{-# 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: <http://graphviz.org/doc/info/lang.html> 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. * It is not yet possible to create or parse 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@. * 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 pre-processor lines, join together multiline statements and concatenate split strings together. However, pre-processing within HTML-like labels is currently not supported. * Graphviz allows a node to be \"defined\" twice (e.g. the actual node definition, and then in a subgraph with extra global attributes applied to it). This actually represents the same node, but when parsing they will be considered as separate 'DotNode's (such that 'graphNodes' will return both \"definitions\"). The canonical form (see @prettyPrint@ in "Data.GraphViz") combines the \"definitions\" into one. See "Data.GraphViz.Attributes" for more limitations. -} module Data.GraphViz.Types ( -- * Abstraction from the representation type DotRepr(..) -- ** Helper types for looking up information within a @DotRepr@. , ClusterLookup , NodeLookup , Path -- ** Obtaining the @DotNode@s and @DotEdges@. , graphNodes , graphEdges -- ** 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(..) -- Re-exported from Data.GraphViz.Types.Common , DotStatements(..) , GlobalAttributes(..) -- Re-exported from Data.GraphViz.Types.Common , DotSubGraph(..) , DotNode(..) , DotEdge(..) -- Re-exported from Data.GraphViz.Types.Common ) where import Data.GraphViz.Types.Common import Data.GraphViz.Types.State import Data.GraphViz.Attributes( Attribute , usedByGraphs, usedByClusters, usedBySubGraphs) import Data.GraphViz.Util import Data.GraphViz.Parsing import Data.GraphViz.PreProcessing import Data.GraphViz.Printing import Control.Arrow((&&&)) 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 -- | Return the ID of the graph. getID :: dg n -> Maybe GraphID -- | Is this graph directed? graphIsDirected :: dg n -> Bool -- | Is this graph strict? graphIsStrict :: 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 information on all the clusters contained within this -- 'DotRepr', as well as the top-level 'GraphAttrs' for the -- overall graph. graphStructureInformation :: dg n -> (GlobalAttributes, ClusterLookup) -- | Return information on the 'DotNode's contained within this -- 'DotRepr'. The 'Bool' parameter indicates if applicable -- 'NodeAttrs' should be included. nodeInformation :: Bool -> dg n -> NodeLookup n -- | Return information on the 'DotEdge's contained within this -- 'DotRepr'. The 'Bool' parameter indicates if applicable -- 'EdgeAttrs' should be included. edgeInformation :: Bool -> dg n -> [DotEdge n] -- | Returns all resultant 'DotNode's in the 'DotRepr' (not including -- 'NodeAttr's). graphNodes :: (DotRepr dg n, Ord n) => dg n -> [DotNode n] graphNodes = toDotNodes . nodeInformation True -- | Returns all resultant 'DotEdge's in the 'DotRepr' (not including -- 'EdgeAttr's). graphEdges :: (DotRepr dg n) => dg n -> [DotEdge n] graphEdges = edgeInformation True -- | 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 (Ord n, PrintDot n, ParseDot n) => DotRepr DotGraph n where getID = graphID graphIsDirected = directedGraph graphIsStrict = strictGraph makeStrict g = g { strictGraph = True } setID i g = g { graphID = Just i } graphStructureInformation = getGraphInfo . statementStructure . graphStatements nodeInformation wGlobal = getNodeLookup wGlobal . statementNodes . graphStatements edgeInformation wGlobal = getDotEdges wGlobal . 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 } -- ----------------------------------------------------------------------------- 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) statementStructure :: DotStatements n -> GraphState () statementStructure stmts = do mapM_ addGraphGlobals $ attrStmts stmts mapM_ (withSubGraphID addSubGraph statementStructure) $ subGraphs stmts statementNodes :: (Ord a) => DotStatements a -> NodeState a () statementNodes stmts = do mapM_ addNodeGlobals $ attrStmts stmts mapM_ (withSubGraphID recursiveCall statementNodes) $ subGraphs stmts mapM_ addNode $ nodeStmts stmts mapM_ addEdgeNodes $ edgeStmts stmts statementEdges :: DotStatements a -> EdgeState a () statementEdges stmts = do mapM_ addEdgeGlobals $ attrStmts stmts mapM_ (withSubGraphID recursiveCall statementEdges) $ subGraphs stmts mapM_ addEdge $ edgeStmts stmts -- ----------------------------------------------------------------------------- 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 (isCluster &&& subGraphID) instance (ParseDot a) => ParseDot (DotSubGraph a) where parseUnqt = parseStmtBased parseUnqt (parseSubGraphID DotSG) `onFail` -- Take "anonymous" DotSubGraphs into account. liftM (DotSG False Nothing) (parseBracesBased parseUnqt) parse = parseUnqt -- Don't want the option of quoting `adjustErr` (++ "\n\nNot a valid Sub Graph") parseUnqtList = sepBy (whitespace' >> parseUnqt) newline' 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) withSubGraphID :: (Maybe (Maybe GraphID) -> b -> a) -> (DotStatements n -> b) -> DotSubGraph n -> a withSubGraphID f g sg = f mid . g $ subGraphStmts sg where mid = bool Nothing (Just $ subGraphID sg) $ isCluster sg