package gotop

import (
	"bufio"
	"fmt"
	"io"
	"strconv"
	"strings"
	"time"

	"github.com/xxxserxxx/gotop/v3/colorschemes"
	"github.com/xxxserxxx/gotop/v3/widgets"
)

// TODO: test, build, release [#119] [#120] [#121]
type Config struct {
	ConfigDir string
	LogDir    string
	LogFile   string

	GraphHorizontalScale int
	HelpVisible          bool
	Colorscheme          colorschemes.Colorscheme

	UpdateInterval time.Duration
	AverageLoad    bool
	PercpuLoad     bool
	Statusbar      bool
	TempScale      widgets.TempScale
	NetInterface   string
	Layout         string
	MaxLogSize     int64
	ExportPort     string
	Extensions     []string
}

func Parse(in io.Reader, conf *Config) error {
	r := bufio.NewScanner(in)
	var lineNo int
	for r.Scan() {
		l := strings.TrimSpace(r.Text())
		kv := strings.Split(l, "=")
		if len(kv) != 2 {
			return fmt.Errorf("bad config file syntax; should be KEY=VALUE, was %s", l)
		}
		key := strings.ToLower(kv[0])
		switch key {
		default:
			return fmt.Errorf("invalid config option %s", key)
		case "configdir":
			conf.ConfigDir = kv[1]
		case "logdir":
			conf.LogDir = kv[1]
		case "logfile":
			conf.LogFile = kv[1]
		case "graphhorizontalscale":
			iv, err := strconv.Atoi(kv[1])
			if err != nil {
				return err
			}
			conf.GraphHorizontalScale = iv
		case "helpvisible":
			bv, err := strconv.ParseBool(kv[1])
			if err != nil {
				return fmt.Errorf("line %d: %v", lineNo, err)
			}
			conf.HelpVisible = bv
		case "colorscheme":
			cs, err := colorschemes.FromName(conf.ConfigDir, kv[1])
			if err != nil {
				return fmt.Errorf("line %d: %v", lineNo, err)
			}
			conf.Colorscheme = cs
		case "updateinterval":
			iv, err := strconv.Atoi(kv[1])
			if err != nil {
				return err
			}
			conf.UpdateInterval = time.Duration(iv)
		case "averagecpu":
			bv, err := strconv.ParseBool(kv[1])
			if err != nil {
				return fmt.Errorf("line %d: %v", lineNo, err)
			}
			conf.AverageLoad = bv
		case "percpuload":
			bv, err := strconv.ParseBool(kv[1])
			if err != nil {
				return fmt.Errorf("line %d: %v", lineNo, err)
			}
			conf.PercpuLoad = bv
		case "tempscale":
			iv, err := strconv.Atoi(kv[1])
			if err != nil {
				return err
			}
			conf.TempScale = widgets.TempScale(iv)
		case "statusbar":
			bv, err := strconv.ParseBool(kv[1])
			if err != nil {
				return fmt.Errorf("line %d: %v", lineNo, err)
			}
			conf.Statusbar = bv
		case "netinterface":
			conf.NetInterface = kv[1]
		case "layout":
			conf.Layout = kv[1]
		case "maxlogsize":
			iv, err := strconv.Atoi(kv[1])
			if err != nil {
				return err
			}
			conf.MaxLogSize = int64(iv)
		case "export":
			conf.ExportPort = kv[1]
		case "extensions":
			conf.Extensions = strings.Split(kv[1], ",")
		}
	}

	return nil
}