module Data.Iteratee.ZoomCache (
Stream(..)
, iterHeaders
, enumCacheFile
, enumStream
, mapStream
, mapPackets
, mapSummaries
) where
import Control.Applicative ((<$>))
import Control.Monad (replicateM)
import Control.Monad.Trans (MonadIO)
import qualified Data.ByteString.Lazy as L
import Data.Int
import Data.IntMap (IntMap)
import qualified Data.IntMap as IM
import Data.Iteratee (Iteratee)
import qualified Data.Iteratee as I
import qualified Data.Iteratee.ListLike as LL
import Data.Maybe
import Data.Word
import Data.Iteratee.ZoomCache.Utils
import Data.ZoomCache.Common
import Data.ZoomCache.Format
import Data.ZoomCache.Types
import Data.ZoomCache.Double()
import Data.ZoomCache.Int()
data Stream =
StreamPacket
{ strmFile :: CacheFile
, strmTrack :: TrackNo
, strmPacket :: Packet
}
| StreamSummary
{ strmFile :: CacheFile
, strmTrack :: TrackNo
, strmSummary :: ZoomSummary
}
| StreamNull
instance LL.Nullable Stream where
nullC StreamNull = True
nullC _ = False
instance LL.NullPoint Stream where
empty = StreamNull
enumCacheFile :: (Functor m, MonadIO m)
=> I.Enumeratee [Word8] Stream m a
enumCacheFile iter = do
fi <- iterHeaders
enumStream fi iter
enumStream :: (Functor m, MonadIO m)
=> CacheFile
-> I.Enumeratee [Word8] Stream m a
enumStream = I.unfoldConvStream go
where
go :: (Functor m, MonadIO m)
=> CacheFile
-> Iteratee [Word8] m (CacheFile, Stream)
go cf = do
header <- I.joinI $ I.takeUpTo 8 I.stream2list
case parseHeader (L.pack header) of
Just PacketHeader -> do
(trackNo, packet) <- readPacket (cfSpecs cf)
return (cf, StreamPacket cf trackNo (fromJust packet))
Just SummaryHeader -> do
(trackNo, summary) <- readSummaryBlock (cfSpecs cf)
return (cf, StreamSummary cf trackNo (fromJust summary))
_ -> return (cf, StreamNull)
data HeaderType = GlobalHeader | TrackHeader | PacketHeader | SummaryHeader
parseHeader :: L.ByteString -> Maybe HeaderType
parseHeader h
| h == globalHeader = Just GlobalHeader
| h == trackHeader = Just TrackHeader
| h == packetHeader = Just PacketHeader
| h == summaryHeader = Just SummaryHeader
| otherwise = Nothing
iterHeaders :: (Functor m, MonadIO m)
=> I.Iteratee [Word8] m CacheFile
iterHeaders = iterGlobal >>= go
where
iterGlobal :: (Functor m, MonadIO m)
=> Iteratee [Word8] m CacheFile
iterGlobal = do
header <- I.joinI $ I.takeUpTo 8 I.stream2list
case parseHeader (L.pack header) of
Just GlobalHeader -> mkCacheFile <$> readGlobalHeader
_ -> error "No global header"
go :: (Functor m, MonadIO m)
=> CacheFile
-> Iteratee [Word8] m CacheFile
go fi = do
header <- I.joinI $ I.takeUpTo 8 I.stream2list
case parseHeader (L.pack header) of
Just TrackHeader -> do
(trackNo, spec) <- readTrackHeader
let fi' = fi{cfSpecs = IM.insert trackNo spec (cfSpecs fi)}
if (fiFull fi')
then return fi'
else go fi'
_ -> return fi
readGlobalHeader :: (Functor m, MonadIO m) => Iteratee [Word8] m Global
readGlobalHeader = do
v <- readVersion
n <- zReadInt32
p <- readRational64
b <- readRational64
_u <- L.pack <$> (I.joinI $ I.takeUpTo 20 I.stream2list)
return $ Global v n p b Nothing
readTrackHeader :: (Functor m, MonadIO m) => Iteratee [Word8] m (TrackNo, TrackSpec)
readTrackHeader = do
trackNo <- zReadInt32
trackType <- readTrackType
drType <- readDataRateType
rate <- readRational64
byteLength <- zReadInt32
name <- L.pack <$> (I.joinI $ I.takeUpTo byteLength I.stream2list)
let spec = TrackSpec trackType drType rate name
return (trackNo, spec)
readPacket :: (Functor m, MonadIO m)
=> IntMap TrackSpec
-> Iteratee [Word8] m (TrackNo, Maybe Packet)
readPacket specs = do
trackNo <- zReadInt32
entryTime <- TS <$> zReadInt64
exitTime <- TS <$> zReadInt64
byteLength <- zReadInt32
count <- zReadInt32
packet <- case IM.lookup trackNo specs of
Just TrackSpec{..} -> do
let readTS = readTimeStamps specDRType count entryTime
case specType of
ZDouble -> do
(d :: [Double]) <- replicateM count readRaw
ts <- readTS
return . Just $
(Packet trackNo entryTime exitTime count
(ZoomRaw . fromList $ d) ts)
ZInt -> do
(d :: [Int]) <- replicateM count readRaw
ts <- readTS
return . Just $
(Packet trackNo entryTime exitTime count
(ZoomRaw . fromList $ d) ts)
Nothing -> do
I.drop byteLength
return Nothing
return (trackNo, packet)
where
readTimeStamps :: (Functor m, MonadIO m)
=> DataRateType -> Int -> TimeStamp
-> Iteratee [Word8] m [TimeStamp]
readTimeStamps drType count entry = map TS <$> case drType of
ConstantDR -> do
return $ take count [unTS entry ..]
VariableDR -> do
replicateM count zReadInt64
readSummaryBlock :: (Functor m, MonadIO m)
=> IntMap TrackSpec
-> Iteratee [Word8] m (TrackNo, Maybe ZoomSummary)
readSummaryBlock specs = do
trackNo <- zReadInt32
lvl <- zReadInt32
entryTime <- TS <$> zReadInt64
exitTime <- TS <$> zReadInt64
byteLength <- zReadInt32
summary <- case IM.lookup trackNo specs of
Just TrackSpec{..} -> do
case specType of
ZDouble -> do
(sd :: SummaryData Double) <- readSummary
return . Just . ZoomSummary $
Summary trackNo lvl entryTime exitTime sd
ZInt -> do
(sd :: SummaryData Int) <- readSummary
return . Just . ZoomSummary $
Summary trackNo lvl entryTime exitTime sd
Nothing -> do
I.drop byteLength
return Nothing
return (trackNo, summary)
mapStream :: (Functor m, MonadIO m)
=> (Stream -> m ())
-> Iteratee [Word8] m ()
mapStream = I.joinI . enumCacheFile . I.mapChunksM_
mapPackets :: (Functor m, MonadIO m)
=> (Packet -> m ())
-> Iteratee [Word8] m ()
mapPackets f = mapStream process
where
process StreamPacket{..} = f strmPacket
process _ = return ()
mapSummaries :: (Functor m, MonadIO m)
=> (ZoomSummary -> m ())
-> Iteratee [Word8] m ()
mapSummaries f = mapStream process
where
process StreamSummary{..} = f strmSummary
process _ = return ()
readVersion :: (Functor m, MonadIO m) => Iteratee [Word8] m Version
readVersion = do
vMaj <- zReadInt16
vMin <- zReadInt16
return $ Version vMaj vMin
readTrackType :: (Functor m, MonadIO m) => Iteratee [Word8] m TrackType
readTrackType = do
n <- zReadInt16
case n of
0 -> return ZDouble
1 -> return ZInt
_ -> error "Bad tracktype"
readDataRateType :: (Functor m, MonadIO m) => Iteratee [Word8] m DataRateType
readDataRateType = do
n <- zReadInt16
case n of
0 -> return ConstantDR
1 -> return VariableDR
_ -> error "Bad data rate type"