From 3afab48323ab450f313aa00c720133d7774fb302 Mon Sep 17 00:00:00 2001
From: Marco Perone <pasafama@gmail.com>
Date: Tue, 4 Feb 2020 12:45:05 +0100
Subject: [PATCH] [#328] [stbx-core] split Transition module from WiringTree

---
 stbx-core/src/Statebox/Core/Transition.purs | 68 +++++++++++++++++++++
 stbx-core/src/Statebox/Core/WiringTree.purs | 34 ++---------
 stbx-protocol/spago.dhall                   |  4 +-
 3 files changed, 77 insertions(+), 29 deletions(-)
 create mode 100644 stbx-core/src/Statebox/Core/Transition.purs

diff --git a/stbx-core/src/Statebox/Core/Transition.purs b/stbx-core/src/Statebox/Core/Transition.purs
new file mode 100644
index 00000000..272c1439
--- /dev/null
+++ b/stbx-core/src/Statebox/Core/Transition.purs
@@ -0,0 +1,68 @@
+module Statebox.Core.Transition where
+
+import Prelude
+import Data.Array ((:))
+import Data.Foldable (foldr)
+import Data.FoldableWithIndex (foldrWithIndex)
+import Data.Map as Map
+import Data.Maybe (Maybe(..))
+
+import Data.ArrayMultiset (ArrayMultiset)
+import Statebox.Core.Execution (Path)
+import Statebox.Core.Types (PID, TID)
+
+-- TODO: these types are currently duplicated from Data.Petrinet.Representation.Dict
+type TransitionF p tok =
+  { pre  :: Array (PlaceMarkingF p tok)
+  , post :: Array (PlaceMarkingF p tok)
+  }
+
+type PlaceMarkingF p tok =
+  { place  :: p
+  , tokens :: tok
+  }
+
+buildTokens :: ∀ a. Ord a => ArrayMultiset a -> ArrayMultiset a -> TransitionF a Int
+buildTokens pre post =
+  { pre  : buildPlaceMarkings pre
+  , post : buildPlaceMarkings post
+  }
+
+buildPlaceMarkings :: ∀ a. Ord a => ArrayMultiset a -> Array (PlaceMarkingF a Int)
+buildPlaceMarkings multiset =
+  let map = foldr (Map.update (Just <<< (_ + 1))) Map.empty multiset
+  in foldrWithIndex (\place count -> (:) { place: place, tokens: count }) [] map
+
+type Tokens = Int
+
+type Transition =
+  { path       :: Path
+  , transition :: TID
+  , name       :: String
+  , tokens     :: TransitionF PID Tokens
+  }
+
+data Glued a
+  = Untouched a
+  | Initial a
+  | Final a
+  | Glued a a
+
+isInitial :: ∀ a. Glued a -> Boolean
+isInitial = case _ of
+  Initial a -> true
+  _         -> false
+
+isFinal :: ∀ a. Glued a -> Boolean
+isFinal = case _ of
+  Final a -> true
+  _       -> false
+
+gluedTokens :: Glued Transition -> TransitionF PID Tokens
+gluedTokens = case _ of
+  Untouched transition -> transition.tokens
+  Initial   transition -> transition.tokens
+  Final     transition -> transition.tokens
+  Glued transition1 transition2 -> { pre : transition1.tokens.pre
+                                   , post: transition2.tokens.post
+                                   }
diff --git a/stbx-core/src/Statebox/Core/WiringTree.purs b/stbx-core/src/Statebox/Core/WiringTree.purs
index d7fdbfe5..9edac66b 100644
--- a/stbx-core/src/Statebox/Core/WiringTree.purs
+++ b/stbx-core/src/Statebox/Core/WiringTree.purs
@@ -10,7 +10,7 @@ import Data.Tuple.Nested ((/\))
 
 import Data.ArrayMultiset (ArrayMultiset)
 import Data.Petrinet.Representation.NLL (ErrNetEncoding, TransitionF', fromNLL)
-import Statebox.Core.Execution (Path)
+import Statebox.Core.Transition (Glued(..), Transition, buildTokens, isInitial, isFinal)
 import Statebox.Core.Types (Diagram, Net, PID, TID, Wiring)
 
 data WiringTree
@@ -22,28 +22,6 @@ data WiringTree
 fromWiring :: Wiring -> Maybe WiringTree
 fromWiring wiring = Net <$> head wiring.nets
 
-type Transition =
-  { path       :: Path
-  , transition :: TID
-  , name       :: String
-  }
-
-data Glued a
-  = Untouched a
-  | Initial a
-  | Final a
-  | Glued a a
-
-isInitial :: ∀ a. Glued a -> Boolean
-isInitial = case _ of
-  Initial a -> true
-  _         -> false
-
-isFinal :: ∀ a. Glued a -> Boolean
-isFinal = case _ of
-  Final a -> true
-  _       -> false
-
 data LinearizationError
   = DiagramNotYetAllowed
   | NLLDecodingFailed ErrNetEncoding
@@ -65,11 +43,11 @@ linearizeTransitionsAndNames transitions names =
   sortInitialFinal $ lift3 buildGluedTransition (range 0 (length transitions - 1)) transitions names
 
 buildGluedTransition :: TID -> TransitionF' PID -> String -> Glued Transition
-buildGluedTransition tId (inputs /\ outputs) name =
-  case (inputs /\ outputs) of
-    ([]  /\ _  ) -> Initial   { name: name, path: [0, 0, 0], transition: tId } -- the path is [0, 0, 0] because we consider a trivial diagram to be there
-    (_   /\ [] ) -> Final     { name: name, path: [0, 0, 0], transition: tId }
-    (inp /\ out) -> Untouched { name: name, path: [0, 0, 0], transition: tId }
+buildGluedTransition tId (pre /\ post) name =
+  case (pre /\ post) of
+    ([]  /\ _  ) -> Initial   { name: name, path: [0, 0, 0], transition: tId, tokens: buildTokens pre post } -- the path is [0, 0, 0] because we consider a trivial diagram to be there
+    (_   /\ [] ) -> Final     { name: name, path: [0, 0, 0], transition: tId, tokens: buildTokens pre post }
+    (inp /\ out) -> Untouched { name: name, path: [0, 0, 0], transition: tId, tokens: buildTokens pre post }
 
 -- | We use this custom function instead of `sortBy` because that does not guarantee
 -- | the order of equal elements to be preserved.
diff --git a/stbx-protocol/spago.dhall b/stbx-protocol/spago.dhall
index bfcb21bb..a1bbeec0 100644
--- a/stbx-protocol/spago.dhall
+++ b/stbx-protocol/spago.dhall
@@ -3,8 +3,10 @@
 , name =
     "stbx-protocol"
 , dependencies =
-    [ "stbx-core"
+    [ "halogen-petrinet-editor"
+    , "stbx-core"
     , "stbx-tx-store"
+    , "studio-common"
     ]
 , packages =
     ./../packages.dhall