shares are now lenses

[mTask.git] / Shares / mTaskShare.icl

diff --git a/Shares/mTaskShare.icl b/Shares/mTaskShare.icl
index c22843f..81ebb8b 100644 (file)
--- a/Shares/mTaskShare.icl
+++ b/Shares/mTaskShare.icl
@@ -13,7 +13,7 @@ from StdFunc import flip
 derive class iTask MTaskShare
 
 manageShares :: Task [MTaskDevice]
-manageShares = whileUnchanged (sdsFocus (Just -1) deviceStore)
+manageShares = whileUnchanged deviceStoreNP
        $ \devs->case devs of
                [] = viewInformation "No devices yet" [] []
                _ = allTasks (map manageSharesOnDevice devs)
@@ -25,7 +25,7 @@ manageSharesOnDevice dev = (case dev.deviceShares of
        ) >>| treturn dev
 
 updateShares :: MTaskDevice ([MTaskShare] -> [MTaskShare]) -> Task [MTaskShare]
-updateShares dev tfun = upd (map upFun) (sdsFocus (Just -1) deviceStore)
+updateShares dev tfun = upd (map upFun) (sdsFocus (Just (dev, -1)) deviceStore)
                @ (\d->d.deviceShares) o fromJust o find ((==)dev)
        where
                upFun d = if (dev == d) ({d&deviceShares=tfun d.deviceShares}) d
@@ -89,41 +89,35 @@ instance == MTaskShare where
        (==) a b = a.identifier == b.identifier
 
 getRealShare :: MTaskDevice MTaskShare -> Shared BCValue
-getRealShare dev share=:{identifier} = sdsFocus (Just identifier) $ SDSSource {SDSSource
-       | name = "mTaskShareMap-" +++ toString identifier, read=rr, write=ww}
-       where
-               rr name iworld = case read (sdsFocus (Just identifier) deviceStore) iworld of
-                       (Error e, iworld) = (Error e, iworld)
-                       (Ok devices, iworld) = case find ((==)dev) devices of
-                               Nothing = (Error $ exception "Device doesn't exist anymore", iworld)
-                               Just {deviceShares} = case find ((==)share) deviceShares of
-                                       Nothing = (Error $ exception "Share doesn't exist", iworld)
-                                       Just s = (Ok s.MTaskShare.value, iworld)
-                       
-               // Also send messages
-               ww name value iworld
-               | not (trace_tn ("Update to: " +++ printToString value)) = undef
-               = case modify (tuple () o modifyValue value) (sdsFocus (Just identifier) deviceStore) iworld of
-                       (Error e, iworld) = (Error e, iworld)
-                       (Ok _, iworld) = case sendMessagesIW [MTUpd identifier value] dev iworld of
-                               (Error e, iworld) = (Error e, iworld)
-                               (Ok _, iworld) = (Ok $ const True, iworld)
-
-               modifyValue :: BCValue [MTaskDevice] -> [MTaskDevice]
-               modifyValue v ds = filterMap ((==)dev) (updateShare identifier v) ds
-
-filterMap :: (a -> Bool) (a -> a) [a] -> [a]
-filterMap f t xs = [if (f x) (t x) x\\x<-xs]
-
-getDeviceStoreForShare :: Int -> Shared [MTaskDevice]
-getDeviceStoreForShare ident = sdsFocus (Just ident) $ deviceStore
-
-updateShareFromPublish :: MTaskDevice Int BCValue -> Task [MTaskDevice]
-updateShareFromPublish dev ident val 
-       = upd (filterMap ((==)dev) (updateShare ident val)) $ getDeviceStoreForShare ident
-
-updateShare :: Int BCValue MTaskDevice -> MTaskDevice
-updateShare ident val dev = {MTaskDevice | dev & deviceShares=filterMap 
-       (\s->s.identifier==ident)
-       (\s->{MTaskShare | s & value=val})
-       dev.deviceShares}
+getRealShare dev share = sdsFocus ()
+       $ mapReadWriteError (deviceLens dev share)
+       $ sdsFocus (Just (dev, share.identifier))
+       $ deviceStore
+
+deviceLens dev share = (mread, mwrite)
+where
+       mread :: [MTaskDevice] -> MaybeError TaskException BCValue
+       mread devs = case find ((==)dev) devs of
+               Nothing = Error $ exception "Device doesn't exist anymore"
+               Just {deviceShares} = case find ((==)share) deviceShares of
+                       Nothing = Error $ exception "Share doesn't exist anymore"
+                       Just share = Ok share.MTaskShare.value
+       
+       mwrite :: BCValue [MTaskDevice] -> MaybeError TaskException (Maybe [MTaskDevice])
+       mwrite val devs = case partition ((==)dev) devs of
+               ([], _) = Error $ exception "Device doesn't exist anymore"
+               ([_,_:_], _) = Error $ exception "Multiple matching devices"
+               ([d=:{deviceShares}], devs) = case partition ((==)share) deviceShares of
+                       ([], _) = Error $ exception "Share doesn't exist anymore"
+                       ([_,_:_], _) = Error $ exception "Multiple matching shares"
+                       ([s], shares)
+                               # s = {MTaskShare | s & value=val}
+                               # d = {MTaskDevice | d & deviceShares=[s:shares]}
+                               = Ok $ Just [d:devs]
+
+updateShareFromPublish :: MTaskDevice Int BCValue -> Task BCValue
+updateShareFromPublish dev ident val = set val 
+       $ mapReadWriteError (deviceLens dev dummy)
+       $ deviceStoreNP
+where
+       dummy = {MTaskShare|value=BCValue 0,identifier=ident,withTask=[]}