package services.auctions

import dao.{AuctionsDAO, UsersDAO}
import models.Auction
import play.api.libs.functional.syntax.toFunctionalBuilderOps
import play.api.libs.json.{JsPath, JsResult, Reads}

import java.time.Instant
import javax.inject.Inject
import scala.concurrent.{ExecutionContext, Future}

object NewBid {
  case class Request(bid: BigDecimal, bidderGid: String, timestamp: Instant)

  given Reads[Request] = (
    (JsPath \ "bid").read[BigDecimal] and
      (JsPath \ "bidder_gid").read[String] and
      (JsPath \ "timestamp").read[Instant]
    )(Request.apply)
}

class NewBid @Inject()(auctionsDao: AuctionsDAO, usersDAO: UsersDAO)(using ec: ExecutionContext) {
  import NewBid.Request

  def perform(auctionGid: String, request: Request): Future[Option[Auction]] = {
    val dataFuture = for {
      auction <- auctionsDao.find_by_gid(auctionGid)
      bidder <- usersDAO.find_by_gid(request.bidderGid)
    } yield (auction, bidder)

    dataFuture.flatMap {
      case (Some(auction), Some(bidder)) =>
        auctionsDao.newBid(auction, bidder, bid = request.bid, timestamp = request.timestamp)
      case (_, _) =>
        // One of them (or both) aren't found
        Future.successful(None)
    }
  }
}