+The glue in the system is written in \gls{iTasks}. Functions for managing
+devices, \glspl{Task} and \glspl{SDS} are created. An interface is made that
+allows an interactive management console for the \gls{mTask} system. This
+interface provides functionality to list \glspl{SDS}, add \glspl{Task}, remove
+\glspl{Task}, administrate devices and view the state of the system.
+
\section{Integration}
+When the system starts up the devices residing in the \gls{SDS} must be cleaned
+up. It might be the case that they contain \glspl{Task}, \glspl{SDS} or errors.
+A user or programmer can then choose to reconnect some devices using the
+\CI{connectDevice} function.
+
+\begin{lstlisting}[caption={Starting up the devices},%
+ label={lst:startupdevs}]
+startupDevices :: Task [MTaskDevice]
+startupDevices = upd (map reset) deviceStoreNP
+ where reset d = {d & deviceTask=Nothing, deviceTasks=[], deviceError=Nothing}
+\end{lstlisting}
+
+An image of the management interface is shown in Figure~\ref{lst:manage}.
+The system management is done by a single \gls{Task} called \CI{mTaskManager}.
+To manage the system, a couple of different functionalities are needed and
+are launched. The left sidebar of the interface shows the list of example
+\glspl{Task} that are present in the system. When clicking a \gls{Task}, a
+dialog opens in which you can select the device to send the \gls{Task} to. The
+dialog might contain user specified variables. All example \glspl{mTask} are of
+the type \CI{Task (Main (ByteCode () Stmt))} and can thus ask for user input
+first.
+
+The bottom panel shows the device information. In this panel, the devices can
+be created and modified. Moreover, this panel allows the user to reconnect with
+a device after a restart of the server application.
+
+\begin{figure}[H]
+ \centering
+ \includegraphics[width=\linewidth]{manage}
+ \caption{The device management interface}\label{lst:management}
+\end{figure}
\section{Shares}
-\todo{Semantiek van shares, hoe ze in iTasks zijn, hoe typering}
+The architecture of the system stores the \glspl{SDS} in the \gls{SDS} that
+stores the list of devices. This means that if a \gls{SDS} updates, everyone
+watching it will be notified. This would result in to a lot of notifications
+that are not ment to be for the listener. Moreover, when a client updates the
+\gls{SDS} this is processed by the connection handler and results in an update
+of the real \gls{SDS}. When an \gls{iTasks}-\gls{Task} writes to a \gls{SDS}
+this is not passed on to the device.
+
+To solve the problem, parametric lenses are used on the device storage.
+Listing~\ref{lst:actualdev} shows the actual types for the device storage.
+Programmers wanting to access the entire \gls{SDS} use the \CI{deviceStoreNP}.
+Programmers wanting to access a single \gls{SDS} on a device can use the
+\CI{getRealShare} function which is a wrapper around the \CI{deviceStore} which
+applies a parametric lens to the \gls{SDS}.
+
+\begin{lstlisting}[label={lst:actualdev},%
+ caption={Real types for the device \gls{SDS}}]
+deviceStoreNP :: Shared [MTaskDevice]
+deviceStore :: RWShared (Maybe (MTaskDevice, Int)) [MTaskDevice] [MTaskDevice]
+
+realDeviceStore :: Shared [MTaskDevice]
+
+getRealShare :: MTaskDevice MTaskShare -> Shared BCValue
+\end{lstlisting}
+
+\subsection{Parametric Lens}
+The type of the parametric lens is \CI{Maybe (MTaskDevice, Int)} where the
+\CI{Int} is the identifier of the \gls{SDS}. The \gls{iTasks} way of applying
+lenses is through the \CI{sdsFocus} function and through the \CI{sdsLens}
+functions. \CI{sdsFocus} allows the programmer to fix the parameter.
+\CI{sdsLens} is basically a \CI{mapReadWrite} that has access to the parameter.
+This allows the programmer to create filters and lenses. Both of the methods
+are not good enough for the device \gls{SDS} because they do not achieve the
+writing to the actual device. Writing to a device requires being able to write
+to \glspl{SDS}. To solve this problem, a real base \gls{SDS} is created. All
+the details are visible in Listing~\ref{shareimpl}.
+\todo{elaborate}
+
+\begin{lstlisting}[label={lst:shareimpl},%
+ caption={Base share implementation}]
+realDeviceStore :: Shared [MTaskDevice]
+realDeviceStore = memoryShare "mTaskDevices" []
+
+deviceStore :: RWShared (Maybe (MTaskDevice, Int)) [MTaskDevice] [MTaskDevice]
+deviceStore = SDSSource {SDSSource | name="deviceStore", read=realRead, write=realWrite}
+where
+ realRead :: (Maybe (MTaskDevice,Int)) *IWorld -> (MaybeError TaskException [MTaskDevice], *IWorld)
+ realRead p iw = read realDeviceStore iw
+
+ realWrite :: (Maybe (MTaskDevice,Int)) [MTaskDevice] *IWorld
+ -> (MaybeError TaskException (SDSNotifyPred (Maybe (MTaskDevice,Int))), *IWorld)
+ realWrite mi w iw
+ # (merr, iw) = write w realDeviceStore iw
+ | isError merr || isNothing mi = (merr $> notifyPred mi, iw)
+ # (Just (dev, ident)) = mi
+ | ident == -1 = (merr $> notifyPred mi, iw)
+ = case find ((==)dev) w of
+ Nothing = (Error $ exception "Device doesn't exist anymore", iw)
+ Just {deviceShares} = case find (\d->d.identifier == ident) deviceShares of
+ Nothing = (Error $ exception $ "deviceStore: Share doesn't exist: " +++ toString ident, iw)
+ Just s = case sendMessagesIW [MTUpd ident s.MTaskShare.value] dev iw of
+ (Error e, iw) = (Error e, iw)
+ (Ok _, iw) = (Ok $ notifyPred mi, iw)
-\section{Lifting}
-\todo{Lift mTask taken naar echte taken, hoe werkt dat?}
+ notifyPred :: (Maybe (MTaskDevice, Int)) (Maybe (MTaskDevice, Int)) -> Bool
+ notifyPred Nothing Nothing = True
+ notifyPred Nothing (Just _) = False
+ notifyPred (Just _) Nothing = False
+ notifyPred (Just (d1, -1)) (Just (d2, _)) = d1 == d2
+ notifyPred (Just (d1, i1)) (Just (d2, i2)) = d1 == d2 && i1 == i2
+\end{lstlisting}
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