git-annex/Dot.hs
2011-02-08 18:17:46 -04:00

64 lines
1.7 KiB
Haskell

{- a simple graphviz / dot(1) digraph description generator library
-
- Copyright 2010 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Dot where -- import qualified
{- generates a graph description from a list of lines -}
graph :: [String] -> String
graph s = unlines $ [header] ++ map indent s ++ [footer]
where
header = "digraph map {"
footer= "}"
{- a node in the graph -}
graphNode :: String -> String -> String
graphNode nodeid desc = label desc $ quote nodeid
{- an edge between two nodes -}
graphEdge :: String -> String -> Maybe String -> String
graphEdge fromid toid desc = indent $
case desc of
Nothing -> edge
Just d -> label d edge
where
edge = quote fromid ++ " -> " ++ quote toid
{- adds a label to a node or edge -}
label :: String -> String -> String
label l s = attr "label" l s
{- adds an attribute to a node or edge
- (can be called multiple times for multiple attributes) -}
attr :: String -> String -> String -> String
attr a v s = s ++ " [ " ++ a ++ "=" ++ quote v ++ " ]"
{- fills a node with a color -}
fillColor :: String -> String -> String
fillColor color s = attr "fillcolor" color $ attr "style" "filled" $ s
{- apply to graphNode to put the node in a labeled box -}
subGraph :: String -> String -> String -> String -> String
subGraph subid l color s =
"subgraph " ++ name ++ " {\n" ++
ii setlabel ++
ii setcolor ++
ii s ++
indent "}"
where
-- the "cluster_" makes dot draw a box
name = quote ("cluster_" ++ subid)
setlabel = "label=" ++ quote l
setcolor = "fillcolor=" ++ quote color
ii x = (indent $ indent x) ++ "\n"
indent ::String -> String
indent s = "\t" ++ s
quote :: String -> String
quote s = "\"" ++ s' ++ "\""
where
s' = filter (/= '"') s