fuxxy serch + rebuild script

internal/library/library.go

@@ -134,17 +134,67 @@ func (l *Library) Get(id string) (*MediaItem, string, bool) {
 	return item, item.fullPath, true
 }
 
-// Search returns items whose name contains the query (case-insensitive).
+// Search returns items matching the query, ranked by fuzzy match score.
 func (l *Library) Search(query string) []MediaItem {
 	q := strings.ToLower(query)
 	l.mu.RLock()
 	defer l.mu.RUnlock()
 
-	var results []MediaItem
+	type scored struct {
+		item  MediaItem
+		score int
+	}
+	var results []scored
 	for _, item := range l.items {
-		if strings.Contains(strings.ToLower(item.Name), q) {
-			results = append(results, item)
+		name := strings.ToLower(item.Name)
+		if s := fuzzyScore(name, q); s > 0 {
+			results = append(results, scored{item, s})
 		}
 	}
-	return results
+	sort.Slice(results, func(i, j int) bool {
+		return results[i].score > results[j].score
+	})
+
+	items := make([]MediaItem, len(results))
+	for i, r := range results {
+		items[i] = r.item
+	}
+	return items
+}
+
+// fuzzyScore returns a match score for how well target matches the query.
+// Returns 0 if no match. Higher is better.
+// Exact substring match gets a big bonus. Otherwise uses subsequence matching
+// with bonuses for consecutive chars and word-boundary matches.
+func fuzzyScore(target, query string) int {
+	// exact substring = best possible match
+	if strings.Contains(target, query) {
+		return 1000 + len(query)*10
+	}
+
+	// subsequence match with scoring
+	qi := 0
+	score := 0
+	consecutive := 0
+	for ti := 0; ti < len(target) && qi < len(query); ti++ {
+		if target[ti] == query[qi] {
+			score += 10
+			consecutive++
+			if consecutive > 1 {
+				score += consecutive * 5 // bonus for runs
+			}
+			// word boundary bonus
+			if ti == 0 || target[ti-1] == ' ' || target[ti-1] == '.' || target[ti-1] == '_' || target[ti-1] == '-' {
+				score += 20
+			}
+			qi++
+		} else {
+			consecutive = 0
+		}
+	}
+
+	if qi < len(query) {
+		return 0 // didn't match all query chars
+	}
+	return score
 }