import type { RichContent } from "../../model/interfaces.ts";
import type { RichContentProvider } from "../rich-content-service.ts";
import { fetchWithTimeout } from "../rich-content-service.ts";

function extractVideoId(url: string): string | null {
  try {
    const u = new URL(url);
    if (u.hostname === "youtu.be") {
      return u.pathname.slice(1).split("/")[0] || null;
    }
    if (u.hostname === "youtube.com" || u.hostname === "www.youtube.com") {
      if (u.pathname === "/watch" || u.pathname.startsWith("/watch?")) {
        return u.searchParams.get("v");
      }
      if (
        u.pathname.startsWith("/embed/") || u.pathname.startsWith("/shorts/")
      ) {
        return u.pathname.split("/")[2] || null;
      }
    }
  } catch {
    // invalid URL
  }
  return null;
}

export const youtubeProvider: RichContentProvider = {
  name: "youtube",

  matches(url: string): boolean {
    return extractVideoId(url) !== null;
  },

  async fetch(url: string): Promise<RichContent> {
    const videoId = extractVideoId(url)!;
    const thumbnailUrl = `https://img.youtube.com/vi/${videoId}/hqdefault.jpg`;
    let title: string | undefined;

    try {
      const oembedUrl =
        `https://www.youtube.com/oembed?url=https://www.youtube.com/watch?v=${videoId}&format=json`;
      const res = await fetchWithTimeout(oembedUrl);
      if (res.ok) {
        const data = await res.json() as { title?: string };
        title = data.title;
      }
    } catch {
      // oembed failed — thumbnail still works
    }

    return {
      type: "youtube",
      siteName: "YouTube",
      url,
      videoId,
      title,
      thumbnailUrl,
      embedUrl: `https://www.youtube.com/embed/${videoId}?rel=0`,
    };
  },
};