package stat

import (
	"io"
	"bufio"
	"strings"
)

type CPUStat struct {
	device,
	user,
	nice,
	system,
	idle,
	iowait,
	irq,
	softIrq,
	steal, // (over 2.6.11)
	guest, // (over 2.6.24)
	guestNice string //(over 2.6.33)
}

func (cpu CPUStat) Command() string {
	return "cat /proc/stat"
}

func (cpu CPUStat) Parse(r io.Reader) ([]CPUStat, error) {
	var (
		CPUStats = []CPUStat{}
		scanner  = bufio.NewScanner(r)
	)

	for scanner.Scan() {
		line := scanner.Text()
		parts := strings.Fields(line)
		if !strings.HasPrefix(parts[0], "cpu") {
			continue
		}

		steal, guest, guestNice := "", "", ""
		if len(parts) > 8 {
			steal = parts[8]
		}
		if len(parts) > 9 {
			guest = parts[9]
		}
		if len(parts) > 10 {
			guestNice = parts[10]
		}

		CPUStats = append(CPUStats, CPUStat{
			device:    parts[0],
			user:      parts[1],
			nice:      parts[2],
			system:    parts[3],
			idle:      parts[4],
			iowait:    parts[5],
			irq:       parts[6],
			softIrq:   parts[7],
			steal:     steal,
			guest:     guest,
			guestNice: guestNice,
		})
	}

	return CPUStats, scanner.Err()
}