type Reference = { title: string; url: string; type: "image" | "video" };

export async function resolveTVstarGenerationReferences(
  references: Reference[],
  fetcher: typeof fetch = fetch,
) {
  const images = references.filter(item => item.type === "image").map(item => item.url).slice(0, 4);
  // The video processing endpoint accepts one active job per user, so extract sequentially.
  for (const item of references.filter(item => item.type === "video").slice(0, 2)) {
    const response = await fetcher("/api/canvas/video/process", {
      method: "POST", headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ operation: "frame", url: item.url, kind: "first", time: 0 }),
    });
    const result = await response.json();
    if (!response.ok || !result.success || !result.data?.url)
      throw new Error(`${item.title}：${result.error || "参考视频首帧提取失败"}`);
    images.push(String(result.data.url));
  }
  return [...new Set(images)].slice(0, 6);
}