import cats.implicits._
import doobie.imports._
import fs2.Task
import fs2.interop.cats._

object Main extends App {
  val xa = DriverManagerTransactor[Task](
    "org.postgresql.Driver", "jdbc:postgresql:world", "postgres", ""
  )

  def insert(foos: List[(Int, String)]): ConnectionIO[Int] = {
    val q = "insert into foo (id, name) values (?, ?)"
    Update[(Int, String)](q).updateMany(foos)
  }

  def delete(min: Long, max: Long): ConnectionIO[Int] = {
    (sql"delete from foo where (id between $min and $max)").update.run
  }

  val insertIO: ConnectionIO[Int] =
    insert((1 to 100).toList.map((_, "a")))

  val deleteIO: ConnectionIO[Unit] =
    (1 to 50).grouped(10).toStream.map { ids =>
      delete(ids.min, ids.max)
    }.sequence_

  val insertTask: Task[Int] = insertIO.transact(xa)
  val deleteTask: Task[Unit] = deleteIO.transact(xa)

  //insertTask.unsafeRun
  //deleteTask.unsafeRun
}