import { createContexta } from "./server.ts";
import type { AdContext } from "./types.ts";
import type { ConversationMessage } from "./classify.ts";
export interface TrustedConversation {
  context: Omit<AdContext, "category" | "intent" | "opportunity" | "userTurn">;
  messages: ConversationMessage[];
  userTurn: number;
}
/** Framework-neutral Request -> Response route, with authentication supplied by the host.
 * Never implement loadContext by returning unverified JSON from the request body.
 */
export function createPartnerAdHandler(options: {
  baseUrl: string;
  apiKey: string;
  loadContext: (request: Request) => Promise<TrustedConversation | null>;
  classifier?: (messages: ConversationMessage[]) => Promise<unknown>;
  fetch?: typeof fetch;
}) {
  const client = createContexta(options);
  return async (request: Request): Promise<Response> => {
    const reply = (value: unknown, status = 200) =>
      Response.json(value, { status, headers: { "cache-control": "no-store" } });
    if (request.method !== "POST") return reply({ ad: null, reason: "method_not_allowed" }, 405);
    try {
      const conversation = await options.loadContext(request);
      if (!conversation) return reply({ ad: null, reason: "not_eligible" });
      return reply(await client.decideConversation(conversation));
    } catch {
      return reply({ ad: null, reason: "unavailable" });
    }
  };
}