package core

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

// NewLogger builds a structured logger from the configured level and format.
// Unknown values fall back rather than failing: a bad log level must never
// stop the server from booting.
func NewLogger(level, format string) *slog.Logger {
	var lvl slog.Level
	switch strings.ToLower(level) {
	case "debug":
		lvl = slog.LevelDebug
	case "warn", "warning":
		lvl = slog.LevelWarn
	case "error":
		lvl = slog.LevelError
	default:
		lvl = slog.LevelInfo
	}

	opts := &slog.HandlerOptions{Level: lvl}

	var h slog.Handler
	if strings.EqualFold(format, "json") {
		h = slog.NewJSONHandler(os.Stdout, opts)
	} else {
		h = slog.NewTextHandler(os.Stdout, opts)
	}
	return slog.New(h)
}