Add battery info

internal/collectors/battery.go

@@ -1 +1,62 @@
 package collectors
+
+import (
+	"bufio"
+	"log"
+	"os"
+	"strconv"
+)
+
+func batteryCapacity() (capacity int) {
+	const filename string = "/sys/class/power_supply/BAT0/capacity"
+	var rawCapacity string
+
+	file, err := os.Open(filename)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+
+	if scanner.Scan() {
+		rawCapacity = scanner.Text()
+	}
+
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+	capacity, err = strconv.Atoi(rawCapacity)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return capacity
+}
+
+func batteryStatus() (status string) {
+	const filename string = "/sys/class/power_supply/BAT0/status"
+
+	file, err := os.Open(filename)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+
+	if scanner.Scan() {
+		status = scanner.Text()
+	}
+
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+	return status
+}
+
+func batteryInfo() (capacity int, status string) {
+	const statusFile string = "/sys/class/power_supply/BAT0/status"
+	capacity = batteryCapacity()
+	status = batteryStatus()
+	return capacity, status
+}

internal/collectors/collector.go

@@ -17,6 +17,7 @@ type StatusInfo struct {
 func Collect() (*StatusInfo, error) {
 	year, month, day, hour, minute, second := datetime()
 	cpuLoad1, cpuLoad5, cpuLoad15 := cpuLoad()
+	capacity, status := batteryInfo()
 	return &StatusInfo{
 		CPULoad1:       cpuLoad1,
 		CPULoad5:       cpuLoad5,
@@ -27,7 +28,7 @@ func Collect() (*StatusInfo, error) {
 		Hour:           hour,
 		Minute:         minute,
 		Second:         second,
-		BatteryPercent: 100,
-		BatteryStatus:  "Charging",
+		BatteryPercent: capacity,
+		BatteryStatus:  status,
 	}, nil
 }

internal/output/stdout.go

@@ -7,7 +7,9 @@ import (
 
 func Print(c *collectors.StatusInfo) {
 	fmt.Printf(
-		"LOAD: %.2f %.2f %.2f | %d-%02d-%02d %02d:%02d\n",
+		"BAT: %d%% (%s) | LOAD: %.2f %.2f %.2f | %d-%02d-%02d %02d:%02d\n",
+		c.BatteryPercent,
+		c.BatteryStatus,
 		c.CPULoad1,
 		c.CPULoad5,
 		c.CPULoad15,