package handlers

import (
	"context"
	"net/http"

	"github.com/fiskerinc/cloud-services/services/gateway/services"

	"github.com/fiskerinc/cloud-services/services/gateway/websocket"

	"github.com/fiskerinc/cloud-services/pkg/logger"
	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
)

// SecureSessionWebsocketHandler initiates a websocket connection off an HTTP request
func SecureSessionWebsocketHandler(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	session, err := websocket.NewSecureSession(w, r)
	if err != nil {
		logger.Warn().Err(err).Send()
		logger.Warn().Msgf("wshandler: bad request %v", websocket.PrintRequest(r))
		return
	}

	go runSessionLifeCycle(ctx, session)
}

// InsecureSessionWebsocketHandler initiates a websocket connection off an HTTP request from mobile
func InsecureSessionWebsocketHandler(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	session, err := websocket.NewInsecureSession(w, r)
	if err != nil {
		logger.Warn().Err(err).Send()
		logger.Warn().Msgf("wshandler: bad request %v", websocket.PrintRequest(r))
		return
	}

	go runSessionLifeCycle(ctx, session)
}

// WebsocketSession handles the life cycle of a websocket
func runSessionLifeCycle(ctx context.Context, session websocket.SessionInterface) {
	defer session.Close()
	span, ctx := tracer.StartSpanFromContext(ctx, "websocket")
	defer span.Finish()
	err := session.Authenticate()
	if err != nil {
		logger.At(logger.Warn(), session.Key(), "conn").Str("ip", session.GetIP()).Err(err).Send()
		return
	}
	addServices(session)
	defer removeServices(session)
	producer, err := services.GetKafkaProducer()
	if err != nil {
		logger.Error().Str("id", session.Key()).Err(err).Send()
		return
	}
	logger.Debug().Msgf("websocket session: start listening%v", session.GetID())
	err = session.Listen(ctx, producer)
	if err != nil {
		logger.At(logger.Warn(), session.Key(), "conn").Err(err).Send()
		return
	}
}

// addServices notifies all services upon websocket connection
func addServices(session websocket.SessionInterface) error {
	id := session.Key()

	services.GetConnections().Add(session)

	logger.Debug().Msgf("websocket session: addServices lifecycle %v", id)
	services.AddRemoveRedisListeners(true, id)
	producer, err := services.GetKafkaProducer()
	if err != nil {
		logger.At(logger.Error(), session.Key(), "Kafka producer failed").Err(err).Send()
		return err
	}
	if err = session.Load(producer); err != nil {
		logger.At(logger.Warn(), session.Key(), "conn").Err(err).Send()
	}
	logger.At(logger.Debug(), "Session", id).Msgf("connection added %s", id)
	return nil
}

// removeServices notifies all services upon websocket disconnection
func removeServices(session websocket.SessionInterface) error {
	id := session.Key()

	if err := services.GetConnections().Remove(session); err != nil {
		// if error returned, the session did not exist or is different session
		// that means we should not remove the current id from pub sub and queues
		logger.At(logger.Error(), session.Key(), "conn").Err(err).Send()
		return err
	}

	services.AddRemoveRedisListeners(false, id)
	producer, err := services.GetKafkaProducer()
	if err != nil {
		logger.At(logger.Error(), session.Key(), "Kafka producer").Err(err).Send()
		return err
	}

	if err = session.Teardown(producer); err != nil {
		logger.At(logger.Warn(), session.Key(), "conn").Err(err).Send()
	}
	logger.At(logger.Debug(), "Session", id).Msgf("connection removed %s", id)
	return nil
}