package system

import (
	"fmt"
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/rs/zerolog"
	"github.com/rs/zerolog/log"
	"github.com/spf13/viper"
	"kumoly.io/kumoly/app/util"
)

func init() {
	Home, err := os.UserHomeDir()
	if err != nil {
		Home = "/"
	}

	// Setup defaults
	// =========================================================
	// App
	viper.SetDefault("name", "app")
	viper.SetDefault("domain", "kumoly.io")
	viper.SetDefault("timezone", "Asia/Taipei")
	// mode [prod, dev]
	viper.SetDefault("prod", true)

	// log.level : [-1(trace):5(panic)] 7 to disable
	viper.SetDefault("log.level", int(zerolog.InfoLevel))
	viper.SetDefault("log.pretty", false)

	// data: data dir
	viper.SetDefault("data", filepath.Join(Home, ".kumoly"))

	// =========================================================
	// viper settings
	viper.SetEnvPrefix("app")
	replacer := strings.NewReplacer(".", "_")
	viper.SetEnvKeyReplacer(replacer)
	viper.AutomaticEnv()
	viper.SetConfigType("json")
	Setup()
}

func Setup() {
	zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
	zerolog.DurationFieldInteger = true
	zerolog.SetGlobalLevel(zerolog.Level(viper.GetInt("log.level")))
	util.PROD = viper.GetBool("prod")
	if !util.PROD {
		log.Logger = log.With().Caller().Logger()
	}
	if viper.GetBool("log.pretty") {
		log.Logger = log.Output(zerolog.ConsoleWriter{
			Out:        os.Stdout,
			TimeFormat: "2006/01/02 15:04:05",
			FormatCaller: func(i interface{}) string {
				var c string
				if cc, ok := i.(string); ok {
					c = cc
				}
				if len(c) > 0 {
					// shorten caller to mod/file:line
					segs := strings.Split(c, ":")
					file := segs[len(segs)-2]
					short := file
					ptr := 0
					for i := len(file) - 1; i > 0; i-- {
						if file[i] == '/' {
							if ptr == 0 {
								short = file[i+1:]
								ptr = i
							} else {
								short = fmt.Sprintf("%v/%v", file[i+1:ptr], short)
								break
							}
						}
						if file[i] == '@' {
							ptr = i
						}
					}
					return fmt.Sprintf("%v:%v", short, segs[len(segs)-1])
				}
				return c
			},
		})
	}
	l = log.With().Str("mod", "system").Logger()

	tz, err := time.LoadLocation(viper.GetString("timezone"))
	if err == nil {
		time.Local = tz
	} else {
		l.Error().Err(err).Msg("setup error")
	}
}

func SetConfigPath(path string) {
	ConfigRead(path)
}

func SetDataPath(path string) {
	viper.Set("data", path)
}

// ConfigRead read in config
func ConfigRead(cfgFile string) {
	if cfgFile != "" {
		viper.SetConfigFile(cfgFile)
	} else {
		// read config from default path
		viper.SetConfigName("app")
		viper.AddConfigPath(viper.GetString("data"))
	}
	if err := viper.ReadInConfig(); err != nil {
		l.Error().Err(err).Msg("ReadInConfig error")
	}
	Setup()
}

// ConfigWrite write current config to file
func ConfigWrite(file string) {
	viper.WriteConfigAs(file)
}

// ConfigShow print config to stdout
func ConfigShow(format string) (string, error) {
	if format == "" {
		format = "json"
	}
	path := filepath.Join(viper.GetString("data"), "tmp")
	util.Mkdir(path)
	file := filepath.Join(path, "config."+format)
	err := viper.WriteConfigAs(file)
	if err != nil {
		l.Error().Err(err).Msg("WriteConfigAs error")
		return "", err
	}
	data, err := ioutil.ReadFile(file)
	if err != nil {
		l.Error().Err(err).Msg("ReadFile error")
		return "", err
	}
	return string(data), nil
}