Implement "replacement" variable that simply replaces the match

processor/regex.go

@@ -213,29 +213,35 @@ func (p *RegexProcessor) ProcessContent(content string, pattern string, luaExpr
 			continue
 		}
 
-		// Apply the modifications to the original match
-		replacement := match
-		for i := len(modsMap) - 1; i >= 0; i-- {
-			newVal := modsMap[i]
-			log.Printf("Applying modification: %s", newVal)
-			// Indices of the group are relative to content
-			// To relate them to match we have to subtract the match start index
-			groupStart := groups[i*2] - matchIndices[0]
-			groupEnd := groups[i*2+1] - matchIndices[0]
-			replacement = replacement[:groupStart] + newVal + replacement[groupEnd:]
+		replacement := ""
+		replacementVar := L.GetGlobal("replacement")
+		if replacementVar.Type() != lua.LTNil {
+			replacement = replacementVar.String()
 		}
-
-		for i := len(namedCaptures) - 1; i >= 0; i-- {
-			capture := namedCaptures[i]
-			if capture.Name == "" {
-				continue
+		if replacement == "" {
+			// Apply the modifications to the original match
+			replacement = match
+			for i := len(modsMap) - 1; i >= 0; i-- {
+				newVal := modsMap[i]
+				log.Printf("Applying modification: %s", newVal)
+				// Indices of the group are relative to content
+				// To relate them to match we have to subtract the match start index
+				groupStart := groups[i*2] - matchIndices[0]
+				groupEnd := groups[i*2+1] - matchIndices[0]
+				replacement = replacement[:groupStart] + newVal + replacement[groupEnd:]
 			}
-			groupStart := capture.Range[0] - matchIndices[0]
-			groupEnd := capture.Range[1] - matchIndices[0]
-			luaValue := L.GetGlobal(capture.Name).String()
-			replacement = replacement[:groupStart] + luaValue + replacement[groupEnd:]
-		}
 
+			for i := len(namedCaptures) - 1; i >= 0; i-- {
+				capture := namedCaptures[i]
+				if capture.Name == "" {
+					continue
+				}
+				groupStart := capture.Range[0] - matchIndices[0]
+				groupEnd := capture.Range[1] - matchIndices[0]
+				luaValue := L.GetGlobal(capture.Name).String()
+				replacement = replacement[:groupStart] + luaValue + replacement[groupEnd:]
+			}
+		}
 		modificationCount++
 		result = result[:matchIndices[0]] + replacement + result[matchIndices[1]:]
 		log.Printf("Modification count updated: %d", modificationCount)