package logging

import (
	"encoding/json"
	"fmt"
	"io"
	"os"
	"time"

	"github.com/rs/zerolog"

	"www.thenautilus.net/cgit/go-example/config"
)

// Logger returns a (optionally verbose) logger.
func Logger(conf config.LoggerConfig) zerolog.Logger {
	logLevel := zerolog.InfoLevel
	if conf.Verbose {
		logLevel = zerolog.DebugLevel
	}

	zerolog.TimestampFunc = func() time.Time {
		return time.Now().UTC()
	}

	zerolog.InterfaceMarshalFunc = func(value interface{}) ([]byte, error) {
		switch v := value.(type) {
		case fmt.Stringer:
			str := fmt.Sprintf("\"%s\"", v.String())

			return []byte(str), nil
		default:
			return json.Marshal(value)
		}
	}

	var w io.Writer = os.Stdout
	if conf.Format == "console" {
		w = zerolog.NewConsoleWriter()
	}

	return zerolog.New(w).Level(logLevel).With().Timestamp().Logger()
}