fix: resolve cyclop, funlen issues by extracting helper methods

internal/handlers/api.go

@@ -239,51 +239,53 @@ func (s *Handlers) HandleSendCommand() http.HandlerFunc {
 
 		req.Command = strings.ToUpper(strings.TrimSpace(req.Command))
 		req.To = strings.TrimSpace(req.To)
+		lines := extractBodyLines(req.Body)
 
-		// Helper to extract body as string lines.
-		bodyLines := func() []string {
-			switch v := req.Body.(type) {
-			case []any:
-				lines := make([]string, 0, len(v))
+		s.dispatchCommand(w, r, uid, nick, req.Command, req.To, lines)
+	}
+}
 
-				for _, item := range v {
-					if str, ok := item.(string); ok {
-						lines = append(lines, str)
-					}
-				}
+// extractBodyLines converts the request body to string lines.
+func extractBodyLines(body any) []string {
+	switch v := body.(type) {
+	case []any:
+		lines := make([]string, 0, len(v))
 
-				return lines
-			case []string:
-				return v
-			default:
-				return nil
+		for _, item := range v {
+			if str, ok := item.(string); ok {
+				lines = append(lines, str)
 			}
 		}
 
-		switch req.Command {
-		case "PRIVMSG", "NOTICE":
-			s.handlePrivmsg(w, r, uid, nick, req.To, bodyLines())
+		return lines
+	case []string:
+		return v
+	default:
+		return nil
+	}
+}
 
-		case "JOIN":
-			s.handleJoin(w, r, uid, req.To)
+func (s *Handlers) dispatchCommand(
+	w http.ResponseWriter, r *http.Request,
+	uid, nick, command, to string, lines []string,
+) {
+	switch command {
+	case "PRIVMSG", "NOTICE":
+		s.handlePrivmsg(w, r, uid, nick, to, lines)
+	case "JOIN":
+		s.handleJoin(w, r, uid, to)
+	case "PART":
+		s.handlePart(w, r, uid, to)
+	case "NICK":
+		s.handleNick(w, r, uid, lines)
+	case "TOPIC":
+		s.handleTopic(w, r, uid, to, lines)
+	case "PING":
+		s.respondJSON(w, r, map[string]string{"command": "PONG", "from": s.params.Config.ServerName}, http.StatusOK)
+	default:
+		_ = nick
 
-		case "PART":
-			s.handlePart(w, r, uid, req.To)
-
-		case "NICK":
-			s.handleNick(w, r, uid, bodyLines())
-
-		case "TOPIC":
-			s.handleTopic(w, r, uid, req.To, bodyLines())
-
-		case "PING":
-			s.respondJSON(w, r, map[string]string{"command": "PONG", "from": s.params.Config.ServerName}, http.StatusOK)
-
-		default:
-			_ = nick // suppress unused warning
-
-			s.respondJSON(w, r, map[string]string{"error": "unknown command: " + req.Command}, http.StatusBadRequest)
-		}
+		s.respondJSON(w, r, map[string]string{"error": "unknown command: " + command}, http.StatusBadRequest)
 	}
 }