package com.github.mgifos.workouts

import java.time.LocalDate

import akka.actor.{Actor, ActorRef, ActorSystem, Props}
import akka.http.scaladsl.Http
import akka.http.scaladsl.client.RequestBuilding._
import akka.http.scaladsl.model.ContentTypes._
import akka.http.scaladsl.model.HttpMethods._
import akka.http.scaladsl.model.StatusCodes._
import akka.http.scaladsl.model.Uri.Query
import akka.http.scaladsl.model._
import akka.http.scaladsl.model.headers._
import akka.pattern.ask
import akka.stream.scaladsl.{Flow, Sink, Source}
import akka.stream.{Materializer, ThrottleMode}
import akka.util.Timeout
import com.github.mgifos.workouts.GarminConnect._
import com.github.mgifos.workouts.model.WorkoutDef
import com.typesafe.scalalogging.Logger
import play.api.libs.json.{JsObject, Json}

import scala.collection.immutable.{Map, Seq}
import scala.concurrent.duration._
import scala.concurrent.{ExecutionContext, Future}
import scala.language.implicitConversions
import scala.util.Failure

case class GarminWorkout(name: String, id: Long)

case class GarminSession(headers: Seq[HttpHeader])

class GarminConnect(email: String, password: String)(implicit system: ActorSystem, executionContext: ExecutionContext, mat: Materializer) {

  case class Login(forceNewSession: Boolean)

  private val log = Logger(getClass)

  /**
    * Creates workout definitions
    *
    * @param workouts
    * @return
    */
  def createWorkouts(workouts: Seq[WorkoutDef])(implicit session: GarminSession): Future[Seq[GarminWorkout]] = {

    log.info("\nCreating workouts:")
    val source = Source(workouts.map { workout =>
      val req = Post("https://connect.garmin.com/modern/proxy/workout-service/workout")
        .withEntity(HttpEntity(`application/json`, workout.json().toString()))
        .withHeaders(
          session.headers
            :+ Referer("https://connect.garmin.com/modern/workout/create/running")
            :+ RawHeader("NK", "NT"))
      workout.name -> req
    })
    val flow = Flow[(String, HttpRequest)].throttle(1, 1.second, 1, ThrottleMode.shaping).mapAsync(1) {
      case (workout, req) =>
        Http().singleRequest(req).flatMap { res =>
          if (res.status == OK) {
            res.body.map { json =>
              log.info(s"  $workout")
              GarminWorkout(workout, Json.parse(json).\("workoutId").as[Long])
            }
          } else {
            log.debug(s"Creation wo response: $res")
            Future.failed(new Error("Cannot create workout"))
          }
        }
    }
    source.via(flow).runWith(Sink.seq)
  }

  /**
    * Deletes workouts with provided names
    *
    * @param workouts Workout names
    * @return Count of deleted items
    */
  def deleteWorkouts(workouts: Seq[String])(implicit session: GarminSession): Future[Int] = {

    val futureRequests = getWorkoutsMap().map { wsMap =>
      log.info("\nDeleting workouts:")
      for {
        workout <- workouts
        ids = wsMap.getOrElse(workout, Seq.empty)
        if ids.nonEmpty
      } yield {
        val label = s"$workout -> ${ids.mkString("[", ", ", "]")}"
        label -> ids.map(
          id =>
            Post(s"https://connect.garmin.com/modern/proxy/workout-service/workout/$id").withHeaders(
              session.headers
                :+ Referer("https://connect.garmin.com/modern/workouts")
                :+ RawHeader("NK", "NT")
                :+ RawHeader("X-HTTP-Method-Override", "DELETE")))
      }
    }
    val source = Source.fromFuture(futureRequests).flatMapConcat(Source(_)).throttle(1, 1.second, 1, ThrottleMode.shaping).mapAsync(1) {
      case (label, reqs) =>
        val statusesFut = Future.sequence(reqs.map(req => Http().singleRequest(req).withoutBody))
        statusesFut.map { statuses =>
          if (statuses.forall(_.status == NoContent)) log.info(s"  $label")
          else log.error(s"  Cannot delete workout: $label")
        }
    }
    source.runWith(Sink.seq).map(_.length)
  }

  def schedule(spec: Seq[(LocalDate, GarminWorkout)])(implicit session: GarminSession): Future[Int] = {
    log.debug(s"  Scheduling spec: ${spec.mkString("\n")}")
    log.info("\nScheduling:")
    Source(spec).map {
      case (date, gw) =>
        s"$date -> ${gw.name}" -> Post(s"https://connect.garmin.com/modern/proxy/workout-service/schedule/${gw.id}")
          .withHeaders(session.headers
            :+ Referer("https://connect.garmin.com/modern/calendar")
            :+ RawHeader("NK", "NT"))
          .withEntity(HttpEntity(`application/json`, Json.obj("date" -> date.toString).toString))
    }.throttle(1, 1.second, 1, ThrottleMode.shaping)
      .mapAsync(1) {
        case (label, req) =>
          Http().singleRequest(req).withoutBody.map { res =>
            log.debug(s"  Received $res")
            if (res.status == OK) log.info(s"  $label")
            else log.error(s"  Cannot schedule: $label")
          }
      }
      .runWith(Sink.seq)
      .map(_.length)
  }

  /**
    * Retrieves workout mapping: name -> Seq[id] @ GarminConnect
    * @return
    */
  private def getWorkoutsMap()(implicit session: GarminSession): Future[Map[String, Seq[Long]]] = {

    val req = Get("https://connect.garmin.com/modern/proxy/workout-service/workouts?start=1&limit=9999&myWorkoutsOnly=true&sharedWorkoutsOnly=false")
      .withHeaders(
        session.headers
          :+ Referer("https://connect.garmin.com/modern/workouts")
          :+ RawHeader("NK", "NT"))
    val source = Source.fromFuture(Http().singleRequest(req).flatMap { res =>
      if (res.status == OK)
        res.body.map { json =>
          Json
            .parse(json)
            .asOpt[Seq[JsObject]]
            .map { arr =>
              arr.map(x => (x \ "workoutName").as[String] -> (x \ "workoutId").as[Long])
            }
            .getOrElse(Seq.empty)
            .groupBy { case (name, _) => name }
            .map { case (a, b) => a -> b.map(_._2) }
        } else {
        log.debug(s"Cannot retrieve workout list, response: $res")
        Future.failed(new Error("Cannot retrieve workout list from Garmin Connect"))
      }
    })
    source.runWith(Sink.head)
  }

  private lazy val loginActor: ActorRef = system.actorOf(Props(new LoginActor()))

  def login(forceNewSession: Boolean = false): Future[Either[String, GarminSession]] =
    ask(loginActor, Login(forceNewSession))(Timeout(2.minutes)).mapTo[Either[String, GarminSession]]

  /**
    * Holds and reloads session if neccessary
    */
  class LoginActor extends Actor {

    private case class NewSession(session: GarminSession)

    var maybeSession: Option[GarminSession] = None

    override def receive = {

      case Login(force) =>
        val origin = sender()
        maybeSession match {
          case Some(s) if !force => origin ! s
          case _ =>
            login.andThen {
              case util.Success(x) =>
                if (x.headers.exists(_.value().matches("""SESSIONID=[a-z\d-]{5,}"""))) {
                  origin ! Right(x)
                  self ! NewSession(x)
                } else
                  origin ! Left("Login was not successful, check your username and password and try again.")
              case Failure(_) =>
                origin ! Left("Attempt to log in to Garmin Connect was not successful (this could be a server error).")
            }
        }

      case NewSession(session) =>
        if (maybeSession.isEmpty) log.info("Successfully logged in to Garmin Connect!")
        maybeSession = Option(session)
    }

    private def login: Future[GarminSession] = {

      def extractCookies(res: HttpResponse) = res.headers.collect { case x: `Set-Cookie` => x.cookie }.map(c => Cookie(c.name, c.value))

      def redirectionLoop(count: Int, url: String, acc: Seq[Cookie]): Future[Seq[Cookie]] = {
        val req = HttpRequest(uri = Uri(url)).withHeaders(acc)
        log.debug(s"Login redirection no $count with req: $req")
        Http().singleRequest(req).withoutBody.flatMap { res =>
          log.debug(s"Res: $res")
          val cookies = extractCookies(res)
          res.headers.find(_.name() == "Location") match {
            case Some(header) =>
              if (count < 7) {
                val path = header.value()
                val base = path.split("/").take(3).mkString("/")
                val nextUrl = if (path.startsWith("/")) base + path else path
                redirectionLoop(count + 1, nextUrl, acc ++ cookies)
              } else {
                Future.successful(acc ++ cookies)
              }
            case None => Future.successful(acc ++ cookies)
          }
        }
      }

      val params = Map(
        "clientId" -> "GarminConnect",
        //"connectLegalTerms" -> "true",
        "consumeServiceTicket" -> "false",
        //"createAccountShown" -> "true",
        //"cssUrl" -> "https://static.garmincdn.com/com.garmin.connect/ui/css/gauth-custom-v1.2-min.css",
        //"displayNameShown" -> "false",
        //"embedWidget" -> "false",
        "gauthHost" -> "https://sso.garmin.com/sso",
        //"generateExtraServiceTicket" -> "false",
        //"generateNoServiceTicket" -> "false",
        //"globalOptInChecked" -> "false",
        //"globalOptInShown" -> "true",
        //"id" -> "gauth-widget",
        //"initialFocus" -> "true",
        //"locale" -> "en_US",
        //"locationPromptShown" -> "true",
        //"mobile" -> "false",
        //"openCreateAccount" -> "false",
        //"privacyStatementUrl" -> "//connect.garmin.com/en-US/privacy/",
        //"redirectAfterAccountCreationUrl" -> "https://connect.garmin.com/modern/",
        //"redirectAfterAccountLoginUrl" -> "https://connect.garmin.com/modern/",
        //"rememberMeChecked" -> "false",
        //"rememberMeShown" -> "true",
        "service" -> "https://connect.garmin.com/modern"
        //"source" -> "https://connect.garmin.com/en-US/signin",
        //"webhost" -> "https://connect.garmin.com"
      )
      for {
        res1 <- Http().singleRequest(HttpRequest(uri = Uri("https://sso.garmin.com/sso/login").withQuery(Query(params)))).withoutBody
        res2 <- Http()
          .singleRequest(
            HttpRequest(
              POST,
              Uri("https://sso.garmin.com/sso/signin").withQuery(Query(params)),
              entity = FormData(Map("username" -> email, "password" -> password, "embed" -> "false")).toEntity
            ).withHeaders(extractCookies(res1)).withHeaders(Origin("https://sso.garmin.com")))
          .withoutBody
        sessionCookies <- redirectionLoop(0, "https://connect.garmin.com/modern", extractCookies(res2))
      } yield GarminSession(sessionCookies)
    }
  }
}

object GarminConnect {

  class HttpResponseWithBody(original: HttpResponse) {
    def body(implicit ec: ExecutionContext, mat: Materializer): Future[String] = original.entity.toStrict(10.seconds).map(_.data.utf8String)
  }

  class LiteHttpFuture(original: Future[HttpResponse]) {
    def withoutBody(implicit ec: ExecutionContext, mat: Materializer) = original.andThen {
      case util.Success(res) => res.discardEntityBytes()
    }
  }

  implicit def responseWithBody(original: HttpResponse): HttpResponseWithBody = new HttpResponseWithBody(original)
  implicit def liteHttpFuture(original: Future[HttpResponse]): LiteHttpFuture = new LiteHttpFuture(original)
}