package main

import (
	"bufio"
	"fmt"
	"os"
	"runtime"
	"strings"
	"time"

	"github.com/shirou/gopsutil/v3/cpu"
	"github.com/shirou/gopsutil/v3/mem"
)

func linuxID() string {
	f, err := os.Open("/etc/os-release")
	if err != nil {
		return ""
	}
	defer f.Close()
	sc := bufio.NewScanner(f)
	for sc.Scan() {
		line := sc.Text()
		if strings.HasPrefix(line, "ID=") {
			val := strings.TrimPrefix(line, "ID=")
			val = strings.Trim(val, `"`)
			return strings.ToLower(val)
		}
	}
	return ""
}

func isSupported() bool {
	switch runtime.GOOS {
	case "darwin":
		return true
	case "linux":
		id := linuxID()
		return id == "ubuntu" || id == "arch"
	default:
		return false
	}
}

func main() {
	if !isSupported() {
		return
	}
	values, err := cpu.Percent(400*time.Millisecond, false)
	if err != nil || len(values) == 0 {
		return
	}
	vm, err := mem.VirtualMemory()
	if err != nil {
		return
	}
	fmt.Printf("CPU %.0f%% | RAM %.0f%%", values[0], vm.UsedPercent)
}