package status // import "hhvn.uk/hbspbar/status"

import (
	"os"
	"io"
	"path"
	"strings"

	// "hhvn.uk/hbspbar/drw"
	"hhvn.uk/hbspbar/config"
	"hhvn.uk/hbspbar/common"
)

func read(file string) (string, error) {
		f, err := os.Open(file)
		if err != nil { return "", err }

		content, err := io.ReadAll(f)
		if err != nil { return "", err }

		str := strings.TrimSuffix(string(content), "\n")
		
		return str, nil
}

func init() {
	name := "bat"
	register(name)

	dir := "/sys/class/power_supply"

	const (
		nothing = iota
		charging
		discharging
	)

	go func(){
		for {
			u := newUpdate(name)

			dirs, _ := os.ReadDir(dir)
			if dirs == nil { return }

			totalcap := 0
			usedcap := 0

			stati := nothing

			for _, d := range dirs {
				if !strings.HasPrefix(d.Name(), "BAT") { continue }
				
				caps, err := read(path.Join(dir, d.Name(), "capacity"))
				if err != nil { return }

				capi, err := common.Intify(caps)
				if err != nil { return }

				totalcap += 100
				usedcap += capi

				stats, err := read(path.Join(dir, d.Name(), "status"))
				if err != nil { return }

				// Doesn't deal with 1 battery charging, and another discharging but w/e
				switch stats {
				case "Charging": if charging > stati { stati = charging }
				case "Discharging": if discharging > stati { stati = discharging}
				}
			}

			if totalcap == 0 { return }
			
			avgcap := (usedcap * 100) / totalcap

			var c uint32

			// Colour of outline = charge indicator
			switch stati {
			case nothing:     c = config.Fg
			case charging:    c = Green
			case discharging: c = Red
			}

			var iw int = 20
			var ih int = int(config.H) - 8
			var w  int = iw * avgcap / 100

			// Draw nose
			u.drawRect(2, int((config.H - 5) / 2), 2, 5, c, true)

			// Draw border
			u.drawRect(4, 3, iw + 2, ih + 2, c, false)

			switch {
			case avgcap < 25:  c = Red
			case avgcap >= 99: c = Green
			default:           c = config.FgDark
			}

			// Fill
			u.drawRect(4 + iw - w, 4, w + 1, ih, c, true)

			updates <- u
			sleep(1)
		}

	}()
}