def loadProduct(id: ProductId): Future[Seq[(UUID, String, String)]] = {

  val program = for {

    (p, ns) <- productsTable

    .filter(_.id === id)

    .join(namesTable)

    .on(_.id === _.productId)

    } yield (p.id, ns.langCode, ns.name)

    dbConfig.db.run(program.result)

}

def loadProducts(): DatabasePublisher[(UUID, String, String)] = {

 val program = for {

   (p, ns) <- productsTable.join(namesTable)

   .on(_.id === _.productId).sortBy(_._1.id)

   } yield (p.id, ns.langCode, ns.name)

   dbConfig.db.stream(program.result)

}

def saveProduct(p: Product): Future[List[Int]] = {

  val cp = productsTable += (p.id)

  val program = DBIO.sequence(

    cp :: saveTranslations(p).toList

    ).transactionally

    dbConfig.db.run(program)

}

def updateProduct(p: Product): Future[List[Int]] = {

  val program = namesTable

  .filter(_.productId === p.id)

  .delete

  .andThen(DBIO.sequence(saveTranslations(p).toList))

  .transactionally 33 dbConfig.db.run(program)

  }

protected def saveTranslations(p: Product): NonEmptyList[DBIO[Int]] = {

  val save = saveTranslation(p.id)(_)

  p.names.toNonEmptyList.map(t => save(t))

  } 

/* Create a query to insert or update a given translation in the database.

* @param id The unique ID of the product.

* @param t The translation to be saved.

* @return A composable sql query for Slick.

*/

protected def saveTranslation(id: ProductId)(t: Translation): DBIO[Int] = 

  namesTable.insertOrUpdate((id, t.lang, t.name))