From 6932e997744fe7ac8fbaa589211f6bb1a1901f08 Mon Sep 17 00:00:00 2001
From: Grigorii Kirgizov <grigorii.kirgizov@jetbrains.com>
Date: Wed, 22 May 2019 19:19:34 +0300
Subject: [PATCH] Enable tracking justification in Controller for principal
 constraints' occ-s

---
 .../jetbrains/mps/logic/reactor/core/Occurrence.kt |  2 ++
 .../logic/reactor/core/internal/ControllerImpl.kt  | 14 +++++++++-----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt b/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt
index 1e060e46..b1745dd9 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt
@@ -27,6 +27,8 @@ import jetbrains.mps.logic.reactor.program.Constraint
 
 
 typealias Justs = TIntSet
+//fun emptyJusts() = object : TIntSet {}
+fun emptyJusts() = TIntHashSet(1)
 fun justsOf(vararg elements: Int) = TIntHashSet(elements)
 fun justsFromCollection(collection: Collection<Int>) = TIntHashSet(collection)
 
diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
index cfa00c39..3ceea3d1 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
@@ -56,7 +56,7 @@ internal class ControllerImpl (
         // FIXME noLogicalContext
         val context = Context(NORMAL(), noLogicalContext)
 
-        activateConstraint(constraint, context)
+        activateConstraint(constraint, emptyJusts(), context)
 
         return context.currentStatus()
     }
@@ -133,9 +133,15 @@ internal class ControllerImpl (
 
             val savedPos = state.currentPos()
 
+            val currentJusts = state.justs()
+
             for (item in body) {
                 val itemOk = when (item) {
-                    is Constraint -> activateConstraint(item, context)
+                    is Constraint -> {
+                        // track justifications only for principal constraints
+                        val justs = if (item.isPrincipal) currentJusts else emptyJusts()
+                        activateConstraint(item, justs, context)
+                    }
                     is Predicate -> tellPredicate(item, context)
                     else -> throw IllegalArgumentException("unknown item ${item}")
                 }
@@ -188,12 +194,10 @@ internal class ControllerImpl (
         return context.currentStatus()
     }
     
-    private fun activateConstraint(constraint: Constraint, context: Context) : Boolean {
+    private fun activateConstraint(constraint: Constraint, justs: Justs, context: Context) : Boolean {
         val args = supervisor.instantiateArguments(constraint.arguments(), context.logicalContext, context)
         return context.eval { status ->
 
-//            val justs = if (constraint.isPrincipal) journal.justs() else justsOf()
-            val justs = justsOf()
             state.processActivated(constraint.occurrence(this, args, justs, context.logicalContext), status)
         }
     }