package reach

import (
	"sync"

	"forge.cadoles.com/Pyxis/golang-socketio"
	"github.com/pkg/errors"
)

const (
	eventUpdate           = "update"
	eventOPKGUpdateResult = "opkg update result"
)

// UpdateStatus embeds informations about update status
type UpdateStatus struct {
	Active bool   `json:"active"`
	Locked bool   `json:"locked"`
	State  string `json:"state"`
}

// Update asks the ReachRS module to start an OPKG update
func (u *Updater) Update() (*UpdateStatus, error) {

	var err error
	var status *UpdateStatus
	var wg sync.WaitGroup

	wg.Add(1)

	err = u.conn.On(eventOPKGUpdateResult, func(h *gosocketio.Channel, st *UpdateStatus) {
		status = st
		u.conn.Off(eventOPKGUpdateResult)
		wg.Done()
	})
	if err != nil {
		return nil, errors.Wrapf(err, "error while binding to '%s' event", eventOPKGUpdateResult)
	}

	u.logf("sending '%s' event", eventUpdate)
	if err = u.conn.Emit(eventUpdate, nil); err != nil {
		return nil, errors.Wrapf(err, "error while emitting '%s' event", eventUpdate)
	}
	u.logf("'%s' event sent", eventUpdate)

	wg.Wait()

	u.logf(
		"opkg update result: active: %v, state: %v, locked: %v",
		status.Active, status.State, status.Locked,
	)

	return status, err

}