package main

import (
	"bytes"
	"encoding/json"
	"flag"
	"fmt"
	"github.com/oz123/gupta"
	"log"
	"os"
	"time"
)

func readProcStatLine(r *os.File) string {
	buf := make([]byte, 80)
	r.ReadAt(buf, 0)
	idx := bytes.Index(buf, []byte("cpu0"))
	line := string(buf[:idx])
	r.Seek(0, 0)
	return line
}

func main() {
	var freq int
	var partition, netInterface string
	var load, memory, cpu bool

	flag.IntVar(&freq, "frequency", 5, "Frequency of polling in secods")
	flag.IntVar(&freq, "f", 5, "Frequency of polling in secods")
	flag.BoolVar(&memory, "m", false, "Poll memory")
	flag.BoolVar(&load, "l", false, "Poll load")
	flag.BoolVar(&cpu, "c", false, "poll CPU usage")
	flag.StringVar(&partition, "p", "", "Poll disk usage (partition)")
	flag.StringVar(&netInterface, "n", "", "Network usage (interface)")

	flag.Parse()

	fmt.Println(gupta.Hello())
	r, _ := os.Open("/proc/stat")
	m, _ := os.Open("/proc/meminfo")

	for true {
		line := readProcStatLine(r)
		time.Sleep(time.Second)
		lineNew := readProcStatLine(r)
		cpustat := gupta.NewCPUStat(line, lineNew)
		fmt.Printf("CPU usage %.2f%%\n", cpustat.CPUUsage())
		mem := gupta.NewMemory(m)
		//fmt.Printf("Memory free %d\n", mem.Total())
		report := gupta.GuptaReport{}
		report.MemoryUsage = mem
		writer := os.Stdout
		enc := json.NewEncoder(writer)
		if err := enc.Encode(&report); err != nil {
			log.Println(err)
		}
		m.Seek(0, 0)
	}
}