-- |
-- Module : Simulation.Aivika.Trans.Arrival
-- Copyright : Copyright (c) 2009-2017, David Sorokin
-- License : BSD3
-- Maintainer : David Sorokin
-- Stability : experimental
-- Tested with: GHC 8.0.1
--
-- This module defines the types and functions for working with the events
-- that can represent something that arrive from outside the model, or
-- represent other things which computation is delayed and hence is not synchronized.
--
-- Therefore, the additional information is provided about the time and delay of arrival.
module Simulation.Aivika.Trans.Arrival
(Arrival(..),
ArrivalTimer,
newArrivalTimer,
arrivalTimerProcessor,
arrivalTimerSignal,
arrivalTimerChannel,
arrivalProcessingTime,
arrivalProcessingTimeChanged,
arrivalProcessingTimeChanged_,
resetArrivalTimer) where
import Control.Monad
import Control.Monad.Trans
import Simulation.Aivika.Trans.Comp
import Simulation.Aivika.Trans.Simulation
import Simulation.Aivika.Trans.Dynamics
import Simulation.Aivika.Trans.Event
import Simulation.Aivika.Trans.Composite
import Simulation.Aivika.Trans.Processor
import Simulation.Aivika.Trans.Stream
import Simulation.Aivika.Trans.Statistics
import Simulation.Aivika.Trans.Ref
import Simulation.Aivika.Trans.Signal
import Simulation.Aivika.Trans.Channel
import Simulation.Aivika.Trans.DES
import Simulation.Aivika.Arrival (Arrival(..))
-- | Accumulates the statistics about that how long the arrived events are processed.
data ArrivalTimer m =
ArrivalTimer { arrivalProcessingTimeRef :: Ref m (SamplingStats Double),
arrivalProcessingTimeChangedSource :: SignalSource m () }
-- | Create a new timer that measures how long the arrived events are processed.
newArrivalTimer :: MonadDES m => Simulation m (ArrivalTimer m)
{-# INLINABLE newArrivalTimer #-}
newArrivalTimer =
do r <- newRef emptySamplingStats
s <- newSignalSource
return ArrivalTimer { arrivalProcessingTimeRef = r,
arrivalProcessingTimeChangedSource = s }
-- | Return the statistics about that how long the arrived events were processed.
arrivalProcessingTime :: MonadDES m => ArrivalTimer m -> Event m (SamplingStats Double)
{-# INLINABLE arrivalProcessingTime #-}
arrivalProcessingTime = readRef . arrivalProcessingTimeRef
-- | Return a signal raised when the the processing time statistics changes.
arrivalProcessingTimeChanged :: MonadDES m => ArrivalTimer m -> Signal m (SamplingStats Double)
{-# INLINABLE arrivalProcessingTimeChanged #-}
arrivalProcessingTimeChanged timer =
mapSignalM (const $ arrivalProcessingTime timer) (arrivalProcessingTimeChanged_ timer)
-- | Return a signal raised when the the processing time statistics changes.
arrivalProcessingTimeChanged_ :: MonadDES m => ArrivalTimer m -> Signal m ()
{-# INLINABLE arrivalProcessingTimeChanged_ #-}
arrivalProcessingTimeChanged_ timer =
publishSignal (arrivalProcessingTimeChangedSource timer)
-- | Return a processor that actually measures how much time has passed from
-- the time of arriving the events.
arrivalTimerProcessor :: MonadDES m => ArrivalTimer m -> Processor m (Arrival a) (Arrival a)
{-# INLINABLE arrivalTimerProcessor #-}
arrivalTimerProcessor timer =
Processor $ \xs -> Cons $ loop xs where
loop xs =
do (a, xs) <- runStream xs
liftEvent $
do t <- liftDynamics time
modifyRef (arrivalProcessingTimeRef timer) $
addSamplingStats (t - arrivalTime a)
triggerSignal (arrivalProcessingTimeChangedSource timer) ()
return (a, Cons $ loop xs)
-- | Return a signal that actually measures how much time has passed from
-- the time of arriving the events.
--
-- Note that the statistics is counted each time you subscribe to the output signal.
-- For example, if you subscribe twice then the statistics counting is duplicated.
-- Ideally, you should subscribe to the output signal only once.
arrivalTimerSignal :: MonadDES m => ArrivalTimer m -> Signal m (Arrival a) -> Signal m (Arrival a)
{-# INLINABLE arrivalTimerSignal #-}
arrivalTimerSignal timer sa =
Signal { handleSignal = \h ->
handleSignal sa $ \a ->
do t <- liftDynamics time
modifyRef (arrivalProcessingTimeRef timer) $
addSamplingStats (t - arrivalTime a)
h a
}
-- | Like 'arrivalTimerSignal' but measures how much time has passed from
-- the time of arriving the events in the channel.
arrivalTimerChannel :: MonadDES m => ArrivalTimer m -> Channel m (Arrival a) (Arrival a)
{-# INLINABLE arrivalTimerChannel #-}
arrivalTimerChannel timer =
Channel $ \sa ->
return $ arrivalTimerSignal timer sa
-- | Reset the statistics.
resetArrivalTimer :: MonadDES m => ArrivalTimer m -> Event m ()
{-# INLINABLE resetArrivalTimer #-}
resetArrivalTimer timer =
do writeRef (arrivalProcessingTimeRef timer) emptySamplingStats
triggerSignal (arrivalProcessingTimeChangedSource timer) ()