-- |
-- Module     : Simulation.Aivika.Dynamics.Internal.Time
-- Copyright  : Copyright (c) 2009-2013, David Sorokin <david.sorokin@gmail.com>
-- License    : BSD3
-- Maintainer : David Sorokin <david.sorokin@gmail.com>
-- Stability  : experimental
-- Tested with: GHC 7.6.3
--
-- This module defines the time parameters.
--

module Simulation.Aivika.Dynamics.Internal.Time
       (starttime, 
        stoptime, 
        dt, 
        time,
        integTimes, 
        isTimeInteg,
        integIteration,
        integPhase) where

import Simulation.Aivika.Dynamics.Internal.Simulation
import Simulation.Aivika.Dynamics.Internal.Dynamics

-- | Return the start simulation time.
starttime :: Dynamics Double
starttime = Dynamics $ return . spcStartTime . pointSpecs

-- | Return the stop simulation time.
stoptime :: Dynamics Double
stoptime = Dynamics $ return . spcStopTime . pointSpecs

-- | Return the integration time step.
dt :: Dynamics Double
dt = Dynamics $ return . spcDT . pointSpecs

-- | Return the current simulation time.
time :: Dynamics Double
time = Dynamics $ return . pointTime 

-- | Return the integration time points.
integTimes :: Specs -> [Double]
integTimes sc = map t [nl .. nu]
  where (nl, nu) = integIterationBnds sc
        t n = basicTime sc n 0
     
-- | Whether the current time is an integration time.
isTimeInteg :: Dynamics Bool
isTimeInteg = Dynamics $ \p -> return $ pointPhase p >= 0

-- | Return the integration iteration closest to the current simulation time.
integIteration :: Dynamics Int
integIteration = Dynamics $ return . pointIteration

-- | Return the integration phase for the current simulation time.
-- It is @(-1)@ for non-integration time points.
integPhase :: Dynamics Int
integPhase = Dynamics $ return . pointPhase