feat: implement the battery diectly instead of depency

agent/battery/battery_darwin.go

@@ -0,0 +1,114 @@
+//go:build darwin
+
+package battery
+
+import (
+	"errors"
+	"log/slog"
+	"math"
+	"os/exec"
+
+	"howett.net/plist"
+)
+
+const (
+	stateUnknown     uint8 = 0
+	stateEmpty       uint8 = 1
+	stateFull        uint8 = 2
+	stateCharging    uint8 = 3
+	stateDischarging uint8 = 4
+	stateIdle        uint8 = 5
+)
+
+type macBattery struct {
+	CurrentCapacity   int  `plist:"CurrentCapacity"`
+	MaxCapacity       int  `plist:"MaxCapacity"`
+	FullyCharged      bool `plist:"FullyCharged"`
+	IsCharging        bool `plist:"IsCharging"`
+	ExternalConnected bool `plist:"ExternalConnected"`
+}
+
+var (
+	systemHasBattery   = false
+	haveCheckedBattery = false
+)
+
+func readMacBatteries() ([]macBattery, error) {
+	out, err := exec.Command("ioreg", "-n", "AppleSmartBattery", "-r", "-a").Output()
+	if err != nil {
+		return nil, err
+	}
+	if len(out) == 0 {
+		return nil, nil
+	}
+	var batteries []macBattery
+	if _, err := plist.Unmarshal(out, &batteries); err != nil {
+		return nil, err
+	}
+	return batteries, nil
+}
+
+// HasReadableBattery checks if the system has a battery and returns true if it does.
+func HasReadableBattery() bool {
+	if haveCheckedBattery {
+		return systemHasBattery
+	}
+	haveCheckedBattery = true
+	batteries, err := readMacBatteries()
+	for _, bat := range batteries {
+		if bat.MaxCapacity > 0 {
+			systemHasBattery = true
+			break
+		}
+	}
+	if !systemHasBattery {
+		slog.Debug("No battery found", "err", err)
+	}
+	return systemHasBattery
+}
+
+// GetBatteryStats returns the current battery percent and charge state.
+// Uses CurrentCapacity/MaxCapacity to match the value macOS displays.
+func GetBatteryStats() (batteryPercent uint8, batteryState uint8, err error) {
+	if !HasReadableBattery() {
+		return batteryPercent, batteryState, errors.ErrUnsupported
+	}
+	batteries, err := readMacBatteries()
+	if len(batteries) == 0 {
+		return batteryPercent, batteryState, errors.New("no batteries")
+	}
+
+	totalCapacity := 0
+	totalCharge := 0
+	batteryState = math.MaxUint8
+
+	for _, bat := range batteries {
+		if bat.MaxCapacity == 0 {
+			// skip ghost batteries with 0 capacity
+			// https://github.com/distatus/battery/issues/34
+			continue
+		}
+		totalCapacity += bat.MaxCapacity
+		totalCharge += min(bat.CurrentCapacity, bat.MaxCapacity)
+
+		switch {
+		case !bat.ExternalConnected:
+			batteryState = stateDischarging
+		case bat.IsCharging:
+			batteryState = stateCharging
+		case bat.CurrentCapacity == 0:
+			batteryState = stateEmpty
+		case !bat.FullyCharged:
+			batteryState = stateIdle
+		default:
+			batteryState = stateFull
+		}
+	}
+
+	if totalCapacity == 0 || batteryState == math.MaxUint8 {
+		return batteryPercent, batteryState, errors.New("no battery capacity")
+	}
+
+	batteryPercent = uint8(float64(totalCharge) / float64(totalCapacity) * 100)
+	return batteryPercent, batteryState, nil
+}