Clean up regex.go a little

processor/regex.go

@@ -44,13 +44,18 @@ func ProcessRegex(content string, command utils.ModifyCommand) ([]utils.ReplaceC
 	// Process all regex matches
 	indices := compiledPattern.FindAllStringSubmatchIndex(content, -1)
 	logger.Debug("Found %d matches in content of length %d", len(indices), len(content))
+	if len(indices) == 0 {
+		logger.Warning("No matches found for regex: %q", pattern)
+		return commands, nil
+	}
 
 	// We walk backwards because we're replacing something with something else that might be longer
 	// And in the case it is longer than the original all indicces past that change will be fucked up
 	// By going backwards we fuck up all the indices to the end of the file that we don't care about
 	// Because there either aren't any (last match) or they're already modified (subsequent matches)
-	for i := len(indices) - 1; i >= 0; i-- {
+	for i, matchIndices := range indices {
 		logger.Debug("Processing match %d of %d", i+1, len(indices))
+		logger.Trace("Match indices: %v (match position %d-%d)", matchIndices, matchIndices[0], matchIndices[1])
 
 		L, err := NewLuaState()
 		if err != nil {
@@ -63,9 +68,6 @@ func ProcessRegex(content string, command utils.ModifyCommand) ([]utils.ReplaceC
 		defer L.Close()
 		logger.Trace("Lua state created successfully for match %d", i+1)
 
-		matchIndices := indices[i]
-		logger.Trace("Match indices: %v (match position %d-%d)", matchIndices, matchIndices[0], matchIndices[1])
-
 		// Why we're doing this whole song and dance of indices is to properly handle empty matches
 		// Plus it's a little cleaner to surgically replace our matches
 		// If we were to use string.replace and encountered an empty match there'd be nothing to replace
@@ -182,11 +184,11 @@ func ProcessRegex(content string, command utils.ModifyCommand) ([]utils.ReplaceC
 					modifiedGroups++
 				}
 			}
-			logger.Debug("%d of %d capture groups were modified", modifiedGroups, len(captureGroups))
+			logger.Info("%d of %d capture groups were modified", modifiedGroups, len(captureGroups))
 
 			for _, capture := range captureGroups {
 				if capture.Value == capture.Updated {
-					logger.Trace("Capture group unchanged: %s", capture.Value)
+					logger.Info("Capture group unchanged: %s", capture.Value)
 					continue
 				}
 
@@ -198,11 +200,17 @@ func ProcessRegex(content string, command utils.ModifyCommand) ([]utils.ReplaceC
 				// To relate them to match we have to subtract the match start index
 				// replacement = replacement[:groupStart] + newVal + replacement[groupEnd:]
 				commands = append(commands, utils.ReplaceCommand{
-					From: capture.Range[0] - matchIndices[0],
-					To:   capture.Range[1] - matchIndices[0],
+					From: capture.Range[0],
+					To:   capture.Range[1],
 					With: capture.Updated,
 				})
 			}
+		} else {
+			commands = append(commands, utils.ReplaceCommand{
+				From: matchIndices[0],
+				To:   matchIndices[1],
+				With: replacement,
+			})
 		}
 	}