/**
 * Renders public/favicon.svg into the raster icons the site links to.
 * Run with `npm run favicons` after changing the logo; outputs are committed,
 * so the build never needs this script.
 */
import { readFile, writeFile } from "node:fs/promises";
import sharp from "sharp";
import pngToIco from "png-to-ico";

const SRC = new URL("../public/favicon.svg", import.meta.url);
const OUT = new URL("../public/", import.meta.url);

// The patch field, so the opaque Apple icon matches the artwork.
const NAVY = "#0e1e2c";

const svg = await readFile(SRC);
const png = (size) =>
  sharp(svg, { density: 300 }).resize(size, size).png().toBuffer();

const [i16, i32, i48] = await Promise.all([png(16), png(32), png(48)]);
await writeFile(new URL("favicon.ico", OUT), await pngToIco([i16, i32, i48]));
await writeFile(new URL("icon-192.png", OUT), await png(192));
await writeFile(new URL("icon-512.png", OUT), await png(512));
// iOS composites its own corner mask and dislikes transparency.
await writeFile(
  new URL("apple-touch-icon.png", OUT),
  await sharp(svg, { density: 300 })
    .resize(180, 180)
    .flatten({ background: NAVY })
    .png()
    .toBuffer(),
);

console.log("favicons written to public/");