From a4bc3eec6c4554096bd819d7cb612011028d254f Mon Sep 17 00:00:00 2001
From: Marko Luukkainen <marko.luukkainen@semantum.fi>
Date: Thu, 28 Jan 2021 14:20:28 +0200
Subject: [PATCH] Prevent random matches when objects have the same difference
 value.

gitlab #30


Change-Id: I780893ed6ad9110188a5a70c336959b02a4acb40
---
 .../interop/test/GraphComparator.java         | 85 +++++++++++--------
 1 file changed, 50 insertions(+), 35 deletions(-)

diff --git a/org.simantics.interop/src/org/simantics/interop/test/GraphComparator.java b/org.simantics.interop/src/org/simantics/interop/test/GraphComparator.java
index a2724a5..0c5aecc 100644
--- a/org.simantics.interop/src/org/simantics/interop/test/GraphComparator.java
+++ b/org.simantics.interop/src/org/simantics/interop/test/GraphComparator.java
@@ -1083,7 +1083,7 @@ public class GraphComparator {
 		for (int i = 0; i < used2.length; i++) {
 			used2[i] = false;
 		}
-		
+				
 		// left, right, difference
 		List<List<Integer>> differences = new ArrayList<List<Integer>>();
 		for (int i1 = off1; i1 < off1 + len1; i1++) {
@@ -1115,41 +1115,12 @@ public class GraphComparator {
 		
 		Integer[] pris = priorities.getKeys(new Integer[]{});
 		Arrays.sort(pris);
+		boolean matchFail = priorityMatching(ss1, off1, len1, ss2, off2, len2, pris, differences, priorities, used1, used2, objectsLeft, objectsRight, false);
+		if (matchFail) 
+			matchFail = priorityMatching(ss1, off1, len1, ss2, off2, len2, pris, differences, priorities, used1, used2, objectsLeft, objectsRight, objectsLeft == null);
 		
 		for (Integer pri : pris) {
-			if (pri == Integer.MAX_VALUE) {
-
-			} else if (pri == 0) {
-				
-			} else {
-				List<Integer> i1s = priorities.getValues(pri);
-				for (Integer i1 : i1s) {
-					if (used1[i1])
-						continue;
-					List<Integer> i2diff = differences.get(i1);
-					for (int i2 = 0; i2 < i2diff.size(); i2++) {
-						if (i2diff.get(i2) == pri) {
-							if (used2[i2])
-								continue;
-							used1[i1] = true;
-							used2[i2] = true;
-							Statement s1  = ss1.get(i1+off1);
-							Statement s2  = ss2.get(i2+off2);
-							
-							if (objectsLeft != null) {
-								objectsLeft.add(s1.getObject());
-								objectsRight.add(s2.getObject());
-							} 
-							addComparable(s1, s2);
-							break;
-						}
-					}
-				}
-			}
-		}
-		
-		for (Integer pri : pris) {
-			if (pri != 0)
+			if (pri != 0 && !matchFail && unreliableLeft == null)
 				continue;
 			Set<Statement> s1s = new HashSet<Statement>();
 			Set<Statement> s2s = new HashSet<Statement>();
@@ -1197,7 +1168,51 @@ public class GraphComparator {
 		}
 	}
 	
-	
+	private boolean priorityMatching(List<Statement> ss1, int off1, int len1, List<Statement> ss2, int off2, int len2, Integer[] pris, List<List<Integer>> differences, MapList<Integer, Integer> priorities, boolean used1[],boolean used2[], Collection<Resource> objectsLeft, Collection<Resource> objectsRight, boolean force) throws DatabaseException {
+		boolean matchFail = false;
+		for (Integer pri : pris) {
+			if (pri == Integer.MAX_VALUE) {
+
+			} else if (pri == 0) {
+				
+			} else {
+				List<Integer> i1s = priorities.getValues(pri);
+				
+				for (Integer i1 : i1s) {
+					if (used1[i1])
+						continue;
+					List<Integer> i2diff = differences.get(i1);
+					List<Integer> matches = new ArrayList<Integer>();
+					for (int i2 = 0; i2 < i2diff.size(); i2++) {
+						if (i2diff.get(i2) == pri) { 
+							if (used2[i2])
+								continue;
+							matches.add(i2);
+						}
+					}
+					if (matches.size() == 1 || (force && matches.size() > 1)) {
+						int i2 = matches.get(0);
+						used1[i1] = true;
+						used2[i2] = true;
+						Statement s1  = ss1.get(i1+off1);
+						Statement s2  = ss2.get(i2+off2);
+						
+						if (objectsLeft != null) {
+							objectsLeft.add(s1.getObject());
+							objectsRight.add(s2.getObject());
+						} 
+						addComparable(s1, s2);
+					} else if (matches.size() > 1) {
+						matchFail = true;
+					}
+				}
+				if (matchFail)
+					break;
+			}
+		}
+		return matchFail;
+	}
+
 	
 	/**
 	 * compares properties, assumes functional relations
-- 
2.45.1