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
}