import type { Context } from "@wrnexus/core";
import { httpTransport, serviceClient } from "@wrnexus/rpc";
import { auditService, catalogService } from "../lib/contracts.ts";

interface GitHubRepository {
  full_name?: unknown;
  stargazers_count?: unknown;
}

function requestedSku(ctx: Context): string {
  return new URL(ctx.req.url).searchParams.get("sku")?.trim() || "starter";
}

/** GET /api/product-summary?sku=starter */
export async function GET(ctx: Context): Promise<Response> {
  const sku = requestedSku(ctx);
  const transport = httpTransport();

  // Inter-app call #1: query the catalog app. `{ as: ctx }` forwards the
  // signed subject/tenant context; catalog still authorizes independently.
  const catalog = serviceClient(catalogService, { app: "catalog", as: ctx, transport });
  const product = await catalog.getProduct({ sku });

  // External API call: GitHub's public repository endpoint. Do not send the
  // user's RPC identity token or internal headers to external services.
  let githubResponse: Response;
  try {
    githubResponse = await fetch("https://api.github.com/repos/octocat/Hello-World", {
      headers: { accept: "application/vnd.github+json", "user-agent": "wrnexus-example" },
      signal: ctx.req.signal,
    });
  } catch {
    return Response.json({ error: "External repository lookup failed." }, { status: 502 });
  }
  if (!githubResponse.ok) {
    return Response.json({ error: "External repository lookup failed." }, { status: 502 });
  }
  const github = (await githubResponse.json()) as GitHubRepository;
  if (typeof github.full_name !== "string" || typeof github.stargazers_count !== "number") {
    return Response.json(
      { error: "External repository returned an unexpected response." },
      { status: 502 },
    );
  }

  // Inter-app call #2: record the completed lookup in the audit app. This is
  // intentionally awaited: callers learn whether the audit record was saved.
  const audit = serviceClient(auditService, { app: "audit", as: ctx, transport });
  const receipt = await audit.recordLookup({
    sku: product.sku,
    repository: github.full_name,
    stars: github.stargazers_count,
  });

  return Response.json({
    product,
    external: { repository: github.full_name, stars: github.stargazers_count },
    audit: receipt,
  });
}