batteryService.includes('"get-property", "net.hadess.PowerProfiles", "/net/hadess/PowerProfiles", "net.hadess.PowerProfiles", "ActiveProfile"') &&
     !batteryService.includes('["powerprofilesctl"') &&
-    batteryService.includes('interval: 2000'),
+    !/Timer \{[^}]*refreshPowerProfile/.test(batteryService) &&
+    batteryService.includes('function refreshPowerProfile(): void { root.refreshPowerProfile() }') &&
+    fs.readFileSync(path.join(root, 'bin/omarchy-powerprofiles-set'), 'utf8').includes('omarchy-shell -q battery refreshPowerProfile'),
   'the battery service tracks the active power-saver profile'
 )
 assert(