package logger

import (
	"io"
	"log/slog"
	"os"
	"strings"
)

func Init() {
	levelStr := strings.ToLower(os.Getenv("LOG_LEVEL"))
	var level slog.Level
	switch levelStr {
	case "debug":
		level = slog.LevelDebug
	case "warn":
		level = slog.LevelWarn
	case "error":
		level = slog.LevelError
	default:
		level = slog.LevelInfo
	}

	file, err := os.OpenFile("app.log", os.O_APPEND|os.O_CREATE|os.O_RDWR, 0666)
	var writer io.Writer = os.Stdout
	if err != nil {
		slog.Error("Error to create log file", "err", err)
	} else {
		writer = io.MultiWriter(os.Stdout, file)
	}

	opts := &slog.HandlerOptions{
		Level:     level,
		AddSource: true,
		ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
			if a.Key == slog.TimeKey {
				return slog.String(a.Key, a.Value.Time().Format("2006-01-02 15:04:05"))
			}
			return a
		},
	}

	handler := slog.NewJSONHandler(writer, opts)

	logger := slog.New(handler)
	slog.SetDefault(logger)
}