refactor: cleanup

src-tauri/src/xray/error.rs

@@ -27,3 +27,42 @@ pub enum XrayError {
   #[error("failed to serialize Xray client configuration")]
   Serialization,
 }
+
+impl XrayError {
+  /// A stable, translatable identifier for *why* a URI was rejected.
+  ///
+  /// Donut supports one VLESS shape — REALITY + XTLS Vision over TCP — so most
+  /// rejections are "your setup is a kind we do not support", not "you made a
+  /// typo". The frontend turns these into a sentence naming the unsupported
+  /// part; without them every rejection reads as a malformed URI and a user
+  /// with a working WebSocket or plain-TLS server has no idea why it failed.
+  pub fn reason_code(&self) -> &'static str {
+    match self {
+      Self::UnsupportedScheme => "scheme",
+      Self::UnsupportedValue { field, .. } | Self::InvalidField { field, .. } => match *field {
+        "security" => "security",
+        "flow" => "flow",
+        "type" => "transport",
+        "encryption" => "encryption",
+        "headerType" => "headerType",
+        "fp" => "fingerprint",
+        // A malformed sni/public key is the same user-facing problem as a
+        // missing one, so it earns the same specific help rather than the
+        // generic "invalid URI".
+        "sni" | "server_name" => "sni",
+        "pbk" | "public_key" => "publicKey",
+        _ => "malformed",
+      },
+      Self::MissingField(field) => match *field {
+        "sni" => "sni",
+        "pbk" => "publicKey",
+        "security" => "security",
+        "flow" => "flow",
+        _ => "malformed",
+      },
+      Self::UnsupportedParameter(_) => "parameter",
+      Self::DuplicateParameter(_) => "malformed",
+      Self::InvalidUri | Self::Serialization => "malformed",
+    }
+  }
+}