package arlo

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	log "github.com/sirupsen/logrus"

	"github.com/go-resty/resty/v2"
)

type Arlo struct {
	client      *resty.Client
	eventStream *eventStream

	Account      Account
	Basestations []*Basestation
	Cameras      []*Camera
}

func NewArlo() (arlo *Arlo) {

	c := resty.New().
		SetHostURL(BaseUrl).
		SetTimeout(30 * time.Second)

	return &Arlo{
		client: c,
	}
}

func (a *Arlo) getBaseRequest(body interface{}, result interface{}, errResult interface{}, xcloudId string) *resty.Request {
	r := a.client.R().
		SetBody(body).
		SetResult(result).
		SetError(errResult)
	if xcloudId != "" {
		r.SetHeader("xcloudId", xcloudId)
	}
	return r
}

func (a *Arlo) get(url string, result interface{}) error {
	var errorResponse ErrorResponse
	resp, err := a.getBaseRequest(nil, result, &errorResponse, "").
		Get(url)
	if err != nil {
		return err
	}
	if resp.IsError() {
		return fmt.Errorf(errorResponse.Reason)
	}
	return nil
}

func (a *Arlo) post(url string, body interface{}, result interface{}, xcloudId string) error {
	var errorResponse ErrorResponse
	request := a.getBaseRequest(body, result, &errorResponse, xcloudId)
	resp, err := request.
		Post(url)
	if err != nil {
		return err
	}
	if resp.IsError() {
		return fmt.Errorf(errorResponse.Reason)
	}
	return nil
}

func (a *Arlo) put(url string, result interface{}, xcloudId string) error {
	var errorResponse ErrorResponse
	resp, err := a.getBaseRequest(nil, result, &errorResponse, xcloudId).
		Put(url)
	if err != nil {
		return err
	}
	if resp.IsError() {
		return fmt.Errorf(errorResponse.Reason)
	}
	return nil
}

func (a *Arlo) Login(ctx context.Context, user string, pass string) error {
	var loginResponse LoginResponse
	err := a.post(LoginV2Uri, map[string]string{
		"email":    user,
		"password": pass,
	}, &loginResponse, "")
	if err != nil {
		return fmt.Errorf("posting login request: %v", err)
	}
	if !loginResponse.Success {
		return fmt.Errorf("no success but no error")
	}
	a.Account = loginResponse.Data
	a.client.SetHeader("Authorization", a.Account.Token)

	var response DeviceResponse
	err = a.get(fmt.Sprintf(DevicesUri, time.Now().Format("20060102")), &response)
	if err != nil {
		return err
	}
	if !response.Success {
		return fmt.Errorf("no success but no error")
	}
	if len(response.Data) == 0 {
		return fmt.Errorf("no device found")
	}

	a.Basestations = nil
	a.Cameras = nil
	for _, device := range response.Data {
		if device.IsBasestation() {
			a.Basestations = append(a.Basestations, NewBaseStation(a, device))
			continue
		}
		if device.IsCamera() {
			a.Cameras = append(a.Cameras, NewCamera(a, device))
		}
	}

	if err := a.Subscribe(ctx); err != nil {
		return fmt.Errorf("subscribing to event stream: %v", err)
	}

	go func(ctx context.Context) {
		ticker := time.NewTicker(pingTime)
		for {
			select {
			case <-ctx.Done():
				return
			case _ = <-ticker.C:
				if err := a.Ping(ctx); err != nil {
					log.Errorf("Pingloop > error while pinging: %v > disconnect event stream", err)
					_ = a.Disconnect()
					return
				}
			}
		}
	}(ctx)

	return nil
}

func (a *Arlo) Logout() error {

	var response BaseResponse
	err := a.put(LogoutUri, &response, "")
	if err != nil {
		return err
	}
	if !response.Success {
		return fmt.Errorf("no success but no error")
	}
	return nil
}

func (a *Arlo) GetSession() (Session, error) {
	var response SessionResponse
	err := a.get(SessionUri, &response)
	if err != nil {
		return Session{}, err
	}
	if !response.Success {
		return Session{}, fmt.Errorf("no success but no error")
	}
	return response.Data, nil
}

// GetProfile returns the user profile for the currently logged in user.
func (a *Arlo) GetProfile() (*UserProfile, error) {
	var response UserProfileResponse
	err := a.get(ProfileUri, &response)
	if err != nil {
		return nil, err
	}
	if !response.Success {
		return nil, fmt.Errorf("no success but no error")
	}
	return &response.Data, nil
}

func (a *Arlo) GetBaseStation(deviceId string) *Basestation {
	for _, basestation := range a.Basestations {
		if basestation.DeviceId == deviceId {
			return basestation
		}
	}
	return nil
}

func (a *Arlo) makeEventStreamRequest(ctx context.Context, payload EventStreamPayload, xcloudid string) (*EventStreamResponse, error) {

	if !a.IsConnected() {
		log.Infof("event stream not connected: reconnecting")
		err := a.Subscribe(ctx)
		if err != nil {
			return nil, fmt.Errorf("reconnecting to event stream: %v", err)
		}
	}

	transId := genTransId()
	payload.TransId = transId

	responseChan := a.eventStream.subscribeTransaction(transId)

	// Send the payload to the event stream.
	if err := a.NotifyEventStream(payload, xcloudid); err != nil {
		return nil, fmt.Errorf("notifying event stream: %v", err)
	}
	timer := time.NewTimer(eventStreamTimeout)

	select {
	case response := <-responseChan:
		return response, nil
	case err := <-a.eventStream.Error:
		return nil, fmt.Errorf("event stream error: %v", err)
	case <-a.eventStream.disconnectedChan:
		log.Warn("event stream was closed before response was read")
		return a.makeEventStreamRequest(ctx, payload, xcloudid)
	case <-timer.C:
		return nil, fmt.Errorf("event stream response timed out after %.0f second", eventStreamTimeout.Seconds())
	}
}

func (a *Arlo) IsConnected() bool {
	select {
	case <-a.eventStream.disconnectedChan:
		return false
	default:
		return true
	}
}

func (a *Arlo) Subscribe(ctx context.Context) error {
	a.eventStream = newEventStream(
		BaseUrl+fmt.Sprintf(NotifyResponsesPushServiceUri),
		&http.Client{Jar: a.client.GetClient().Jar},
		a.client.Header.Get("Authorization"),
	)

	err := a.eventStream.listen(ctx)
	if err != nil {
		return fmt.Errorf("setting up event stream: %v", err)
	}

connectedloop:
	for {
		select {
		case <-ctx.Done():
			return fmt.Errorf("failed to subscribe to the event stream: requesting shutdown")
		case <-a.eventStream.disconnectedChan:
			return fmt.Errorf("failed to subscribe to the event stream: disconnected")
		default:
			if a.eventStream.GetIsConnected() {
				break connectedloop
			}
			time.Sleep(100 * time.Millisecond)
		}
	}

	if err := a.Ping(ctx); err != nil {
		_ = a.Disconnect()
		return fmt.Errorf("pingloop > error while pinging: %v > disconnect event stream", err)
	}

	for _, camera := range a.Cameras {
		camera.subscribeToStateUpdate()
	}

	return nil
}

func (a *Arlo) Unsubscribe(xcloudid string) error {
	var response BaseResponse
	err := a.put(UnsubscribeUri, &response, xcloudid)
	if err != nil {
		return err
	}
	if !response.Success {
		return fmt.Errorf("no success but no error")
	}
	return nil
}

func (a *Arlo) Disconnect() error {
	// disconnect channel to stop event stream.
	if a.eventStream != nil {
		a.eventStream.disconnect()
	}
	return nil
}

// Ping makes a call to the subscriptions endpoint. The Arlo event stream requires this message to be sent every 30s.

func (a *Arlo) NotifyEventStream(payload EventStreamPayload, xcloudId string) error {
	var response ErrorResponse
	err := a.post(fmt.Sprintf(NotifyUri, payload.To), payload, &response, xcloudId)
	if err != nil {
		return err
	}
	if !response.Success {
		if response.Reason != "" {
			return fmt.Errorf(response.Reason)
		} else {
			return fmt.Errorf("no success but no error")
		}
	}
	return nil
}

func (a *Arlo) makeRequest(ctx context.Context, deviceId string, xcloudid string, action string, resource string, publishResponse bool, properties interface{}, result interface{}) error {
	payload := EventStreamPayload{
		Action:          action,
		Resource:        resource,
		PublishResponse: publishResponse,
		Properties:      properties,
		From:            fmt.Sprintf("%s_%s", a.Account.UserId, TransIdPrefix),
		To:              deviceId,
	}
	resp, err := a.makeEventStreamRequest(ctx, payload, xcloudid)
	if err != nil {
		return fmt.Errorf("making event stream request: %v", err)
	}
	if result != nil {
		err = json.Unmarshal(resp.RawProperties, result)
		if err != nil {
			return fmt.Errorf("unmarshalling properties: %v", err)
		}
	}
	return nil
}

func (a *Arlo) Ping(ctx context.Context) error {
	var devices []string
	var xcloudid string
	for _, basestation := range a.Basestations {
		devices = append(devices, basestation.DeviceId)
		xcloudid = basestation.XCloudId
	}
	if len(devices) == 0 {
		return fmt.Errorf("no basestation registered")
	}
	err := a.makeRequest(ctx, devices[0], xcloudid, "set", fmt.Sprintf("subscriptions/%s_%s", a.Account.UserId, TransIdPrefix), false, map[string][]string{"devices": devices}, nil)
	if err != nil {
		return err
	}
	return nil
}