add FreeBSD support to power module

uses the FreeBSD apm command to get charge status
and battery percentage

Signed-off-by: Christopher Hall <hsw@ms2.hinet.net>

modules/power/battery.go

@@ -1,4 +1,5 @@
 // +build !linux
+// +build !freebsd
 
 package power
 

modules/power/battery_freebsd.go

@@ -0,0 +1,106 @@
+// +build freebsd
+
+package power
+
+import (
+	"fmt"
+	"os/exec"
+	"strconv"
+	"strings"
+
+	"github.com/wtfutil/wtf/utils"
+)
+
+var batteryState string
+
+type Battery struct {
+	args   []string
+	cmd    string
+	result string
+
+	Charge    string
+	Remaining string
+}
+
+func NewBattery() *Battery {
+	return &Battery{}
+}
+
+/* -------------------- Exported Functions -------------------- */
+
+func (battery *Battery) Refresh() {
+	data := battery.execute()
+	battery.result = battery.parse(data)
+}
+
+func (battery *Battery) String() string {
+	return battery.result
+}
+
+/* -------------------- Unexported Functions -------------------- */
+
+// returns 3 numbers
+//   1/0   = AC/battery
+//   c     = battery charge percentage
+//   -1/s  = charging / seconds to empty
+func (battery *Battery) execute() string {
+	cmd := exec.Command("apm", "-alt")
+	return utils.ExecuteCommand(cmd)
+}
+
+func (battery *Battery) parse(data string) string {
+	lines := strings.Split(data, "\n")
+	if len(lines) < 3 {
+		return "unknown"
+	}
+	batteryState = strings.TrimSpace(lines[0])
+	charge := strings.TrimSpace(lines[1])
+	timeToEmpty := "∞"
+	seconds, err := strconv.Atoi(strings.TrimSpace(lines[2]))
+	if err == nil && seconds >= 0 {
+		h := seconds / 3600
+		m := seconds % 3600 / 60
+		s := seconds % 60
+		timeToEmpty = fmt.Sprintf("%2d:%02d:%02d", h, m, s)
+	}
+
+	str := fmt.Sprintf(" %10s: %s%%\n", "Charge", battery.formatCharge(charge))
+	str += fmt.Sprintf(" %10s: %s\n", "Remaining", timeToEmpty)
+	str += fmt.Sprintf(" %10s: %s\n", "State", battery.formatState(batteryState))
+	//	if s := table["time to full"]; s != "" {
+	//		str += fmt.Sprintf(" %10s: %s\n", "TimeToFull", table["time to full"])
+	//	}
+
+	return str
+}
+
+func (battery *Battery) formatCharge(data string) string {
+	percent, _ := strconv.ParseFloat(strings.Replace(data, "%", "", -1), 32)
+	color := ""
+
+	switch {
+	case percent >= 70:
+		color = "[green]"
+	case percent >= 35:
+		color = "[yellow]"
+	default:
+		color = "[red]"
+	}
+
+	return color + data + "[white]"
+}
+
+func (battery *Battery) formatState(data string) string {
+	color := ""
+
+	switch data {
+	case "1":
+		color = "[green]charging"
+	case "0":
+		color = "[yellow]discharging"
+	default:
+		color = "[white]unknown"
+	}
+
+	return color + "[white]"
+}

modules/power/source.go

@@ -1,4 +1,5 @@
 // +build !linux
+// +build !freebsd
 
 package power
 

modules/power/source_freebsd.go

@@ -0,0 +1,15 @@
+// +build freebsd
+
+package power
+
+// powerSource returns the name of the current power source, probably one of
+// "AC Power" or "Battery Power"
+func powerSource() string {
+	switch batteryState {
+	case "1":
+		return "AC Power"
+	case "0":
+		return "Battery Power"
+	}
+	return batteryState
+}