{-# LANGUAGE MultiParamTypeClasses , FlexibleInstances #-} {- | Module : Data.GraphViz.Types Description : Definition of the Graphviz types. Copyright : (c) Matthew Sackman, Ivan Lazar Miljenovic License : 3-Clause BSD-style Maintainer : Ivan.Miljenovic@gmail.com This module defines the overall types and methods that interact with them for the Graphviz library. The specifications are based loosely upon the information available at: Printing of /Dot/ code is done as strictly as possible, whilst parsing is as permissive as possible. For example, if the types allow it then @\"2\"@ will be parsed as an 'Int' value. Note that quoting and escaping of 'String' values is done automagically. A summary of known limitations\/differences: * When creating 'GraphID' values for 'graphID' and 'subGraphID', you should ensure that none of them have the same printed value as one of the 'nodeID' values to avoid any possible problems. * If you want any 'GlobalAttributes' in a 'DotSubGraph' and want them to only apply to that 'DotSubGraph', then you must ensure it does indeed have a valid 'GraphID'. * All 'DotSubGraph's with @'isCluster' = 'True'@ /must/ have unique 'subGraphID' values (well, only if you want them to be generated sensibly). * If eventually outputting to a format such as SVG, then you should make sure that your 'DotGraph' has a 'graphID', as that is used as the title of the resulting image. * Whilst 'DotGraph', etc. are polymorphic in their node type, you should ensure that you use a relatively simple node type (that is, it only covers a single line, etc.). * Also, whilst Graphviz allows you to mix the types used for nodes, this library requires\/assumes that they are all the same type. * 'DotEdge' defines an edge @(a, b)@ (with an edge going from @a@ to @b@); in /Dot/ parlance the edge has a head at @a@ and a tail at @b@. Care must be taken when using the related @Head*@ and @Tail*@ 'Attribute's. See the differences section in "Data.GraphViz.Attributes" for more information. * It is common to see multiple edges defined on the one line in Dot (e.g. @n1 -> n2 -> n3@ means to create a directed edge from @n1@ to @n2@ and from @n2@ to @n3@). These types of edge definitions are parseable; however, they are converted to singleton edges. * Cannot create edges with subgraphs\/clusters as one of the end points. * When either creating a 'DotGraph' by hand or parsing one, it is possible to specify that @'directedGraph' = d@, but 'DotEdge' values with @'directedEdge' = 'not' d@. * Nodes cannot have Port values. * Cannot place items in an arbitrary order: in particular, this means that it is not possible to use the normal Graphviz hack of having graph attributes that do not apply to subgraphs\/clusters by listing them /after/ the subgraphs\/clusters. If you wish to be able to use an arbitrary ordering, you may wish to use "Data.GraphViz.Types.Generalised". * The parser will strip out comments and convert multiline strings into a single line string. Pre-processor lines (i.e. those started by @#@) and string concatenation are not yet supported. See "Data.GraphViz.Attributes" for more limitations. -} module Data.GraphViz.Types ( -- * Abstraction from the representation type DotRepr(..) -- ** Printing and parsing a @DotRepr@. , printDotGraph , parseDotGraph -- * The overall representation of a graph in /Dot/ format. , DotGraph(..) -- ** Reporting of errors in a @DotGraph@. , DotError(..) , isValidGraph , graphErrors -- * Sub-components of a @DotGraph@. , GraphID(..) , DotStatements(..) , GlobalAttributes(..) , DotSubGraph(..) , DotNode(..) , DotEdge(..) ) where import Data.GraphViz.Types.Common import Data.GraphViz.Attributes import Data.GraphViz.Util import Data.GraphViz.Parsing import Data.GraphViz.Printing import Control.Monad(liftM) -- ----------------------------------------------------------------------------- -- | This class is used to provide a common interface to different -- ways of representing a graph in /Dot/ form. class (PrintDot (dg n), ParseDot (dg n)) => DotRepr dg n where -- | Is this graph directed? graphIsDirected :: dg n -> Bool -- | A strict graph disallows multiple edges. makeStrict :: dg n -> dg n -- | Set the ID of the graph. setID :: GraphID -> dg n -> dg n -- | Return all the 'DotNode's contained within this 'DotRepr'. -- There is no requirement for it to return implicitly defined -- nodes found only within a 'DotEdge'. graphNodes :: dg n -> [DotNode n] -- | Return all the 'DotEdge's contained within this 'DotRepr'. graphEdges :: dg n -> [DotEdge n] -- | The actual /Dot/ code for an instance of 'DotRepr'. Note that it -- is expected that @'parseDotGraph' . 'printDotGraph' == 'id'@ -- (this might not be true the other way around due to un-parseable -- components). printDotGraph :: (DotRepr dg n) => dg n -> String printDotGraph = printIt -- | Parse a limited subset of the Dot language to form an instance of -- 'DotRepr'. Each instance may have its own limitations on what -- may or may not be parseable Dot code. -- -- Also removes any comments, etc. before parsing. parseDotGraph :: (DotRepr dg n) => String -> dg n parseDotGraph = fst . parseIt . preProcess -- ----------------------------------------------------------------------------- -- | The internal representation of a graph in Dot form. data DotGraph a = DotGraph { strictGraph :: Bool -- ^ If 'True', no multiple edges are drawn. , directedGraph :: Bool , graphID :: Maybe GraphID , graphStatements :: DotStatements a } deriving (Eq, Ord, Show, Read) instance (PrintDot n, ParseDot n) => DotRepr DotGraph n where graphIsDirected = directedGraph makeStrict g = g { strictGraph = True } setID i g = g { graphID = Just i } graphNodes = statementNodes . graphStatements graphEdges = statementEdges . graphStatements -- | Check if all the 'Attribute's are being used correctly. isValidGraph :: DotGraph a -> Bool isValidGraph = null . graphErrors -- | Return detectable errors in the 'DotGraph'. graphErrors :: DotGraph a -> [DotError a] graphErrors = invalidStmts usedByGraphs . graphStatements instance (PrintDot a) => PrintDot (DotGraph a) where unqtDot = printStmtBased printGraphID' graphStatements toDot where printGraphID' = printGraphID strictGraph directedGraph graphID instance (ParseDot a) => ParseDot (DotGraph a) where parseUnqt = parseStmtBased parse (parseGraphID DotGraph) parse = parseUnqt -- Don't want the option of quoting `adjustErr` (++ "\n\nNot a valid DotGraph") instance Functor DotGraph where fmap f g = g { graphStatements = fmap f $ graphStatements g } -- ----------------------------------------------------------------------------- -- | Used to record invalid 'Attribute' usage. A 'Just' value denotes -- that it was used in an explicit 'DotNode' or 'DotEdge' usage; -- 'Nothing' means that it was used in a 'GlobalAttributes' value. data DotError a = GraphError Attribute | NodeError (Maybe a) Attribute | EdgeError (Maybe (a,a)) Attribute deriving (Eq, Ord, Show, Read) -- ----------------------------------------------------------------------------- data DotStatements a = DotStmts { attrStmts :: [GlobalAttributes] , subGraphs :: [DotSubGraph a] , nodeStmts :: [DotNode a] , edgeStmts :: [DotEdge a] } deriving (Eq, Ord, Show, Read) instance (PrintDot a) => PrintDot (DotStatements a) where unqtDot stmts = vcat [ unqtDot $ attrStmts stmts , unqtDot $ subGraphs stmts , unqtDot $ nodeStmts stmts , unqtDot $ edgeStmts stmts ] instance (ParseDot a) => ParseDot (DotStatements a) where parseUnqt = do atts <- tryParseList newline' sGraphs <- tryParseList newline' nodes <- tryParseList newline' edges <- tryParseList return $ DotStmts atts sGraphs nodes edges parse = parseUnqt -- Don't want the option of quoting `adjustErr` (++ "Not a valid set of statements") instance Functor DotStatements where fmap f stmts = stmts { subGraphs = map (fmap f) $ subGraphs stmts , nodeStmts = map (fmap f) $ nodeStmts stmts , edgeStmts = map (fmap f) $ edgeStmts stmts } -- | The function represents which function to use to check the -- 'GraphAttrs' values. invalidStmts :: (Attribute -> Bool) -> DotStatements a -> [DotError a] invalidStmts f stmts = concatMap (invalidGlobal f) (attrStmts stmts) ++ concatMap invalidSubGraph (subGraphs stmts) ++ concatMap invalidNode (nodeStmts stmts) ++ concatMap invalidEdge (edgeStmts stmts) statementNodes :: DotStatements a -> [DotNode a] statementNodes stmts = concatMap subGraphNodes (subGraphs stmts) ++ nodeStmts stmts statementEdges :: DotStatements a -> [DotEdge a] statementEdges stmts = concatMap subGraphEdges (subGraphs stmts) ++ edgeStmts stmts -- ----------------------------------------------------------------------------- -- | Represents a list of top-level list of 'Attribute's for the -- entire graph/sub-graph. Note that 'GraphAttrs' also applies to -- 'DotSubGraph's. -- -- Note that Dot allows a single 'Attribute' to be listen on a line; -- if this is the case then when parsing, the type of 'Attribute' it -- is determined and that type of 'GlobalAttribute' is created. data GlobalAttributes = GraphAttrs { attrs :: Attributes } | NodeAttrs { attrs :: Attributes } | EdgeAttrs { attrs :: Attributes } deriving (Eq, Ord, Show, Read) instance PrintDot GlobalAttributes where unqtDot = printAttrBased printGlobAttrType attrs unqtListToDot = printAttrBasedList printGlobAttrType attrs listToDot = unqtListToDot printGlobAttrType :: GlobalAttributes -> DotCode printGlobAttrType GraphAttrs{} = text "graph" printGlobAttrType NodeAttrs{} = text "node" printGlobAttrType EdgeAttrs{} = text "edge" instance ParseDot GlobalAttributes where parseUnqt = parseAttrBased parseGlobAttrType `onFail` liftM determineType parse `discard` optional lineEnd parse = parseUnqt -- Don't want the option of quoting `adjustErr` (++ "\n\nNot a valid listing of global attributes") -- Have to do this manually because of the special case parseUnqtList = sepBy (whitespace' >> parse) newline' parseList = parseUnqtList parseGlobAttrType :: Parse (Attributes -> GlobalAttributes) parseGlobAttrType = oneOf [ stringRep GraphAttrs "graph" , stringRep NodeAttrs "node" , stringRep EdgeAttrs "edge" ] determineType :: Attribute -> GlobalAttributes determineType attr | usedByGraphs attr = GraphAttrs attr' | usedByClusters attr = GraphAttrs attr' -- Also covers SubGraph case | usedByNodes attr = NodeAttrs attr' | otherwise = EdgeAttrs attr' -- Must be for edges. where attr' = [attr] invalidGlobal :: (Attribute -> Bool) -> GlobalAttributes -> [DotError a] invalidGlobal f (GraphAttrs as) = map GraphError $ filter (not . f) as invalidGlobal _ (NodeAttrs as) = map (NodeError Nothing) $ filter (not . usedByNodes) as invalidGlobal _ (EdgeAttrs as) = map (EdgeError Nothing) $ filter (not . usedByEdges) as -- ----------------------------------------------------------------------------- data DotSubGraph a = DotSG { isCluster :: Bool , subGraphID :: Maybe GraphID , subGraphStmts :: DotStatements a } deriving (Eq, Ord, Show, Read) instance (PrintDot a) => PrintDot (DotSubGraph a) where unqtDot = printStmtBased printSubGraphID' subGraphStmts toDot unqtListToDot = printStmtBasedList printSubGraphID' subGraphStmts toDot listToDot = unqtListToDot printSubGraphID' :: DotSubGraph a -> DotCode printSubGraphID' = printSubGraphID (\sg -> (isCluster sg, subGraphID sg)) instance (ParseDot a) => ParseDot (DotSubGraph a) where parseUnqt = parseStmtBased parseUnqt (parseSubGraphID DotSG) parse = parseUnqt -- Don't want the option of quoting `adjustErr` (++ "\n\nNot a valid Sub Graph") parseUnqtList = parseStmtBasedList parseUnqt (parseSubGraphID DotSG) parseList = parseUnqtList instance Functor DotSubGraph where fmap f sg = sg { subGraphStmts = fmap f $ subGraphStmts sg } invalidSubGraph :: DotSubGraph a -> [DotError a] invalidSubGraph sg = invalidStmts valFunc (subGraphStmts sg) where valFunc = bool usedBySubGraphs usedByClusters (isCluster sg) subGraphNodes :: DotSubGraph a -> [DotNode a] subGraphNodes = statementNodes . subGraphStmts subGraphEdges :: DotSubGraph a -> [DotEdge a] subGraphEdges = statementEdges . subGraphStmts -- ----------------------------------------------------------------------------- -- | A node in 'DotGraph'. data DotNode a = DotNode { nodeID :: a , nodeAttributes :: Attributes } deriving (Eq, Ord, Show, Read) instance (PrintDot a) => PrintDot (DotNode a) where unqtDot = printAttrBased printNodeID nodeAttributes unqtListToDot = printAttrBasedList printNodeID nodeAttributes listToDot = unqtListToDot printNodeID :: (PrintDot a) => DotNode a -> DotCode printNodeID = toDot . nodeID instance (ParseDot a) => ParseDot (DotNode a) where parseUnqt = parseAttrBased parseNodeID parse = parseUnqt -- Don't want the option of quoting parseUnqtList = parseAttrBasedList parseNodeID parseList = parseUnqtList parseNodeID :: (ParseDot a) => Parse (Attributes -> DotNode a) parseNodeID = liftM DotNode parse instance Functor DotNode where fmap f n = n { nodeID = f $ nodeID n } invalidNode :: DotNode a -> [DotError a] invalidNode n = map (NodeError (Just $ nodeID n)) $ filter (not . usedByNodes) (nodeAttributes n) -- ----------------------------------------------------------------------------- -- | An edge in 'DotGraph'. data DotEdge a = DotEdge { edgeFromNodeID :: a , edgeToNodeID :: a , directedEdge :: Bool , edgeAttributes :: Attributes } deriving (Eq, Ord, Show, Read) instance (PrintDot a) => PrintDot (DotEdge a) where unqtDot = printAttrBased printEdgeID edgeAttributes unqtListToDot = printAttrBasedList printEdgeID edgeAttributes listToDot = unqtListToDot printEdgeID :: (PrintDot a) => DotEdge a -> DotCode printEdgeID e = unqtDot (edgeFromNodeID e) <+> bool undirEdge' dirEdge' (directedEdge e) <+> unqtDot (edgeToNodeID e) instance (ParseDot a) => ParseDot (DotEdge a) where parseUnqt = parseAttrBased parseEdgeID parse = parseUnqt -- Don't want the option of quoting -- Have to take into account edges of the type "n1 -> n2 -> n3", etc. parseUnqtList = liftM concat $ sepBy (whitespace' >> parseEdgeLine) newline' parseList = parseUnqtList parseEdgeID :: (ParseDot a) => Parse (Attributes -> DotEdge a) parseEdgeID = do eHead <- parse whitespace' eType <- parseEdgeType whitespace' eTail <- parse return $ DotEdge eHead eTail eType parseEdgeType :: Parse Bool parseEdgeType = stringRep True dirEdge `onFail` stringRep False undirEdge parseEdgeLine :: (ParseDot a) => Parse [DotEdge a] parseEdgeLine = liftM return parse `onFail` do n1 <- parse ens <- many1 $ do whitespace' eType <- parseEdgeType whitespace' n <- parse return (eType, n) let ens' = (True, n1) : ens efs = zipWith mkEdg ens' (tail ens') ef = return $ \ as -> map ($as) efs parseAttrBased ef where mkEdg (_, hn) (et, tn) = DotEdge hn tn et instance Functor DotEdge where fmap f e = e { edgeFromNodeID = f $ edgeFromNodeID e , edgeToNodeID = f $ edgeToNodeID e } dirEdge :: String dirEdge = "->" dirEdge' :: DotCode dirEdge' = text dirEdge undirEdge :: String undirEdge = "--" undirEdge' :: DotCode undirEdge' = text undirEdge invalidEdge :: DotEdge a -> [DotError a] invalidEdge e = map (EdgeError eID) $ filter (not . usedByEdges) (edgeAttributes e) where eID = Just (edgeFromNodeID e, edgeToNodeID e) -- ----------------------------------------------------------------------------- -- Printing and parsing helpers. printAttrBased :: (a -> DotCode) -> (a -> Attributes) -> a -> DotCode printAttrBased ff fas a = dc <> semi where f = ff a dc = case fas a of [] -> f as -> f <+> toDot as printAttrBasedList :: (a -> DotCode) -> (a -> Attributes) -> [a] -> DotCode printAttrBasedList ff fas = vcat . map (printAttrBased ff fas) parseAttrBased :: Parse (Attributes -> a) -> Parse a parseAttrBased p = do f <- p whitespace' atts <- tryParseList lineEnd return $ f atts `adjustErr` (++ "\n\nNot a valid attribute-based structure") parseAttrBasedList :: Parse (Attributes -> a) -> Parse [a] parseAttrBasedList p = sepBy (whitespace' >> parseAttrBased p) newline' lineEnd :: Parse () lineEnd = whitespace' >> character ';' >> return ()