const https = require("https");
const fs = require("fs");
const path = require("path");

function thumbnailRouteHandler(app) {
  const cacheDir = path.join(__dirname, "../cache");
  if (!fs.existsSync(cacheDir)) {
    fs.mkdirSync(cacheDir);
  }

  setInterval(() => {
    fs.readdir(cacheDir, (err, files) => {
      if (err) {
        console.error("Error reading cache directory:", err);
        return;
      }
      
      const now = Date.now();
      files.forEach(file => {
        const filePath = path.join(cacheDir, file);
        fs.stat(filePath, (err, stats) => {
          if (err) {
            console.error("Error getting file stats:", err);
            return;
          }
          
          if (now - stats.mtime.getTime() > 30 * 24 * 60 * 60 * 1000) {
            fs.unlink(filePath, err => {
              if (err) console.error("Error deleting cached file:", err);
            });
          }
        });
      });
    });
  }, 24 * 60 * 60 * 1000);

  app.get("/api/thumbnail/:videoId", (req, res) => {
    const videoId = req.params.videoId;
    const cachePath = path.join(cacheDir, `${videoId}.jpg`);

    if (fs.existsSync(cachePath)) {
      return fs.createReadStream(cachePath).pipe(res);
    }

    const thumbnailUrl = `https://img.youtube.com/vi/${videoId}/maxresdefault.jpg`;

    https.get(thumbnailUrl, (response) => {
      if (response.statusCode === 404) {
        const fallbackUrl = `https://img.youtube.com/vi/${videoId}/hqdefault.jpg`;
        https.get(fallbackUrl, (fallbackResponse) => {
          const fileStream = fs.createWriteStream(cachePath);
          fallbackResponse.pipe(fileStream);
          fallbackResponse.pipe(res);
        }).on("error", (err) => {
          console.error(`Error fetching fallback thumbnail: ${err.message}`);
          res.status(500).send("Error fetching thumbnail");
        });
        return;
      }
      
      const fileStream = fs.createWriteStream(cachePath);
      response.pipe(fileStream);
      response.pipe(res);
    }).on("error", (err) => {
      console.error(`Error fetching thumbnail: ${err.message}`);
      res.status(500).send("Error fetching thumbnail");
    });
  });
}

module.exports = thumbnailRouteHandler;