package logging

import (
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"

	lib "git.sr.ht/~cco/go-scopes"
	"git.sr.ht/~cco/go-scopes/config"
	"github.com/rs/zerolog"
	"github.com/rs/zerolog/log"
)

const (
	DebugLevel = zerolog.DebugLevel
	InfoLevel  = zerolog.InfoLevel
	WarnLevel  = zerolog.WarnLevel
	ErrorLevel = zerolog.ErrorLevel
)

var Levels = map[string]zerolog.Level{
	"debug": DebugLevel,
	"info":  InfoLevel,
	"warn":  WarnLevel,
	"error": ErrorLevel,
}

type Logger = zerolog.Logger

var defaultLogger = log.Logger.Level(InfoLevel)
var globalLogger *Logger = &log.Logger

type Cfg struct {
	*config.BaseCfg
	Logfile string
	Level   string
}

func SetDefault() {
	logger := defaultLogger
	globalLogger = &logger
}

func Setup(ctx lib.Context, cfg *Cfg, home string) {
	if cfg == nil {
		return // use unchanged predefined logger
	}
	if logger, err := New(cfg, home); err != nil {
		panic("error when trying to set up logger.")
	} else {
		*globalLogger = *logger
	}
}

func New(cfg *Cfg, home string) (*Logger, error) {
	home, _ = filepath.Abs(home)
	fn := cfg.Logfile
	if fn == "" {
		fn = filepath.Join(home, "log", "scopes.log")
	} else if !filepath.IsAbs(fn) {
		fn = filepath.Join(home, fn)
	}
	f, err := os.OpenFile(fn, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0664)
	if err != nil {
		GetLogger(nil).Err(err).Msg("logging.New: open log file")
		return nil, err
	}
	//logger := zerolog.New(f).With().Timestamp().Caller().Logger()
	logger := zerolog.New(f).With().Timestamp().Logger()
	if cfg.Level != "" {
		if lvl, ok := Levels[cfg.Level]; ok {
			logger = logger.Level(lvl)
		} else {
			GetLogger(nil).Warn().Str("level", cfg.Level).
				Msg("logging.New: undefined level")
		}
	}
	return &logger, nil
}

func GetLogger(ctx lib.Context) *Logger {
	if ctx == nil {
		return globalLogger
	}
	// return ctx.Logger()
	return globalLogger
}

// processing and printing of log data

func Parse(rec string) map[string]interface{} {
	var buf map[string]interface{}
	if err := json.Unmarshal([]byte(rec), &buf); err != nil {
		fmt.Println("logging.Parse:", err)
	}
	return buf
}