hystrix.scala

import com.netflix.hystrix.{HystrixCommandGroupKey, HystrixCommand}
import rx.Subscriber

import scala.concurrent.{Future, Promise}

package object hystrix {
  implicit class HystrixCommandToFuture[A](val cmd: HystrixCommand[A]) extends AnyVal {
    def futureNoRepeat: Future[A] = {
      val p = Promise[A]()
      cmd.observe().subscribe(new Subscriber[A]() {
        override def onError(e: Throwable): Unit = p.failure(e)

        override def onCompleted(): Unit = ()

        override def onNext(t: A): Unit = p.success(t)
      })
      p.future
    }
  }

  implicit class StringHystrixOps(val s: String) extends AnyVal {
    def asKey = HystrixCommandGroupKey.Factory.asKey(s)
  }

  implicit class ByNameOps[B](f: => B) {
    def command(key: String = "byName"): HystrixCommand[B] = new HystrixCommand[B](key.asKey) {
      override def run(): B = f
    }

    def commandWithFallback(key: String = "byNameFallback")(f2: => B) = new HystrixCommand[B](key.asKey) {
      override def run(): B = f

      override def getFallback: B = f2
    }
  }

  implicit class Function1Ops[A,B](val f: A => B) extends AnyVal {
    def command(a: A, key: String = "function1"): HystrixCommand[B] = new HystrixCommand[B](key.asKey) {
      override def run(): B = f(a)
    }

    def commandWithFallback(a: A, key: String = "function1Fallback")(f2: => B) = new HystrixCommand[B](key.asKey) {
      override def run(): B = f(a)

      override def getFallback: B = f2
    }

    def commandWithFallback1(a: A, key: String = "function1Fallback")(f2: A => B) = new HystrixCommand[B](key.asKey) {
      override def run(): B = f(a)

      override def getFallback: B = f2(a)
    }
  }
}