// Генерация PWA-иконок «Премиум Водитель» без сторонних либ (zlib PNG-энкодер).
// Дизайн: кремовый фон #F3EEE3, тёмная скруглённая плитка #1C1B19,
// внутри белая «карта» #F6F2E9 с тёмной полосой (финансовый мотив). Без жёлтого/текста.
import zlib from "node:zlib";
import fs from "node:fs";
import path from "node:path";

const CREAM = [243, 238, 227];
const INK = [28, 27, 25];
const CARD = [246, 242, 233];

function crc32(buf) {
  let c = ~0;
  for (let i = 0; i < buf.length; i++) {
    c ^= buf[i];
    for (let k = 0; k < 8; k++) c = (c >>> 1) ^ (0xedb88320 & -(c & 1));
  }
  return (~c) >>> 0;
}
function chunk(type, data) {
  const t = Buffer.from(type, "ascii");
  const len = Buffer.alloc(4); len.writeUInt32BE(data.length, 0);
  const body = Buffer.concat([t, data]);
  const crc = Buffer.alloc(4); crc.writeUInt32BE(crc32(body), 0);
  return Buffer.concat([len, body, crc]);
}
function encodePng(N, rgba) {
  const sig = Buffer.from([137, 80, 78, 71, 13, 10, 26, 10]);
  const ihdr = Buffer.alloc(13);
  ihdr.writeUInt32BE(N, 0); ihdr.writeUInt32BE(N, 4); ihdr[8] = 8; ihdr[9] = 6;
  const stride = N * 4;
  const raw = Buffer.alloc(N * (stride + 1));
  for (let y = 0; y < N; y++) {
    raw[y * (stride + 1)] = 0;
    rgba.copy(raw, y * (stride + 1) + 1, y * stride, y * stride + stride);
  }
  return Buffer.concat([sig, chunk("IHDR", ihdr), chunk("IDAT", zlib.deflateSync(raw)), chunk("IEND", Buffer.alloc(0))]);
}
function inRoundRect(px, py, x0, y0, x1, y1, r) {
  if (px < x0 || px >= x1 || py < y0 || py >= y1) return false;
  const cx = px < x0 + r ? x0 + r : px >= x1 - r ? x1 - r : px;
  const cy = py < y0 + r ? y0 + r : py >= y1 - r ? y1 - r : py;
  const dx = px - cx, dy = py - cy;
  return dx * dx + dy * dy <= r * r;
}

function draw(N) {
  const buf = Buffer.alloc(N * N * 4);
  // tile (centered ~64%)
  const tile = Math.round(N * 0.64), tx0 = Math.round((N - tile) / 2), ty0 = tx0;
  const tx1 = tx0 + tile, ty1 = ty0 + tile, tr = Math.round(tile * 0.24);
  // card inside tile
  const cw = Math.round(tile * 0.62), ch = Math.round(tile * 0.42);
  const cx0 = Math.round((N - cw) / 2), cy0 = Math.round((N - ch) / 2);
  const cx1 = cx0 + cw, cy1 = cy0 + ch, cr = Math.round(ch * 0.18);
  // stripe near top of card
  const sy0 = cy0 + Math.round(ch * 0.22), sy1 = sy0 + Math.round(ch * 0.14);
  for (let y = 0; y < N; y++) {
    for (let x = 0; x < N; x++) {
      let col = CREAM;
      if (inRoundRect(x, y, tx0, ty0, tx1, ty1, tr)) col = INK;
      if (inRoundRect(x, y, cx0, cy0, cx1, cy1, cr)) col = CARD;
      if (x >= cx0 && x < cx1 && y >= sy0 && y < sy1) col = INK;
      const o = (y * N + x) * 4;
      buf[o] = col[0]; buf[o + 1] = col[1]; buf[o + 2] = col[2]; buf[o + 3] = 255;
    }
  }
  return encodePng(N, buf);
}

const dir = path.resolve("public/icons");
fs.mkdirSync(dir, { recursive: true });
for (const N of [192, 512]) {
  fs.writeFileSync(path.join(dir, `icon-${N}.png`), draw(N));
  console.log(`wrote icon-${N}.png`);
}