Stabilize mobile auth session handling

lib/trpc-errors.ts

@@ -1,8 +1,121 @@
 import { TRPCClientError } from "@trpc/client";
 
-export function isUnauthorizedError(error: unknown): boolean {
+function errorMessage(error: unknown): string {
+  if (error instanceof TRPCClientError) return error.message;
+  if (error instanceof Error) return error.message;
+  if (typeof error === "object" && error !== null && "message" in error) {
+    const message = (error as { message: unknown }).message;
+    if (typeof message === "string") return message;
+  }
+  return "";
+}
+
+function errorStatus(error: unknown): number | undefined {
+  if (typeof error !== "object" || error === null || !("status" in error)) return undefined;
+  const status = (error as { status: unknown }).status;
+  return typeof status === "number" ? status : undefined;
+}
+
+export function parseRetryAfterSeconds(value: string | number | null | undefined): number | null {
+  if (value == null || value === "") return null;
+  const seconds = typeof value === "number" ? value : Number(value);
+  if (!Number.isFinite(seconds) || seconds <= 0) return null;
+  return Math.ceil(seconds);
+}
+
+export function isRateLimitError(error: unknown): boolean {
+  if (errorStatus(error) === 429) return true;
+
+  if (error instanceof TRPCClientError && error.data?.code === "TOO_MANY_REQUESTS") {
+    return true;
+  }
+
+  const message = errorMessage(error).toLowerCase();
   return (
-    error instanceof TRPCClientError &&
-    (error.data?.code === "UNAUTHORIZED" || error.message === "UNAUTHORIZED")
+    message.includes("too many") ||
+    message.includes("rate limit") ||
+    message.includes("try again later")
   );
 }
+
+export function isUnauthorizedError(error: unknown): boolean {
+  if (isRateLimitError(error)) return false;
+
+  if (error instanceof TRPCClientError) {
+    if (error.data?.code === "UNAUTHORIZED") return true;
+  }
+
+  if (errorStatus(error) === 401) return true;
+
+  const message = errorMessage(error).toLowerCase();
+  return message === "unauthorized" || message.includes("not authenticated");
+}
+
+export function formatRateLimitMessage(retryAfterSeconds?: number | null): string {
+  const retryAfter = parseRetryAfterSeconds(retryAfterSeconds ?? null);
+  if (retryAfter != null) {
+    if (retryAfter < 60) {
+      return `Too many attempts. Wait ${retryAfter} second${retryAfter === 1 ? "" : "s"} and try again.`;
+    }
+    const minutes = Math.ceil(retryAfter / 60);
+    return `Too many attempts. Wait about ${minutes} minute${minutes === 1 ? "" : "s"} and try again.`;
+  }
+  return "Too many attempts. Please wait a moment and try again.";
+}
+
+export function formatTrpcErrorMessage(error: unknown, fallback = "Something went wrong"): string {
+  if (isRateLimitError(error)) {
+    return formatRateLimitMessage();
+  }
+  if (isUnauthorizedError(error)) {
+    return "Your session expired. Sign in again to continue.";
+  }
+  if (error instanceof TRPCClientError) {
+    return error.message || fallback;
+  }
+  if (error instanceof Error) {
+    return error.message || fallback;
+  }
+  return fallback;
+}
+
+type AuthLikeError = {
+  message?: string;
+  status?: number;
+};
+
+export function formatAuthErrorMessage(error: AuthLikeError | null | undefined): string {
+  if (!error) return "Something went wrong";
+
+  if (isRateLimitError(error)) {
+    return formatRateLimitMessage();
+  }
+
+  const message = error.message ?? "";
+  if (message.toLowerCase().includes("internal") || message.includes("500")) {
+    return "Server error — is the API running with Postgres? Check beenvoice dev + docker.";
+  }
+
+  return message || "Invalid email or password";
+}
+
+export async function readHttpErrorMessage(response: Response): Promise<string> {
+  if (response.status === 429) {
+    const retryAfter = parseRetryAfterSeconds(
+      response.headers.get("x-retry-after") ?? response.headers.get("retry-after"),
+    );
+    return formatRateLimitMessage(retryAfter);
+  }
+
+  const data = (await response.json().catch(() => ({}))) as {
+    error?: string;
+    message?: string;
+  };
+
+  const message = data.error ?? data.message;
+  if (message && isRateLimitError({ message, status: response.status })) {
+    return formatRateLimitMessage();
+  }
+
+  return message ?? "Something went wrong";
+}