# UNDF: UNDF-2026-000000803
# UNDF: (leave blank)
# scribus-0002: getUsedPatterns results.contains O(I×R) pattern collection
#
# In scribus/scribusdoc.cpp, getUsedPatterns() iterates over all page items
# and for each checks results.contains(pattern) — a QStringList linear scan
# O(R) where R is the number of results accumulated so far. With I page items
# each potentially contributing 3 pattern names (fill, stroke, mask), the
# overall complexity is O(3×I×R). For a document with 2000 items and 200
# patterns, that is ~1.2M string comparisons.
#
# The same pattern repeats in getUsedPatternsSelection() and
# getUsedPatternsHelper() and getPatternDependencyList().
#
# Fix: maintain a companion QSet<QString> for O(1) membership alongside the
# QStringList for ordered results.
#
# Severity: MEDIUM — triggered during document save, export, and pattern
# cleanup; scales with item count × pattern count.
--- a/scribus/scribusdoc.cpp
+++ b/scribus/scribusdoc.cpp
@@ -3933,6 +3933,7 @@
 QStringList ScribusDoc::getUsedPatterns() const
 {
 	QStringList results;
+	QSet<QString> resultSet;

 	for (PageItemIterator it(this, ...); *it; ++it)
 	{
 		const PageItem* currItem = *it;
-		if ((!results.contains(currItem->pattern())) && ...)
+		if ((!resultSet.contains(currItem->pattern())) && ...)
+		{
 			results.append(currItem->pattern());
+			resultSet.insert(currItem->pattern());
+		}
 		if (!currItem->strokePattern().isEmpty())
 		{
-			if (!results.contains(currItem->strokePattern()))
+			if (!resultSet.contains(currItem->strokePattern()))
+			{
 				results.append(currItem->strokePattern());
+				resultSet.insert(currItem->strokePattern());
+			}
 		}
 		if (!currItem->patternMask().isEmpty())
 		{
-			if (!results.contains(currItem->patternMask()))
+			if (!resultSet.contains(currItem->patternMask()))
+			{
 				results.append(currItem->patternMask());
+				resultSet.insert(currItem->patternMask());
+			}
 		}
 	}

 	// Same fix for the inner docPatterns loop (lines 3955-3983)
-	// Replace results.contains(...) with resultSet.contains(...)
+	// and add resultSet.insert(...) after each results.append(...)

 	return results;
 }

 // Same fix applies to:
 //   getUsedPatternsSelection()   (line 3988)
 //   getUsedPatternsHelper()      (line 4036)
 //   getPatternDependencyList()   (line 4087)