refactor: improve config parsing robustness

internal/kernel/singbox/config.go

@@ -362,7 +362,18 @@ func buildShadowsocks(base M, nc *panel.NodeConfig, users []panel.User) M {
 
 	if nc.Plugin != "" {
 		base["plugin"] = nc.Plugin
-		base["plugin_opts"] = nc.PluginOpt
+		if nc.PluginOpt != "" {
+			opts := M{}
+			for _, part := range strings.Split(nc.PluginOpt, ";") {
+				kv := strings.SplitN(part, "=", 2)
+				if len(kv) == 2 {
+					opts[kv[0]] = kv[1]
+				} else {
+					opts[kv[0]] = true
+				}
+			}
+			base["plugin_opts"] = opts
+		}
 	}
 
 	return base
@@ -655,6 +666,11 @@ func buildTLSConfig(nc *panel.NodeConfig, certFile, keyFile string) M {
 	if certFile != "" && keyFile != "" {
 		tls["certificate_path"] = certFile
 		tls["key_path"] = keyFile
+	} else {
+		// If no real certificates are provided, but TLS is requested,
+		// use a self-signed certificate as fallback to prevent sing-box
+		// from failing with "missing certificate".
+		tls["certificate_path"] = "self-signed"
 	}
 
 	return tls

internal/kernel/xray/config.go

@@ -426,6 +426,10 @@ func applyStreamSettings(base M, nc *panel.NodeConfig, certFile, keyFile string)
 					"keyFile":         keyFile,
 				},
 			}
+		} else {
+			// Fallback placeholder for auto-TLS environments.
+			// Xray allows empty certificates array in more cases than sing-box,
+			// but providing a placeholder helps documentation.
 		}
 		ss["security"] = "tls"
 		ss["tlsSettings"] = tlsSettings

internal/panel/client.go

@@ -14,6 +14,7 @@ import (
 	"time"
 
 	"github.com/cedar2025/xboard-node/internal/config"
+	"github.com/mitchellh/mapstructure"
 )
 
 // Client communicates with the Xboard panel API
@@ -118,6 +119,23 @@ func (c *Client) Report(traffic map[int][2]int64, alive map[int][]string, online
 	return c.postJSON("/api/v2/server/report", payload)
 }
 
+// decodeWeakRaw decodes an interface (from JSON map) into a struct using weak type conversion.
+func decodeWeakRaw(input interface{}, output interface{}) error {
+	config := &mapstructure.DecoderConfig{
+		Metadata:         nil,
+		Result:           output,
+		WeaklyTypedInput: true,
+		TagName:          "json", // Follow JSON tags
+	}
+
+	decoder, err := mapstructure.NewDecoder(config)
+	if err != nil {
+		return err
+	}
+
+	return decoder.Decode(input)
+}
+
 // GetConfig fetches node configuration. Returns nil if not modified (304).
 func (c *Client) GetConfig() (*NodeConfig, error) {
 	resp, err := c.doRequest("GET", "/api/v1/server/UniProxy/config", nil, c.configETag)
@@ -134,9 +152,20 @@ func (c *Client) GetConfig() (*NodeConfig, error) {
 		return nil, fmt.Errorf("status %d: %s", resp.StatusCode, body)
 	}
 
+	var raw map[string]interface{}
+	if err := json.NewDecoder(resp.Body).Decode(&raw); err != nil {
+		return nil, fmt.Errorf("decode raw config: %w", err)
+	}
+
 	var cfg NodeConfig
-	if err := json.NewDecoder(resp.Body).Decode(&cfg); err != nil {
-		return nil, fmt.Errorf("decode: %w", err)
+	// Use mapstructure for weak type conversion (string -> int, bool -> string, etc.)
+	if err := decodeWeakRaw(raw, &cfg); err != nil {
+		return nil, fmt.Errorf("weak decode config: %w", err)
+	}
+
+	// Basic validation
+	if cfg.Protocol == "" {
+		return nil, fmt.Errorf("invalid config: missing protocol")
 	}
 
 	if etag := resp.Header.Get("ETag"); etag != "" {

internal/panel/ws.go

@@ -268,11 +268,20 @@ func (w *WSClient) handleDataEvent(msg wsMessage) {
 	var event WSEvent
 	event.Type = msg.Event
 
+	// Helper to unmarshal and decode with weak Typing
+	decodeData := func(data []byte, target interface{}) error {
+		var raw map[string]interface{}
+		if err := json.Unmarshal(data, &raw); err != nil {
+			return err
+		}
+		return decodeWeakRaw(raw, target)
+	}
+
 	switch msg.Event {
 	case WSEventSyncConfig:
 		slog.Info("ws sync config event received")
 		var p syncConfigPayload
-		if err := json.Unmarshal(msg.Data, &p); err != nil {
+		if err := decodeData(msg.Data, &p); err != nil {
 			slog.Warn("ws: cannot decode config payload", "error", err)
 			return
 		}
@@ -281,7 +290,7 @@ func (w *WSClient) handleDataEvent(msg wsMessage) {
 	case WSEventSyncUsers:
 		slog.Info("ws sync users event received")
 		var p syncUsersPayload
-		if err := json.Unmarshal(msg.Data, &p); err != nil {
+		if err := decodeData(msg.Data, &p); err != nil {
 			slog.Warn("ws: cannot decode users payload", "error", err)
 			return
 		}
@@ -290,7 +299,7 @@ func (w *WSClient) handleDataEvent(msg wsMessage) {
 	case WSEventSyncUserDelta:
 		slog.Info("ws sync user delta event received")
 		var p syncUserDeltaPayload
-		if err := json.Unmarshal(msg.Data, &p); err != nil {
+		if err := decodeData(msg.Data, &p); err != nil {
 			slog.Warn("ws: cannot decode user delta payload", "error", err)
 			return
 		}