export function useApi() {
  async function api<T>(path: string, opts: RequestInit & { json?: unknown } = {}): Promise<T> {
    const headers = new Headers(opts.headers);
    if (opts.json !== undefined) headers.set("Content-Type", "application/json");
    const res = await fetch(path, {
      ...opts,
      headers,
      credentials: "include",
      body: opts.json !== undefined ? JSON.stringify(opts.json) : opts.body,
    });
    if (!res.ok) {
      const err = await res.json().catch(() => ({ error: res.statusText }));
      throw Object.assign(new Error(err.error || "Error"), { status: res.status, data: err });
    }
    const ct = res.headers.get("content-type") || "";
    if (ct.includes("application/json")) return await res.json() as T;
    return (await res.blob()) as T;
  }
  return { api };
}

export type SaasUser = {
  id: number;
  username: string;
  display_name: string;
  role?: string;
  realm?: string;
};

export const useAuth = () => {
  const user = useState<SaasUser | null>("saas-auth-user", () => null);
  const { api } = useApi();

  async function fetchMe() {
    try {
      const r = await api<{ user: SaasUser }>("/v1/auth/me");
      user.value = r.user;
    } catch {
      user.value = null;
    }
  }

  async function login(username: string, password: string) {
    const r = await api<{ user: SaasUser }>("/v1/auth/login", {
      method: "POST",
      json: { username, password },
    });
    if (r.user.role !== "platform_admin" || r.user.realm !== "platform") {
      await api("/v1/auth/logout", { method: "POST" });
      user.value = null;
      throw new Error("Esta consola es solo para administradores SaaS");
    }
    user.value = r.user;
  }

  async function logout() {
    await api("/v1/auth/logout", { method: "POST" });
    user.value = null;
    await navigateTo("/login");
  }

  return { user, fetchMe, login, logout };
};