package logx

import (
	"context"
	"log/slog"
	"time"

	"git.yuntuo.hk/k2safe/go-omni/internal/configdiag"
)

func logLocation(name string) (*time.Location, error) {
	if name == "" {
		return nil, nil
	}
	location, err := time.LoadLocation(name)
	if err != nil {
		return nil, configdiag.Wrap("timeZone", "must be an available IANA time zone or UTC", err)
	}
	return location, nil
}

// Convert only the record timestamp. User time.Time attributes retain their
// original locations; child loggers inherit this instance's location.
type zoneHandler struct {
	slog.Handler
	location *time.Location
}

func (h zoneHandler) Handle(ctx context.Context, r slog.Record) error {
	if !r.Time.IsZero() {
		r.Time = r.Time.In(h.location)
	}
	return h.Handler.Handle(ctx, r)
}
func (h zoneHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
	return zoneHandler{h.Handler.WithAttrs(attrs), h.location}
}
func (h zoneHandler) WithGroup(name string) slog.Handler {
	return zoneHandler{h.Handler.WithGroup(name), h.location}
}