// Typed fetch wrappers for the /api/auth/* surface (SD-0001 §6.4). Same-origin via the Vite
// proxy; cookies carry the session. Errors return the §6.4 envelope; helpers normalize them.
import type { SessionState } from "./routing";

export interface ApiError {
  code: string;
  message: string;
  retry_after_s?: number;
  attempts_remaining?: number;
}

export interface VerifyResult {
  account: { email: string };
  storefront: { id: number; name: string } | null;
  created: boolean;
}

export async function errorOf(resp: Response): Promise<ApiError> {
  try {
    const body = await resp.json();
    if (body && body.error) return body.error as ApiError;
  } catch {
    /* fall through */
  }
  return { code: "unexpected", message: "Something went wrong. Please try again." };
}

export async function getMe(): Promise<SessionState | null> {
  const resp = await fetch("/api/auth/me", { credentials: "include" });
  if (resp.status === 401) return null;
  if (!resp.ok) return null;
  return (await resp.json()) as SessionState;
}

export async function requestCode(email: string): Promise<ApiError | null> {
  const resp = await fetch("/api/auth/request-code", {
    method: "POST",
    headers: { "content-type": "application/json" },
    credentials: "include",
    body: JSON.stringify({ email }),
  });
  return resp.ok ? null : await errorOf(resp);
}

export async function verifyCode(
  email: string,
  code: string,
): Promise<{ ok: true; result: VerifyResult } | { ok: false; error: ApiError }> {
  const resp = await fetch("/api/auth/verify", {
    method: "POST",
    headers: { "content-type": "application/json" },
    credentials: "include",
    body: JSON.stringify({ email, code }),
  });
  if (resp.ok) return { ok: true, result: (await resp.json()) as VerifyResult };
  return { ok: false, error: await errorOf(resp) };
}

export async function logout(): Promise<void> {
  await fetch("/api/auth/logout", { method: "POST", credentials: "include" });
}

export interface StorefrontResult {
  id: number;
  name: string;
}

export async function createStorefront(
  name: string,
): Promise<{ ok: true; storefront: StorefrontResult } | { ok: false; error: ApiError }> {
  const resp = await fetch("/api/storefronts", {
    method: "POST",
    headers: { "content-type": "application/json" },
    credentials: "include",
    body: JSON.stringify(name.trim() ? { name: name.trim() } : {}),
  });
  if (resp.ok) return { ok: true, storefront: (await resp.json()) as StorefrontResult };
  return { ok: false, error: await errorOf(resp) };
}