feat: password protected profiles

src/lib/backend-errors.ts

@@ -0,0 +1,121 @@
+import type { TFunction } from "i18next";
+
+/**
+ * Backend error codes returned from Rust Tauri commands.
+ * Keep this list in sync with the codes used in `src-tauri/src/profile/password.rs`.
+ */
+export type BackendErrorCode =
+  | "INCORRECT_PASSWORD"
+  | "LOCKED_OUT"
+  | "PROFILE_NOT_FOUND"
+  | "PROFILE_NOT_PROTECTED"
+  | "PROFILE_ALREADY_PROTECTED"
+  | "PROFILE_RUNNING"
+  | "PROFILE_MISSING_SALT"
+  | "PROFILE_LOCKED"
+  | "INVALID_PROFILE_ID"
+  | "PASSWORD_TOO_SHORT"
+  | "INTERNAL_ERROR";
+
+export interface BackendError {
+  code: BackendErrorCode;
+  params?: Record<string, string>;
+}
+
+/**
+ * Try to parse a backend error string as a structured `{code, params}` payload.
+ * Returns null if the string isn't structured (e.g. raw error from a command
+ * that doesn't yet emit codes — caller should fall back to showing the raw text).
+ */
+export function parseBackendError(err: unknown): BackendError | null {
+  const message = err instanceof Error ? err.message : String(err);
+  if (!message.startsWith("{")) return null;
+  try {
+    const parsed = JSON.parse(message);
+    if (
+      parsed &&
+      typeof parsed === "object" &&
+      typeof parsed.code === "string"
+    ) {
+      return parsed as BackendError;
+    }
+  } catch {
+    // not JSON
+  }
+  return null;
+}
+
+/**
+ * Translate a backend error to a localized string. Falls back to the raw
+ * message if the error isn't a structured backend error.
+ */
+export function translateBackendError(t: TFunction, err: unknown): string {
+  const parsed = parseBackendError(err);
+  if (!parsed) {
+    return err instanceof Error ? err.message : String(err);
+  }
+  switch (parsed.code) {
+    case "INCORRECT_PASSWORD":
+      return t("backendErrors.incorrectPassword");
+    case "LOCKED_OUT": {
+      const seconds = Number.parseInt(parsed.params?.seconds ?? "0", 10);
+      return t("backendErrors.lockedOut", {
+        duration: formatLockoutDuration(t, seconds),
+      });
+    }
+    case "PROFILE_NOT_FOUND":
+      return t("backendErrors.profileNotFound");
+    case "PROFILE_NOT_PROTECTED":
+      return t("backendErrors.profileNotProtected");
+    case "PROFILE_ALREADY_PROTECTED":
+      return t("backendErrors.profileAlreadyProtected");
+    case "PROFILE_RUNNING":
+      return t("backendErrors.profileRunning");
+    case "PROFILE_MISSING_SALT":
+      return t("backendErrors.profileMissingSalt");
+    case "PROFILE_LOCKED":
+      return t("backendErrors.profileLocked");
+    case "INVALID_PROFILE_ID":
+      return t("backendErrors.invalidProfileId");
+    case "PASSWORD_TOO_SHORT": {
+      const min = Number.parseInt(parsed.params?.min ?? "8", 10);
+      return t("backendErrors.passwordTooShort", { min });
+    }
+    case "INTERNAL_ERROR":
+      return t("backendErrors.internal", {
+        detail: parsed.params?.detail ?? "",
+      });
+    default:
+      return err instanceof Error ? err.message : String(err);
+  }
+}
+
+export function formatLockoutDuration(t: TFunction, seconds: number): string {
+  if (seconds < 60)
+    return t("backendErrors.lockedOutDuration.seconds", { seconds });
+  const minutes = Math.ceil(seconds / 60);
+  if (minutes < 60)
+    return t("backendErrors.lockedOutDuration.minutes", { minutes });
+  const hours = Math.ceil(minutes / 60);
+  return t("backendErrors.lockedOutDuration.hours", { hours });
+}
+
+/**
+ * Extract the lockout countdown in seconds from a backend error, or null.
+ */
+export function extractLockoutSeconds(err: unknown): number | null {
+  const parsed = parseBackendError(err);
+  if (parsed?.code !== "LOCKED_OUT") return null;
+  const secs = Number.parseInt(parsed.params?.seconds ?? "0", 10);
+  return Number.isFinite(secs) && secs > 0 ? secs : null;
+}
+
+/**
+ * True if the error is a known structured backend error code.
+ */
+export function isBackendErrorCode(
+  err: unknown,
+  code: BackendErrorCode,
+): boolean {
+  return parseBackendError(err)?.code === code;
+}