Minor updates to overlap detection and segment coalescing logic

internal/backchannel/backchannel.go

@@ -3,6 +3,7 @@ package backchannel
 import (
 	"regexp"
 	"strings"
+	"unicode"
 
 	"gitea.maximumdirect.net/eric/seriatim/internal/model"
 )
@@ -10,16 +11,16 @@ import (
 const Category = "backchannel"
 
 var patterns = []*regexp.Regexp{
-	regexp.MustCompile(`(?i)^(yeah|yep|yes|right|okay|ok|sure|mm+h?m+|uh[- ]huh|mhm|mm-hmm)\.?$`),
+	regexp.MustCompile(`(?i)^(yeah|yep|yes|right|okay|ok|sure|mm+h?m+|mm+\s+hmm|uh[- ]huh|mhm|mm-hmm)\.?$`),
 	regexp.MustCompile(`(?i)^(yeah|yep|right|okay|ok)([,.\s]+(yeah|yep|right|okay|ok))*\.?$`),
-	regexp.MustCompile(`(?i)^(i see|got it|makes sense|that makes sense|fair enough|sounds good)\.?$`),
+	regexp.MustCompile(`(?i)^(i see|got it|makes sense|that makes sense|fair enough|sounds good|there you go)\.?$`),
 }
 
 // Apply tags matching short acknowledgement segments.
-func Apply(in model.MergedTranscript) (model.MergedTranscript, int) {
+func Apply(in model.MergedTranscript, maxDuration float64) (model.MergedTranscript, int) {
 	tagged := 0
 	for index := range in.Segments {
-		if !matches(in.Segments[index]) {
+		if !matches(in.Segments[index], maxDuration) {
 			continue
 		}
 		if hasCategory(in.Segments[index], Category) {
@@ -31,15 +32,15 @@ func Apply(in model.MergedTranscript) (model.MergedTranscript, int) {
 	return in, tagged
 }
 
-func matches(segment model.Segment) bool {
-	text := strings.TrimSpace(segment.Text)
+func matches(segment model.Segment, maxDuration float64) bool {
+	text := normalizeForMatching(segment.Text)
 	if text == "" {
 		return false
 	}
 	if len(strings.Fields(text)) > 3 {
 		return false
 	}
-	if segment.End-segment.Start > 1.0 {
+	if segment.End-segment.Start > maxDuration {
 		return false
 	}
 	for _, pattern := range patterns {
@@ -50,6 +51,16 @@ func matches(segment model.Segment) bool {
 	return false
 }
 
+func normalizeForMatching(text string) string {
+	text = strings.Map(func(r rune) rune {
+		if unicode.IsPunct(r) {
+			return ' '
+		}
+		return r
+	}, text)
+	return strings.Join(strings.Fields(text), " ")
+}
+
 func hasCategory(segment model.Segment, category string) bool {
 	for _, existing := range segment.Categories {
 		if existing == category {