package logger

import (
	"fmt"
	"log/slog"
	"os"
	"strings"

	"codespace/pkg/config"
)

// New creates a *slog.Logger from the given log configuration.
// It also sets the logger as the default slog logger.
func New(cfg config.LogConfig) (*slog.Logger, error) {
	level, err := parseLevel(cfg.Level)
	if err != nil {
		return nil, err
	}

	opts := &slog.HandlerOptions{Level: level}
	var handler slog.Handler
	switch strings.ToLower(cfg.Format) {
	case "json", "":
		handler = slog.NewJSONHandler(os.Stdout, opts)
	case "text":
		handler = slog.NewTextHandler(os.Stdout, opts)
	default:
		return nil, fmt.Errorf("invalid log format %q", cfg.Format)
	}

	lg := slog.New(handler)
	slog.SetDefault(lg)
	return lg, nil
}

func parseLevel(value string) (slog.Level, error) {
	switch strings.ToLower(value) {
	case "debug":
		return slog.LevelDebug, nil
	case "info", "":
		return slog.LevelInfo, nil
	case "warn":
		return slog.LevelWarn, nil
	case "error":
		return slog.LevelError, nil
	default:
		return slog.LevelInfo, fmt.Errorf("invalid log level %q", value)
	}
}