/**
 * Browser-side client for admin announcements.
 *
 * Deliberately thin: an announcement is fetched, shown once, and dismissed.
 * Nothing is cached client-side — "have I seen this?" is the server's answer,
 * so it survives a new device, a cleared browser, and a second tab.
 */

import type { MessageEntity } from "@/lib/chat";

const BFF_BASE = process.env.NEXT_PUBLIC_BFF_URL || "http://localhost:8080";

async function call<T>(path: string, init?: RequestInit): Promise<T> {
  const res = await fetch(`${BFF_BASE}/api/v1${path}`, {
    credentials: "include",
    headers: { "Content-Type": "application/json" },
    ...init,
  });
  if (!res.ok) throw new Error(`broadcast request failed: ${res.status}`);
  if (res.status === 204) return undefined as T;
  const body = (await res.json().catch(() => ({}))) as {
    data?: T;
    success?: boolean;
  };
  // NOT `body.data ?? body`: /pending answers {data: null} when nothing is
  // waiting, and `??` would fall through and hand back the whole envelope —
  // which is truthy, so the modal would try to render it as an announcement.
  return (body.data ?? (null as unknown as T)) as T;
}

export type Broadcast = {
  id: string;
  title: string;
  body: string;
  /** Formatting spans over `body`, same shape chat messages use. */
  entities: MessageEntity[];
  banner_url?: string | null;
  cta_label?: string | null;
  cta_url?: string | null;
  published_at?: string | null;
  expires_at?: string | null;
};

export const broadcasts = {
  /** The announcement waiting for this user, or null. */
  pending: () => call<Broadcast | null>("/broadcasts/pending"),

  /** Dismiss it. Idempotent, so a double-tap or two tabs are both fine. */
  markSeen: (id: string) =>
    call<void>(`/broadcasts/${id}/seen`, { method: "POST" }),
};