package data

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

type AppLogHandler struct {
	level   slog.Level
	logFunc func(string, ...any)
	attrs   []slog.Attr
	groups  []string
}

func NewAppLogHandler(f func(string, ...any)) *AppLogHandler {
	return &AppLogHandler{logFunc: f}
}

func (a *AppLogHandler) SetLevel(l slog.Level)       { a.level = l }
func (a *AppLogHandler) setAttrs(attrs ...slog.Attr) { a.attrs = attrs }
func (a *AppLogHandler) addAttrs(attrs ...slog.Attr) { a.attrs = append(a.attrs, attrs...) }
func (a *AppLogHandler) setGroups(groups ...string)  { a.groups = groups }
func (a *AppLogHandler) addGroups(groups ...string)  { a.groups = append(a.groups, groups...) }

// AppLogHandler can handle all levels
func (a *AppLogHandler) Enabled(_ context.Context, lvl slog.Level) bool { return lvl >= a.level }

func (a *AppLogHandler) Handle(ctx context.Context, rcd slog.Record) error {
	if a.logFunc == nil {
		return errors.New("no log func defined")
	}
	a.logFunc("%s %s %s", rcd.Time.Format(time.TimeOnly), rcd.Level, rcd.Message)
	return nil
}

func (a *AppLogHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
	attrs = append(attrs, a.attrs...)
	ret := NewAppLogHandler(a.logFunc)
	ret.addAttrs(attrs...)
	return ret
}

func (a *AppLogHandler) WithGroup(name string) slog.Handler {
	groups := append(a.groups, name)
	ret := NewAppLogHandler(a.logFunc)
	ret.setGroups(groups...)
	return ret
}