[Graph] fix Louvain edge colouring

src/Gargantext/Components/Graph.purs

@@ -9,7 +9,6 @@ import Prelude (bind, const, discard, not, pure, unit, ($))
 import Data.Either (Either(..))
 import Data.Maybe (Maybe(..))
 import Data.Nullable (Nullable)
-import Data.Sequence as Seq
 import Data.Tuple.Nested ((/\))
 import DOM.Simple.Console (log, log2)
 import DOM.Simple.Types (Element)
@@ -17,7 +16,6 @@ import FFI.Simple (delay)
 import Reactix as R
 import Reactix.DOM.HTML as RH
 
-import Gargantext.Data.Louvain as Louvain
 import Gargantext.Hooks.Sigmax as Sigmax
 import Gargantext.Hooks.Sigmax.Types as SigmaxTypes
 import Gargantext.Hooks.Sigmax.Sigma as Sigma

src/Gargantext/Hooks/Sigmax/Types.purs

@@ -173,7 +173,17 @@ louvainGraph g cluster = Graph {nodes: newNodes, edges: newEdges}
     edges = graphEdges g
 
     newNodes = (nodeClusterColor cluster) <$> nodes
-    newEdges = edges
+    nm = nodesMap newNodes
+    newEdges = (edgeClusterColor cluster nm) <$> edges
+
+edgeClusterColor cluster nm e = e { color = sourceNode.color, sourceNode = sourceNode, targetNode = targetNode }
+  where
+    sourceNode = case Map.lookup e.source nm of
+      Just sn -> sn
+      Nothing -> e.sourceNode
+    targetNode = case Map.lookup e.target nm of
+      Just tn -> tn
+      Nothing -> e.targetNode
 
 nodeClusterColor cluster n = n { color = newColor }
   where