// appMetadata.js
import axios from "axios";
import * as cheerio from "cheerio";
import sizeOf from "image-size";
import sharp from "sharp";

export async function getAppMetadata(baseUrl) {
  console.log(baseUrl);
  try {
    const res = await axios.get(baseUrl, { timeout: 3000 });
    const $ = cheerio.load(res.data);

    // -------------------------------
    // 1. Nome più corto
    // -------------------------------
    const nameCandidates = [
      $('meta[property="og:site_name"]').attr("content"),
      $('meta[name="application-name"]').attr("content"),
      $('meta[property="og:title"]').attr("content"),
      $("title").text().trim()
    ].filter(Boolean);

    const name = nameCandidates.length > 0
      ? nameCandidates.sort((a, b) => a.length - b.length)[0]
      : "no_name";

    // -------------------------------
    // 2. Icone HTML
    // -------------------------------
    const htmlIcons = [];
    $("link[rel*='icon']").each((_, el) => {
      const href = $(el).attr("href");
      const sizes = $(el).attr("sizes") || "";
      if (href) htmlIcons.push({ href, sizes });
    });

    // -------------------------------
    // 3. Manifest.json
    // -------------------------------
    let manifestIcons = [];
    const manifestHref = $('link[rel="manifest"]').attr("href");

    if (manifestHref) {
      try {
        const manifestUrl = new URL(manifestHref, baseUrl).href;
        const manifestRes = await axios.get(manifestUrl, { timeout: 3000 });
        const manifest = manifestRes.data;

        if (manifest.icons && Array.isArray(manifest.icons)) {
          manifestIcons = manifest.icons.map(icon => ({
            href: icon.src,
            sizes: icon.sizes || ""
          }));
        }
      } catch {}
    }

    // -------------------------------
    // 4. Fallback 4 icone
    // -------------------------------
    const fallbackPaths = [
      "/favicon.ico",
      "/favicon.png",
      "/icon.png",
      "/apple-touch-icon.png"
    ];

    const fallbackIcons = fallbackPaths.map(p => ({
      href: p,
      sizes: ""
    }));

    // -------------------------------
    // 5. Unisci tutte le icone
    // -------------------------------
    const allIcons = [...htmlIcons, ...manifestIcons, ...fallbackIcons];

    // -------------------------------
    // 6. Determina dimensione reale (PNG, ICO, SVG)
    // -------------------------------
    const iconsWithRealSize = [];

    for (const icon of allIcons) {
      try {
        const url = new URL(icon.href, baseUrl).href;
        const imgRes = await axios.get(url, { responseType: "arraybuffer" });

        let width = 0;

        // ---- PNG / JPG / ICO ----
        try {
          const dim = sizeOf(imgRes.data);
          if (dim.width) width = dim.width;
        } catch {
          // Non è un formato supportato da image-size
        }

        // ---- SVG → converti in PNG e misura ----
        if (width === 0) {
          try {
            const pngBuffer = await sharp(imgRes.data).png().toBuffer();
            const dim = sizeOf(pngBuffer);
            if (dim.width) width = dim.width;
          } catch {
            // SVG non convertibile → ignora
          }
        }

        if (width > 0) {
          iconsWithRealSize.push({ url, size: width });
        }

      } catch {
        // icona non accessibile → ignora
      }
    }

    // -------------------------------
    // 7. Scegli la più grande
    // -------------------------------
    iconsWithRealSize.sort((a, b) => b.size - a.size);

    const icon = iconsWithRealSize.length > 0
      ? iconsWithRealSize[0].url
      : null;

    return { name, icon };

  } catch {
    return { name: "no_name", icon: null };
  }
}