// Build the /press/images gallery from the actual files on disk.
//
// Source of truth: public/landing/press/images/
//   *.jpg|png|webp            — photography (the downloadable masters)
//   renders/*.png|webp        — product renders (downloadable masters)
//   previews/                 — GENERATED 960px webp previews (this script)
//
// For every master it (re)generates a preview when missing or stale, then
// returns the gallery <figure> markup + counts for build-pages.mjs to splice
// into press-images.html ({{PRESS_GALLERY_RENDERS}} / {{PRESS_GALLERY_PHOTOS}}
// / {{PRESS_GALLERY_COUNT}}). Captions and the mono meta line (FORMAT · WxH ·
// size) are derived from the file itself, so they stay truthful.
//
// Adding an image to the press kit = drop the master in the right folder with
// a kebab-case name and run `node scripts/build-pages.mjs`. Masters must stay
// under ~25 MB (the Cloudflare Pages per-file limit) — anything bigger goes to
// R2 and gets hand-linked instead.
import fs from "node:fs";
import path from "node:path";
import sharp from "sharp";

const ROOT = "public/landing/press/images";
const RENDERS = path.join(ROOT, "renders");
const PREVIEWS = path.join(ROOT, "previews");
const EXT = /\.(jpe?g|png|webp)$/i;

// kebab-case file name -> display caption
const TOKENS = { ipd: "IPD", ceo: "CEO", vr: "VR" };
const SMALL = new Set(["in", "with", "on", "the", "and", "of", "a", "at", "to"]);
function caption(base) {
  return base
    .split("-")
    .map((w, i) => {
      if (TOKENS[w]) return TOKENS[w];
      if (/^\d/.test(w)) return w;
      if (i > 0 && SMALL.has(w)) return w;
      return w[0].toUpperCase() + w.slice(1);
    })
    .join(" ");
}

function fmtSize(bytes) {
  const kb = bytes / 1024;
  return kb >= 1024 ? (kb / 1024).toFixed(1) + " MB" : Math.round(kb) + " KB";
}

const DL_ICON =
  '<svg viewBox="0 0 16 16" fill="none" stroke="currentColor" stroke-width="1.5" aria-hidden="true"><path d="M8 2v9M4 7.5L8 11l4-3.5M2.5 14h11"/></svg>';

async function buildItem(absFile, urlDir, { fit }) {
  const file = path.basename(absFile);
  const base = file.replace(EXT, "");
  const meta = await sharp(absFile).metadata();
  const stat = fs.statSync(absFile);

  // preview: 960px webp, regenerated only when missing or older than the master
  const prevFile = path.join(PREVIEWS, base + ".webp");
  if (!fs.existsSync(prevFile) || fs.statSync(prevFile).mtimeMs < stat.mtimeMs) {
    await sharp(absFile)
      .resize({ width: 960, withoutEnlargement: true })
      .webp({ quality: 72, effort: 6 })
      .toFile(prevFile);
  }

  const name = caption(base);
  const fmt = path.extname(file).slice(1).toUpperCase().replace("JPG", "JPEG");
  const info = `${fmt} &middot; ${meta.width}&times;${meta.height} &middot; ${fmtSize(stat.size)}`;
  const href = `${urlDir}/${file}`;
  const prev = `/landing/press/images/previews/${base}.webp`;
  const view = fit ? "gal__view gal__view--fit" : "gal__view";

  return `      <figure class="gal" data-rv>
        <a class="${view}" href="${href}" data-box aria-label="View larger: ${name}">
          <img src="${prev}" alt="${name}" width="960" height="600" loading="lazy">
        </a>
        <figcaption class="gal__row">
          <span><span class="gal__name">${name}</span>
          <span class="gal__meta">${info}</span></span>
          <a class="gal__dl" href="${href}" download aria-label="Download: ${name}">
            ${DL_ICON}
          </a>
        </figcaption>
      </figure>`;
}

export async function buildPressGallery() {
  fs.mkdirSync(PREVIEWS, { recursive: true });

  const photos = fs.readdirSync(ROOT).filter((f) => EXT.test(f)).sort();
  const renders = fs.readdirSync(RENDERS).filter((f) => EXT.test(f)).sort();

  // prune previews whose master is gone (renamed/removed files)
  const live = new Set([...photos, ...renders].map((f) => f.replace(EXT, "") + ".webp"));
  for (const p of fs.readdirSync(PREVIEWS))
    if (!live.has(p)) fs.unlinkSync(path.join(PREVIEWS, p));

  const photoHtml = [];
  for (const f of photos)
    photoHtml.push(await buildItem(path.join(ROOT, f), "/landing/press/images", { fit: false }));
  const renderHtml = [];
  for (const f of renders)
    renderHtml.push(await buildItem(path.join(RENDERS, f), "/landing/press/images/renders", { fit: true }));

  console.log(`press gallery: ${renders.length} renders + ${photos.length} photos (previews in ${PREVIEWS})`);
  return {
    renders: renderHtml.join("\n\n"),
    photos: photoHtml.join("\n\n"),
  };
}