/* ===================================================
 * Copyright © 2013 the kamon project <http://kamon.io/>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ========================================================== */
package kamon.newrelic

import akka.actor.Actor
import kamon.trace.UowTrace
import com.newrelic.api.agent.{ NewRelic ⇒ NRAgent }
import kamon.trace.UowTracing.WebExternal

class Apdex extends Actor {
  val t = 500

  var satisfied: Int = 0
  var tolerating: Int = 0
  var frustrated: Int = 0

  def receive = {
    case trace: UowTrace ⇒ recordTransaction(trace)

  }

  def clearStats: Unit = {
    satisfied = 0
    tolerating = 0
    frustrated = 0
  }

  def total: Int = satisfied + tolerating + frustrated

  def updateStats(sampleTime: Double): Unit = {
    if (sampleTime < t)
      satisfied += 1
    else if (sampleTime >= t && sampleTime <= 4 * t)
      tolerating += 1
    else
      frustrated += 1
  }

  def recordTransaction(uowTrace: UowTrace): Unit = {
    val time = ((uowTrace.segments.last.timestamp - uowTrace.segments.head.timestamp) / 1E9)

    updateStats(time)

    NRAgent.recordMetric("WebTransaction/Custom" + uowTrace.name, time.toFloat)
    NRAgent.recordMetric("WebTransaction", time.toFloat)
    NRAgent.recordMetric("HttpDispatcher", time.toFloat)

    uowTrace.segments.collect { case we: WebExternal ⇒ we }.foreach { webExternalTrace ⇒
      val external = ((webExternalTrace.finish - webExternalTrace.start) / 1E9).toFloat

      println("Web External: " + webExternalTrace)
      NRAgent.recordMetric(s"External/${webExternalTrace.host}/http", external)
      NRAgent.recordMetric(s"External/${webExternalTrace.host}/all", external)
      NRAgent.recordMetric(s"External/${webExternalTrace.host}/http/WebTransaction/Custom" + uowTrace.name, external)
    }

    val allExternals = uowTrace.segments.collect { case we: WebExternal ⇒ we } sortBy (_.timestamp)

    def measureExternal(accum: Long, lastEnd: Long, segments: Seq[WebExternal]): Long = segments match {
      case Nil ⇒ accum
      case head :: tail ⇒
        if (head.start > lastEnd)
          measureExternal(accum + (head.finish - head.start), head.finish, tail)
        else
          measureExternal(accum + (head.finish - lastEnd), head.finish, tail)
    }

    val external = measureExternal(0, 0, allExternals) / 1E9

    NRAgent.recordMetric(s"External/all", external.toFloat)
    NRAgent.recordMetric(s"External/allWeb", external.toFloat)

  }
}

case object Flush