module AbstractGraphView where

{- Interface for graph viewing and abstraction.

It is possible to hide sets of nodes and edges.

Using a composition table for edge types,

paths through hidden nodes can be displayed.

Graphs, nodes, and edges are handled via

descriptors (here: integers), while node and

edge types are handled by user-supplied strings.

-}

import DaVinciGraph

import GraphDisp

import GraphConfigure

import Destructible

import List(nub)

import IORef

{- methods using fetch_graph return a quadruple containing the modified graph, a descriptor of the last modification (e.g. a new node), the descriptor that can be used for the next modification and a possible error message-}

-- Which graph display tool to be used, perhaps make it more tool independent?

instance Eq (DaVinciNode (String, Int, Int)) where

(==) = eq1

instance Eq (DaVinciArc (String, Int)) where

(==) = eq1

graphtool = daVinciSort

type OurGraph =

Graph DaVinciGraph

DaVinciGraphParms

DaVinciNode

DaVinciNodeType

DaVinciNodeTypeParms

DaVinciArc

DaVinciArcType

DaVinciArcTypeParms

-- Main datastructure for carrying around the graph,

-- both internally (nodes as integers), and at the daVinci level

type CompTable = [(String,String,String)]

data AbstractionGraph = AbstractionGraph {

theGraph :: OurGraph,

nodeTypes :: [(String,DaVinciNodeType (String,Int,Int))],

edgeTypes :: [(String,DaVinciArcType (String,Int))],

nodes :: [(Int,(String,DaVinciNode (String,Int,Int)))],

edges :: [(Int,(Int,Int,String,DaVinciArc (String,Int)))],

-- probably, also the abstracted graph needs to be stored,

-- and a list of hide/abstract events with the hidden nodes/edges (for each event),

-- which is used to restore things when showIt is called

edgeComp :: CompTable,

eventTable :: [(Int,Entry)]}

type Descr = Int

type GraphInfo = IORef ([(Descr,AbstractionGraph)],Descr) -- for each graph the descriptor and the graph,

-- plus a global counter for new descriptors

data Result = Result Descr -- graph, node or edge descriptor

(Maybe String) -- a possible error message

data Entry = Entry {newNodes :: [(Descr,(String,DaVinciNode (String,Int,Int)))],

oldNodes :: [(Descr,(String,String))],

newEdges :: [(Int,(Int,Int,String,DaVinciArc (String,Int)))],

oldEdges :: [(Int,(Int,Int,String,String))]

}

-- creates a new entry of the eventTable and fills it with the data contained in its parameters

createEntry :: [(Descr,(String,DaVinciNode (String,Int,Int)))] -> [(Descr,(String,String))] -> [(Descr,(Int,Int,String,DaVinciArc (String,Int)))] -> [(Descr,(Int,Int,String,String))] -> Descr -> (Int,Entry)

createEntry nn on ne oe cnt = (cnt, Entry {newNodes = nn, oldNodes = on, newEdges = ne, oldEdges = oe})

-- zips two lists by pairing each element of the first with each element of the second

specialzip :: [a] -> [b] -> [(a,b)]

specialzip [] _ = []

specialzip _ [] = []

specialzip (x:xs) (y:ys) = (x,y):(specialzip [x] ys)++(specialzip xs (y:ys))

-- similar to lookup, but also returns the decriptor

-- should only be used, if lookup will be successful (otherwise an error is thrown)

get :: Descr -> [(Descr,a)] -> (Descr,a)

get d list = case lookup d list of

Just r -> (d,r)

Nothing -> error ("get: descriptor unknown: "++(show d)++"\n"++(show (map fst list)))

-- lookup tables and failure handling

remove :: Eq a => a -> [(a,b)] -> [(a,b)]

remove x l = filter (\(y,_) -> not (x==y)) l

return_fail graphs msg =

return (Result 0 (Just msg))

-- lookup a graph descriptor and execute a command on the graph

-- the delete flag specifies if the graph should be removed from the graph list afterwards

-- fetch_graph :: Descr -> GraphInfo -> Bool -> a ?

fetch_graph gid gv delete cmd =

do (gs,ev_cnt) <- readIORef gv

case lookup gid gs of

Just g -> do (g',descr,ev_cnt',err) <- cmd (g,ev_cnt)

let gs'' = if delete then gs' else (gid,g'):gs'

writeIORef gv (gs'',ev_cnt')

return (Result descr err)

where gs' = remove gid gs

Nothing -> return (Result 0 (Just ("Graph id "++show gid++" not found")))

-- These are the operations of the interface

initgraphs :: IO GraphInfo

initgraphs = do newRef <- newIORef ([],0)

return newRef

makegraph :: String -> [GlobalMenu] ->

[(String,DaVinciNodeTypeParms (String,Descr,Descr))] ->

[(String,DaVinciArcTypeParms (String,Descr))] ->

CompTable -> GraphInfo -> IO Result

makegraph title menus nodetypeparams edgetypeparams comptable gv = do

(gs,ev_cnt) <- readIORef gv

let graphParms =

foldr ($$) (GraphTitle title $$

OptimiseLayout True $$

emptyGraphParms)

menus

abstractNodetypeparams = LocalMenu

(

Button "Unhide abstracted nodes" (

\ (name, descr, gid) -> do oldGv <- readIORef gv

(Result descr error) <- showIt gid descr gv

case error of

Just _ -> do writeIORef gv oldGv

return ()

Nothing -> do redisplay gid gv

return ()

)

) $$$

Rhombus $$$

ValueTitle ( \ (name,descr,gid) -> return name) $$$

emptyNodeTypeParms :: DaVinciNodeTypeParms (String,Int,Int)

(nodetypenames,nodetypeparams1) = unzip (("ABSTRACT",abstractNodetypeparams):nodetypeparams)

(edgetypenames,edgetypeparams1) = unzip edgetypeparams

graph <- GraphDisp.newGraph graphtool graphParms

nodetypes <- sequence (map (newNodeType graph) nodetypeparams1)

edgetypes <- sequence (map (newArcType graph) edgetypeparams1)

let g = AbstractionGraph {

theGraph = graph,

nodeTypes = zip nodetypenames nodetypes,

edgeTypes = zip edgetypenames edgetypes,

nodes = [],

edges = [],

edgeComp = comptable,

eventTable = [] }

writeIORef gv ((ev_cnt,g):gs,ev_cnt+1)

return (Result ev_cnt Nothing)

delgraph :: Descr -> GraphInfo -> IO Result

delgraph gid gv =

fetch_graph gid gv True

(\(g,ev_cnt) -> do destroy (theGraph g)

return (g,0,ev_cnt+1,Nothing))

delallgraphs :: GraphInfo -> IO ()

delallgraphs gv = do

(gs,ev_cnt) <- readIORef gv

destroy_all gs ev_cnt

where

destroy_all [] _ = return ()

destroy_all ((gid,_):gs) ev_cnt = do

writeIORef gv (gs,ev_cnt)

Result _ _ <- AbstractGraphView.delgraph gid gv

(_,ev_cnt') <- readIORef gv

destroy_all gs ev_cnt'

addnode :: Descr -> String -> String -> GraphInfo -> IO Result

addnode gid nodetype name gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

do case lookup nodetype (nodeTypes g) of

Nothing -> return (g,0,ev_cnt,Just ("addnode: illegal node type: "++nodetype))

Just nt ->

do existingNodesOfSameType <- sequence [(getNodeValue (theGraph g) davinciNode)|(descr,(tp,davinciNode)) <- (nodes g), tp == nodetype]

case elem name [existingName| (existingName, _,_) <- existingNodesOfSameType] of

_ -> do node <- newNode (theGraph g) nt (name,ev_cnt,gid)

return (g{nodes = (ev_cnt,(nodetype,node)):nodes g},ev_cnt,ev_cnt+1,Nothing)

True -> do return (g,0,ev_cnt, Just("addnode: node \"" ++ name ++ "\" of type " ++ nodetype ++ " already exists in graph " ++ (show gid)))

)

delnode :: Descr -> Descr -> GraphInfo -> IO Result

delnode gid node gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

case lookup node (nodes g) of

Just n -> do deleteNode (theGraph g) (snd n)

return (g{nodes = remove node (nodes g)},0,ev_cnt+1,Nothing)

Nothing -> return (g,0,ev_cnt,Just ("delnode: illegal node: "++show node))

)

{-

changenodetype

unclear how to implement, ask George

-}

addlink :: Descr -> String -> String -> Descr -> Descr -> GraphInfo -> IO Result

addlink gid edgetype name src tar gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

case (lookup edgetype (edgeTypes g),

lookup src (nodes g),

lookup tar (nodes g)) of

(Just et, Just src_node, Just tar_node) ->

do existingEdgesOfSameTypeAndPosition <- sequence [(getArcValue (theGraph g) davinciArc)|(descr,(srcId, tgtId, tp, davinciArc)) <- (edges g), tp == edgetype && srcId == src && tgtId == tar]

case lookup name existingEdgesOfSameTypeAndPosition of

_ ->

do edge <- newArc (theGraph g) et (name,ev_cnt) (snd src_node) (snd tar_node)

return (g{edges = (ev_cnt,(src,tar,edgetype,edge)):edges g},ev_cnt,ev_cnt+1,Nothing)

Just _ -> do srcToString <- getNodeNameAndTypeAsString g src

tarToString <- getNodeNameAndTypeAsString g tar

return (g,0,ev_cnt,Just("addlink: edge \""++name++"\" from node "++(show src)++(srcToString)++" to node "++(show tar)++(tarToString)++" of type "++edgetype++" already exists in graph "++(show gid)))

(Nothing,_,_) -> return (g,0,ev_cnt,Just ("addlink: illegal edge type: "++edgetype))

(_,Nothing,_) -> return (g,0,ev_cnt,Just ("addlink: illegal source node id: "++show src))

(_,_,Nothing) -> return (g,0,ev_cnt,Just ("addlink: illegal target node id: "++show tar))

)

getNodeNameAndTypeAsString :: AbstractionGraph -> Descr -> IO String

getNodeNameAndTypeAsString g descr = case lookup descr (nodes g) of

Just (tp, davinciNode) ->

do (name, i, j) <- getNodeValue (theGraph g) davinciNode

return (" (\""++name++"\" of type "++tp++")")

Nothing -> error ("getNodeNameAndTypeAsString: unknown node: "++(show descr))

dellink :: Descr -> Descr -> GraphInfo -> IO Result

dellink gid edge gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

case lookup edge (edges g) of

Just (_,_,_,e) ->

do deleteArc (theGraph g) e

return (g{edges = remove edge (edges g)},0,ev_cnt+1,Nothing)

Nothing -> return (g,0,ev_cnt,Just ("dellink: illegal edge: "++show edge))

)

redisplay :: Descr -> GraphInfo -> IO Result

redisplay gid gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

do redraw (theGraph g)

return (g,0,ev_cnt+1,Nothing)

)

-- determines from the types of two edges the type of the path replacing them (using the edgeComp table of the graph)

determineedgetype :: AbstractionGraph -> (String,String) -> Maybe String

determineedgetype g (t1,t2) = case result of

[] -> Nothing

x:xs -> Just x

where result = [t| (tp1,tp2,t) <- (edgeComp g), (tp1==t1)&&(tp2==t2)]

-- returns a pair of lists: one list of all in- and one of all out-going edges of the node

fetchEdgesOfNode :: AbstractionGraph -> Descr -> Maybe ([Descr],[Descr])

fetchEdgesOfNode g node = case sequence (map ((flip lookup) (edges g)) (map fst (edges g))) of

Just el -> Just ([descr|ed@(descr,(_,t,_,_)) <- (edges g), t == node],[descr|ed@(descr,(s,_,_,_)) <- (edges g), s == node])

Nothing -> Nothing

hidenodes :: Descr -> [Descr] -> GraphInfo -> IO Result

hidenodes gid node_list gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

case sequence (map (\node -> lookup node (nodes g)) node_list) of

Just nl -> do -- try to determine the path to add and the edges to remove

case makepathsMain g node_list of

-- try to create the paths

Just (newEdges,delEdges) -> do -- save the old edges...

let oeDescr = nub ((concat (map fst delEdges))++(concat (map snd delEdges)))

oe = map (\ed -> get ed (edges g)) oeDescr

oldEdges <- saveOldEdges g oe

-- ... then try to remove them from the graph

(gs,_) <- readIORef gv

writeIORef gv (gs,ev_cnt+1)

deletedEdges@(Result de1 error1) <- hideedgesaux gid oeDescr gv

info1 <- readIORef gv

case error1 of

Nothing -> do -- determine the _new_ edges...

let existingEdges = [(src,tgt,tp)|(descr,(src,tgt,tp,daVinci)) <- (edges (snd (get gid (fst info1))))]

filteredNewEdges = [path| path@(src,tgt,tp) <- newEdges, notElem (src,tgt,tp) existingEdges]

-- ... and try to add them

paths@(Result de2 error2) <- addpaths gid filteredNewEdges gv --info1

case error2 of

Nothing -> do -- save the old nodes...

let on = map (\nd -> get nd (nodes g)) node_list

oldNodes <- saveOldNodes g on

-- ... then try to remove them from the graph

deletedNodes@(Result de3 error3) <- hidenodesaux gid node_list gv --info2

info3 <- readIORef gv

case error3 of

Nothing -> do -- save the changes in an entry

let g' = snd (get gid (fst info3))

newEdges = [edge| edge <- (edges g'), notElem edge (edges g)]

newEvent = createEntry [] oldNodes newEdges oldEdges ev_cnt

return (g'{eventTable = newEvent:eventTable g'},ev_cnt,(snd info3)+1,Nothing)

Just t -> return (g,0,ev_cnt,Just ("hidenodes: error hiding nodes: "++t))

Just text -> return (g,0,ev_cnt,Just ("hidenodes: error adding paths: "++text))

Just text -> return (g,0,ev_cnt,Just ("hidenodes: error deleting edges: "++text))

Nothing -> return (g,0,ev_cnt,Just "hidenodes: error making paths\n(possible reasons: an error occured getting the edges of the nodes\nor a pathtype could not be determined (missing entry in edgeComp table))")

Nothing -> return (g,0,ev_cnt,Just "hidenodes: unknown node(s)")

)

-- auxiliary function, which removes the nodes from the graph

hidenodesaux :: Descr -> [Descr] -> GraphInfo -> IO Result

hidenodesaux gid [] gv = do (gs,ev_cnt) <- readIORef gv

return (Result ev_cnt Nothing)

hidenodesaux gid (d:delNodes) gv = do deletedNode@(Result de error) <- delnode gid d gv

case error of

Nothing -> do hidenodesaux gid delNodes gv

Just t -> return deletedNode

-- returns the paths to add and the edges to remove

makepathsMain :: AbstractionGraph -> [Descr] -> Maybe ([(Descr,Descr,String)],[([Descr],[Descr])])

makepathsMain g node_list =

-- try to determine the in- and outgoing edges of the nodes

case sequence (map (fetchEdgesOfNode g) node_list) of

-- try to make paths of these edges

Just edgelistPairs -> case sequence (map (makepaths g node_list) edgelistPairs) of

-- return the paths to add and the edges to remove

Just paths -> Just (nub (concat paths),edgelistPairs)

Nothing -> Nothing

Nothing -> Nothing

-- returns a list of paths (ie source, target and type) to be added

makepaths :: AbstractionGraph -> [Descr] -> ([Descr],[Descr]) -> Maybe [(Descr,Descr,String)]

makepaths g node_list (inEdges,outEdges) =

-- try to lookup the edges of the node

case (sequence (map (\ed -> lookup ed (edges g)) inEdges),sequence (map (\ed -> lookup ed (edges g)) outEdges)) of

(Just ie, Just oe) ->

-- try to make paths out of them

case sequence (map (makepathsaux g node_list []) (specialzip ie oe)) of

-- return the paths

Just paths -> Just (concat paths)

Nothing -> Nothing

(Nothing,_) -> Nothing

(_,Nothing) -> Nothing

-- determines source, target and type of the path to be added and checks it using method checkpath

makepathsaux :: AbstractionGraph -> [Descr] -> [Descr] -> ((Descr,Descr,String,DaVinciArc(String,Int)),(Descr,Descr,String,DaVinciArc(String,Int))) -> Maybe [(Descr,Descr,String)]

makepathsaux g node_list alreadyPassedNodes ((s1,t1,ty1,ed1),(s2,t2,ty2,ed2)) =

-- try to determine the type of the path

case determineedgetype g (ty1,ty2) of

-- return the checked path

Just ty -> checkpath g node_list alreadyPassedNodes (s1,t2,ty,ed1) -- ed1 is just a dummy value (Dummiewert)

Nothing -> Nothing

-- check, if the source or the target of an edge are element of the list of nodes that are to be hidden

-- if so, find out the "next" sources/targets and check again

-- remember which nodes have been passed to avoid infinite loops

checkpath :: AbstractionGraph -> [Descr] -> [Descr] -> (Descr,Descr,String,DaVinciArc(String,Int)) -> Maybe [(Descr,Descr,String)]

checkpath g node_list alreadyPassedNodes path@(src,tgt,ty,ed)

| elem src alreadyPassedNodes || elem tgt alreadyPassedNodes = Just []

| elem src node_list = -- try to determine the in- and outgoing edges of the source node

case fetchEdgesOfNode g src of

-- try to lookup ingoing edges

Just (inEdges,outEdges) -> case sequence (map (\ed -> lookup ed (edges g)) inEdges) of

-- try to make paths of these edges and the "tail" of the path (and recursively check them)

Just el -> case sequence (map (makepathsaux g node_list (src:alreadyPassedNodes)) (specialzip el [path])) of

Just p -> Just (concat p)

Nothing -> Nothing

Nothing -> Nothing

| elem tgt node_list = -- try to determine the in- and outgoing edges of the target node

case fetchEdgesOfNode g tgt of

-- try to lookup the outgoing edges

Just (inEdges,outEdges) -> case sequence (map (\ed -> lookup ed (edges g)) outEdges) of

-- try to make paths of these edges and the "init" of the path (and recursively check them)

Just el -> case sequence (map (makepathsaux g node_list (tgt:alreadyPassedNodes)) (specialzip [path] el)) of

Just p -> Just (concat p)

Nothing -> Nothing

Nothing -> Nothing

Nothing -> Nothing

| otherwise = -- nothing to be done

Just [(src,tgt,ty)]

-- adds the paths (given source, target and type)

addpaths :: Descr -> [(Descr,Descr,String)] -> GraphInfo -> IO Result

addpaths gid [] gv = do (gs,ev_cnt) <- readIORef gv

return (Result ev_cnt Nothing)

addpaths gid ((src,tgt,ty):newEdges) gv = do edge@(Result de error) <- addlink gid ty "" src tgt gv

case error of

Nothing -> do addpaths gid newEdges gv

Just t -> return edge

-- fetches all the nodes of the given type and hides them using hidenodes

hidenodetype :: Descr -> String -> GraphInfo -> IO Result

hidenodetype gid nodetype gv = fetch_graph gid gv False (\(g,ev_cnt) ->

-- check if the node type is valid

do case lookup nodetype (nodeTypes g) of

Just nt ->

do let nodelist = [descr|(descr,(tp,_)) <- (nodes g), tp == nodetype]

case nodelist of

[] -> do return (g,0,ev_cnt,Just ("hidenodetype: no nodes of type "++nodetype++" found in graph "++(show gid)))

node_list -> do (Result de error) <- hidenodes gid nodelist gv

info <- readIORef gv

return (snd (get gid (fst info)), de, (snd info), error)

Nothing -> return (g,0,ev_cnt,Just ("hidenodetype: illegal node type: "++nodetype))

)

-- like hidenodes, but replaces the hidden nodes by a new node

-- with a menu to unhide the nodes (not yet implemented)

abstractnodes :: Descr -> [Descr] -> GraphInfo -> IO Result

abstractnodes gid [] gv = fetch_graph gid gv False (\(g,ev_cnt) -> return (g,0,ev_cnt,Nothing))

abstractnodes gid node_list gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

-- try to lookup the nodes of the list

case sequence (map (\nd -> lookup nd (nodes g)) node_list) of

Just nl -> -- try to lookup the in- and outgoing edges of the nodes

case sequence (map (fetchEdgesOfNode g) node_list) of

Just el -> do -- save the old edges

let oeDescr = nub ((concat (map fst el))++(concat (map snd el)))

oe = map (\edge -> get edge (edges g)) oeDescr

oldEdges <- saveOldEdges g oe

-- save the old nodes

let on = map (\node -> get node (nodes g)) node_list

oldNodes <- saveOldNodes g on

-- try to create the new abstract node and add its in- and outgoing paths

(Result de1 error1) <- replaceByAbstractNode gid node_list nl oeDescr gv --(gs,ev_cnt+1)

case error1 of

Nothing -> do -- try to remove the in- and outgoing edges of the nodes to be hidden

(Result de2 error2) <- hideedgesaux gid oeDescr gv

case error2 of

Nothing -> do -- try to remove the nodes of the list

(Result de3 error3) <- hidenodesaux gid node_list gv --info2

info3 <- readIORef gv

case error3 of

Nothing -> do -- save the changes in an entry

let g' = snd (get gid (fst info3))

newNodes = [nd| nd <- nodes g', notElem nd (nodes g)]

newEdges = [ed| ed <- edges g', notElem ed (edges g)]

newEntry = createEntry newNodes oldNodes newEdges oldEdges ev_cnt

return (g'{eventTable=newEntry:eventTable g'},ev_cnt,snd info3,Nothing)

Just t -> return (g,0,ev_cnt,Just ("abstractnodes: error hiding nodes: "++t))

Just t -> return (g,0,ev_cnt,Just ("abstractnodes: error hiding edges: " ++ t))

Just t -> return (g,0,ev_cnt,Just ("abstractnodes: error making abstract node: "++ t))

Nothing -> return (g,0,ev_cnt,Just "abstractnodes: error fetching the edges of the nodes")

Nothing -> return (g,0,ev_cnt,Just "abstractnodes: unknown nodes")

)

-- adds an abstract node, determines and adds its in- and outgoing paths

replaceByAbstractNode :: Descr -> [Descr] -> [(String,DaVinciNode(String,Int,Int))] -> [Descr] -> GraphInfo -> IO Result

replaceByAbstractNode gid node_list nl edge_list gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

-- try to lookup the in- and outgoing edges of the nodes that are to be hidden

case sequence (map (\ed -> lookup ed (edges g)) edge_list) of

Just el -> do -- try to add an abstract node

(Result de1 error1) <- addnode gid "ABSTRACT" (show ev_cnt) gv

case error1 of

Nothing -> do -- determine its in- and outgoing paths...

let newEdges = [(src,de1,tp)| (src,tgt,tp,_) <- el, ((notElem src node_list) && (elem tgt node_list))]

++ [(de1,tgt,tp)| (src,tgt,tp,_) <- el, ((elem src node_list) && (notElem tgt node_list))]

-- ... and try to add them

(Result de2 error2) <- addpaths gid (nub newEdges) gv

info2 <- readIORef gv

case error2 of

Nothing -> do -- return the modified graph

let g' = snd (get gid (fst info2))

return (g',de2,snd info2,Nothing)

Just t -> return (g,0,ev_cnt,error2)

Just text -> return (g,0,ev_cnt,Just ("replaceByAbstractNode: error creating abstract node: "++text))

Nothing -> return (g,0,ev_cnt,Just "replaceByAbstractNode: error looking up the edges of the nodes")

)

hideedges :: Descr -> [Descr] -> GraphInfo -> IO Result

hideedges gid edge_list gv = fetch_graph gid gv False (\(g,ev_cnt) ->

-- check if all of the edges exist

case sequence (map (\edge -> lookup edge (edges g)) edge_list) of

Just el -> do -- save the old edges ...

let oe = map (\edge -> get edge (edges g)) edge_list

oldEdges <- saveOldEdges g oe

-- ... then try to remove them from the graph

(gs,_) <- readIORef gv

writeIORef gv (gs,ev_cnt+1)

(Result de error) <- hideedgesaux gid edge_list gv

info <- readIORef gv

case error of

Nothing -> do -- save the changes in an entry

let g' = snd (get gid (fst info))

newEntry = createEntry [] [] [] oldEdges ev_cnt

return (g'{eventTable = newEntry:eventTable g'},ev_cnt,snd info,Nothing)

Just text -> return (g,0,ev_cnt,Just ("hideedges: error hiding edges: "++text))

Nothing -> return (g,0,ev_cnt,Just "hideedges: unknown edges")

)

-- an auxiliary function, which removes the edges from the graph

hideedgesaux :: Descr -> [Descr] -> GraphInfo -> IO Result

hideedgesaux gid [] gv = do (gs,ev_cnt) <- readIORef gv

return (Result ev_cnt Nothing)

hideedgesaux gid (d:delEdges) gv = do dle@(Result descr error) <- dellink gid d gv

case error of

Nothing -> do hideedgesaux gid delEdges gv --info

Just t -> return dle

-- fetches all the edges of the given type and hides them using hideedges

hideedgetype :: Descr -> String -> GraphInfo -> IO Result

hideedgetype gid edgetype gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

-- check if the edge type is valid

case lookup edgetype (edgeTypes g) of

Just et -> do let edgelist = [descr|(descr,(_,_,tp,_)) <- (edges g), tp == edgetype]

case edgelist of

[] -> do return (g,0,ev_cnt,Just ("hideedgetype: no edges of type "++edgetype++" found in graph "++(show gid)))

edge_list -> do (Result de error) <- hideedges gid edge_list gv

info <- readIORef gv

return (snd (get gid (fst info)), de, snd info,error)

Nothing -> return (g,0,ev_cnt,Just ("hideedgetype: illegal edge type: "++edgetype))

)

-- function to undo hide-events

showIt :: Descr -> Descr -> GraphInfo -> IO Result

showIt gid hide_event gv =

fetch_graph gid gv False (\(g,ev_cnt) ->

-- try to lookup the hide-event

case lookup hide_event (eventTable g) of

Just entry -> do -- try to remove the paths that had been added

(Result de1 error1) <- hideedgesaux gid (map fst (newEdges entry)) gv

case error1 of

Nothing -> do -- try to add the nodes that had been hidden

(Result de2 error2) <- shownodes gid (oldNodes entry) gv

case error2 of

Nothing -> do -- try to remove the nodes that had been added

(Result de3 error3) <- hidenodesaux gid (map fst (newNodes entry)) gv

case error3 of

Nothing -> do -- try to add the edges that had been hidden

(Result de4 error4) <- showedges gid (oldEdges entry) gv

info4 <- readIORef gv

case error4 of

Nothing -> do -- remove the event from the eventTable

let g' = snd (get gid (fst info4))

return (g'{eventTable = remove hide_event (eventTable g')},0,ev_cnt+1,Nothing)

Just t4 -> return (g,0,ev_cnt,Just ("showIt: error restoring old edges:\n-> "++t4))

Just t3 -> return (g,0,ev_cnt,Just ("showIt: error removing nodes:\n-> "++t3))

Just t2 -> return (g,0,ev_cnt,Just ("showIt: error restoring nodes:\n-> "++t2))

Just t1 -> return (g,0,ev_cnt,Just ("showIt: error removing edges:\n-> "++t1))

Nothing -> return (g,0,ev_cnt,Just ("showIt: invalid event descriptor: "++(show hide_event)))

)

-- adds nodes that had been hidden

shownodes :: Descr -> [(Descr,(String,String))] -> GraphInfo -> IO Result

shownodes gid [] gv = do (gs,ev_cnt) <- readIORef gv

return (Result ev_cnt Nothing)

shownodes gid ((node@(d,(tp,name))):list) gv =

do (gs,_) <- readIORef gv

let g = snd (get gid gs)

-- try to add the first node

writeIORef gv (gs,d)

nd@(Result de error) <- addnode gid tp name gv

case error of

Nothing -> do -- try to add the rest

shownodes gid list gv

Just _ -> return nd

-- adds edges that had been hidden

showedges :: Descr -> [(Int,(Int,Int,String,String))] -> GraphInfo -> IO Result

showedges gid [] gv = do (gs,ev_cnt) <- readIORef gv

return (Result ev_cnt Nothing)

showedges gid ((edge@(d,(src,tgt,tp,davinciarc))):list) gv =

do (gs,_) <- readIORef gv

let g = snd (get gid gs)

-- try to add the first edge

writeIORef gv (gs,d)

ed@(Result de err) <- addlink gid tp davinciarc src tgt gv

case err of

Nothing -> do -- try to add the rest

showedges gid list gv

Just _ -> return ed

-- creates a list of the nodes that will be hidden (ie descriptor,type and name)

saveOldNodes :: AbstractionGraph -> [(Int,(String,DaVinciNode(String,Int,Int)))] -> IO [(Int,(String,String))]

saveOldNodes g [] = return []

saveOldNodes g ((node@(de,(tp,davincinode))):list) = do (name,descr,gid) <- getNodeValue (theGraph g) davincinode

restOfList <- saveOldNodes g list

return ((de,(tp,name)):restOfList)

-- creates a list of the edges that will be hidden (ie descriptor,source,target,type and name)

saveOldEdges :: AbstractionGraph -> [(Int,(Int,Int,String,DaVinciArc(String,Int)))] -> IO [(Int,(Int,Int,String,String))]

saveOldEdges g [] = return []

saveOldEdges g (edge@(de,(src,tgt,tp,davinciarc)):list) = do value <- getArcValue (theGraph g) davinciarc

restOfList <- saveOldEdges g list

return ((de,(src,tgt,tp,(fst value))):restOfList)