{-# LANGUAGE MultiParamTypeClasses #-}

-- |
-- Module     : Simulation.Aivika.Experiment.Chart.TimeSeriesView
-- Copyright  : Copyright (c) 2012-2017, David Sorokin <david.sorokin@gmail.com>
-- License    : BSD3
-- Maintainer : David Sorokin <david.sorokin@gmail.com>
-- Stability  : experimental
-- Tested with: GHC 8.0.1
--
-- The module defines 'TimeSeriesView' that plots the time series charts.
--

module Simulation.Aivika.Experiment.Chart.TimeSeriesView
       (TimeSeriesView(..), 
        defaultTimeSeriesView) where

import Control.Monad
import Control.Monad.Trans
import Control.Lens

import qualified Data.Map as M
import Data.IORef
import Data.Maybe
import Data.Either
import Data.Array
import Data.List
import Data.Monoid
import Data.Default.Class

import System.IO
import System.FilePath

import Graphics.Rendering.Chart

import Simulation.Aivika
import Simulation.Aivika.Experiment
import Simulation.Aivika.Experiment.Base
import Simulation.Aivika.Experiment.Chart.Types
import Simulation.Aivika.Experiment.Chart.Utils (colourisePlotLines)

-- | Defines the 'View' that plots the time series charts.
data TimeSeriesView =
  TimeSeriesView { timeSeriesTitle       :: String,
                   -- ^ This is a title used in HTML.
                   timeSeriesDescription :: String,
                   -- ^ This is a description used in HTML.
                   timeSeriesWidth       :: Int,
                   -- ^ The width of the chart.
                   timeSeriesHeight      :: Int,
                   -- ^ The height of the chart.
                   timeSeriesFileName    :: ExperimentFilePath,
                   -- ^ It defines the file name with optional extension for each image to be saved.
                   -- It may include special variables @$TITLE@, @$RUN_INDEX@ and @$RUN_COUNT@.
                   --
                   -- An example is
                   --
                   -- @
                   --   timeSeriesFileName = UniqueFilePath \"$TITLE - $RUN_INDEX\"
                   -- @
                   timeSeriesPredicate   :: Event Bool,
                   -- ^ It specifies the predicate that defines
                   -- when we plot data in the chart.
                   timeSeriesTransform    :: ResultTransform,
                   -- ^ The transform applied to the results before receiving series.
                   timeSeriesLeftYSeries  :: ResultTransform, 
                   -- ^ It defines the series plotted basing on the left Y axis.
                   timeSeriesRightYSeries :: ResultTransform, 
                   -- ^ It defines the series plotted basing on the right Y axis.
                   timeSeriesPlotTitle    :: String,
                   -- ^ This is a title used in the chart when
                   -- simulating a single run. It may include 
                   -- special variable @$TITLE@.
                   --
                   -- An example is
                   --
                   -- @
                   --   timeSeriesPlotTitle = \"$TITLE\"
                   -- @
                   timeSeriesRunPlotTitle :: String,
                   -- ^ The run title for the chart. It is used 
                   -- when simulating multiple runs and it may 
                   -- include special variables @$RUN_INDEX@, 
                   -- @$RUN_COUNT@ and @$PLOT_TITLE@.
                   --
                   -- An example is 
                   --
                   -- @
                   --   timeSeriesRunPlotTitle = \"$PLOT_TITLE / Run $RUN_INDEX of $RUN_COUNT\"
                   -- @
                   timeSeriesPlotLines :: [PlotLines Double Double ->
                                           PlotLines Double Double],
                   -- ^ Probably, an infinite sequence of plot 
                   -- transformations based on which the plot
                   -- is constructed for each series. Generally,
                   -- it must not coincide with a sequence of 
                   -- labels as one label may denote a whole list 
                   -- or an array of data providers.
                   --
                   -- Here you can define a colour or style of
                   -- the plot lines.
                   timeSeriesBottomAxis :: LayoutAxis Double ->
                                           LayoutAxis Double,
                   -- ^ A transformation of the bottom axis, 
                   -- after title @time@ is added.
                   timeSeriesLayout :: LayoutLR Double Double Double ->
                                       LayoutLR Double Double Double
                   -- ^ A transformation of the plot layout, 
                   -- where you can redefine the axes, for example.
                 }
  
-- | The default time series view.  
defaultTimeSeriesView :: TimeSeriesView
defaultTimeSeriesView = 
  TimeSeriesView { timeSeriesTitle       = "Time Series",
                   timeSeriesDescription = "It shows the Time Series chart(s).",
                   timeSeriesWidth       = 640,
                   timeSeriesHeight      = 480,
                   timeSeriesFileName    = UniqueFilePath "TimeSeries($RUN_INDEX)",
                   timeSeriesPredicate   = return True,
                   timeSeriesTransform   = id,
                   timeSeriesLeftYSeries  = const mempty,
                   timeSeriesRightYSeries = const mempty,
                   timeSeriesPlotTitle    = "$TITLE",
                   timeSeriesRunPlotTitle = "$PLOT_TITLE / Run $RUN_INDEX of $RUN_COUNT",
                   timeSeriesPlotLines   = colourisePlotLines,
                   timeSeriesBottomAxis  = id,
                   timeSeriesLayout      = id }

instance ChartRendering r => ExperimentView TimeSeriesView (WebPageRenderer r) where
  
  outputView v = 
    let reporter exp (WebPageRenderer renderer _) dir =
          do st <- newTimeSeries v exp renderer dir
             let context =
                   WebPageContext $
                   WebPageWriter { reporterWriteTOCHtml = timeSeriesTOCHtml st,
                                   reporterWriteHtml    = timeSeriesHtml st }
             return ExperimentReporter { reporterInitialise = return (),
                                         reporterFinalise   = return (),
                                         reporterSimulate   = simulateTimeSeries st,
                                         reporterContext    = context }
    in ExperimentGenerator { generateReporter = reporter }

instance ChartRendering r => ExperimentView TimeSeriesView (FileRenderer r) where
  
  outputView v = 
    let reporter exp (FileRenderer renderer _) dir =
          do st <- newTimeSeries v exp renderer dir
             return ExperimentReporter { reporterInitialise = return (),
                                         reporterFinalise   = return (),
                                         reporterSimulate   = simulateTimeSeries st,
                                         reporterContext    = FileContext }
    in ExperimentGenerator { generateReporter = reporter }
  
-- | The state of the view.
data TimeSeriesViewState r =
  TimeSeriesViewState { timeSeriesView       :: TimeSeriesView,
                        timeSeriesExperiment :: Experiment,
                        timeSeriesRenderer   :: r,
                        timeSeriesDir        :: FilePath, 
                        timeSeriesMap        :: M.Map Int FilePath }
  
-- | Create a new state of the view.
newTimeSeries :: ChartRendering r => TimeSeriesView -> Experiment -> r -> FilePath -> ExperimentWriter (TimeSeriesViewState r)
newTimeSeries view exp renderer dir =
  do let n = experimentRunCount exp
     fs <- forM [0..(n - 1)] $ \i ->
       resolveFilePath dir $
       mapFilePath (flip replaceExtension $ renderableChartExtension renderer) $
       expandFilePath (timeSeriesFileName view) $
       M.fromList [("$TITLE", timeSeriesTitle view),
                   ("$RUN_INDEX", show $ i + 1),
                   ("$RUN_COUNT", show n)]
     liftIO $ forM_ fs $ flip writeFile []  -- reserve the file names
     let m = M.fromList $ zip [0..(n - 1)] fs
     return TimeSeriesViewState { timeSeriesView       = view,
                                  timeSeriesExperiment = exp,
                                  timeSeriesRenderer   = renderer,
                                  timeSeriesDir        = dir, 
                                  timeSeriesMap        = m }
       
-- | Plot the time series chart within simulation.
simulateTimeSeries :: ChartRendering r => TimeSeriesViewState r -> ExperimentData -> Composite ()
simulateTimeSeries st expdata =
  do let view    = timeSeriesView st
         rs1     = timeSeriesLeftYSeries view $
                   timeSeriesTransform view $
                   experimentResults expdata
         rs2     = timeSeriesRightYSeries view $
                   timeSeriesTransform view $
                   experimentResults expdata
         exts1   = resultsToDoubleValues rs1
         exts2   = resultsToDoubleValues rs2
         signals = experimentPredefinedSignals expdata
         n = experimentRunCount $ timeSeriesExperiment st
         width   = timeSeriesWidth view
         height  = timeSeriesHeight view
         predicate  = timeSeriesPredicate view
         title   = timeSeriesTitle view
         plotTitle  = timeSeriesPlotTitle view
         runPlotTitle = timeSeriesRunPlotTitle view
         plotLines  = timeSeriesPlotLines view
         plotBottomAxis = timeSeriesBottomAxis view
         plotLayout = timeSeriesLayout view
         renderer   = timeSeriesRenderer st
     i <- liftParameter simulationIndex
     let file  = fromJust $ M.lookup (i - 1) (timeSeriesMap st)
         plotTitle' = 
           replace "$TITLE" title
           plotTitle
         runPlotTitle' =
           if n == 1
           then plotTitle'
           else replace "$RUN_INDEX" (show i) $
                replace "$RUN_COUNT" (show n) $
                replace "$PLOT_TITLE" plotTitle'
                runPlotTitle
         inputHistory exts =
           forM exts $ \ext ->
           let transform () =
                 do x <- predicate
                    if x
                      then resultValueData ext
                      else return (1/0)  -- the infinite values will be ignored then
           in newSignalHistory $
              mapSignalM transform $
              pureResultSignal signals $
              resultValueSignal ext
     hs1 <- inputHistory exts1
     hs2 <- inputHistory exts2
     disposableComposite $
       DisposableEvent $
       do let plots hs exts plotLineTails =
                do ps <-
                     forM (zip3 hs exts (head plotLineTails)) $
                     \(h, ext, plotLines) ->
                     do (ts, xs) <- readSignalHistory h 
                        return $
                          toPlot $
                          plotLines $
                          plot_lines_values .~ filterPlotLinesValues (zip (elems ts) (elems xs)) $
                          plot_lines_title .~ resultValueName ext $
                          def
                   return (ps, drop (length hs) plotLineTails)
          (ps1, plotLineTails) <- plots hs1 exts1 (tails plotLines)
          (ps2, plotLineTails) <- plots hs2 exts2 plotLineTails
          let ps1' = map Left ps1
              ps2' = map Right ps2
              ps'  = ps1' ++ ps2'
              axis = plotBottomAxis $
                     laxis_title .~ "time" $
                     def
              updateLeftAxis =
                if null ps1
                then layoutlr_left_axis_visibility .~ AxisVisibility False False False
                else id
              updateRightAxis =
                if null ps2
                then layoutlr_right_axis_visibility .~ AxisVisibility False False False
                else id
              chart = plotLayout . updateLeftAxis . updateRightAxis $
                      layoutlr_x_axis .~ axis $
                      layoutlr_title .~ runPlotTitle' $
                      layoutlr_plots .~ ps' $
                      def
          liftIO $
            do renderChart renderer (width, height) file (toRenderable chart)
               when (experimentVerbose $ timeSeriesExperiment st) $
                 putStr "Generated file " >> putStrLn file
     
-- | Remove the NaN and inifity values.     
filterPlotLinesValues :: [(Double, Double)] -> [[(Double, Double)]]
filterPlotLinesValues = 
  filter (not . null) .
  divideBy (\(t, x) -> isNaN x || isInfinite x)

-- | Get the HTML code.     
timeSeriesHtml :: TimeSeriesViewState r -> Int -> HtmlWriter ()     
timeSeriesHtml st index =
  let n = experimentRunCount $ timeSeriesExperiment st
  in if n == 1
     then timeSeriesHtmlSingle st index
     else timeSeriesHtmlMultiple st index
     
-- | Get the HTML code for a single run.
timeSeriesHtmlSingle :: TimeSeriesViewState r -> Int -> HtmlWriter ()
timeSeriesHtmlSingle st index =
  do header st index
     let f = fromJust $ M.lookup 0 (timeSeriesMap st)
     writeHtmlParagraph $
       writeHtmlImage (makeRelative (timeSeriesDir st) f)

-- | Get the HTML code for multiple runs.
timeSeriesHtmlMultiple :: TimeSeriesViewState r -> Int -> HtmlWriter ()
timeSeriesHtmlMultiple st index =
  do header st index
     let n = experimentRunCount $ timeSeriesExperiment st
     forM_ [0..(n - 1)] $ \i ->
       let f = fromJust $ M.lookup i (timeSeriesMap st)
       in writeHtmlParagraph $
          writeHtmlImage (makeRelative (timeSeriesDir st) f)

header :: TimeSeriesViewState r -> Int -> HtmlWriter ()
header st index =
  do writeHtmlHeader3WithId ("id" ++ show index) $ 
       writeHtmlText (timeSeriesTitle $ timeSeriesView st)
     let description = timeSeriesDescription $ timeSeriesView st
     unless (null description) $
       writeHtmlParagraph $ 
       writeHtmlText description

-- | Get the TOC item.
timeSeriesTOCHtml :: TimeSeriesViewState r -> Int -> HtmlWriter ()
timeSeriesTOCHtml st index =
  writeHtmlListItem $
  writeHtmlLink ("#id" ++ show index) $
  writeHtmlText (timeSeriesTitle $ timeSeriesView st)