const fs = require('fs');
const path = require('path');

// Minimal valid 1x1 red PNG (base64) - scaled up to requested sizes via simple pixel repetition
// For a real extension build, we just need valid PNG files. Chrome won't validate content during build.
// We'll create minimal valid PNG files.

function createSolidColorPNG(width, height, r, g, b) {
  // PNG signature
  const signature = Buffer.from([0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A]);
  
  // Helper: create PNG chunk
  function makeChunk(type, data) {
    const typeBuf = Buffer.from(type, 'ascii');
    const lenBuf = Buffer.alloc(4);
    lenBuf.writeUInt32BE(data.length, 0);
    const crc = require('zlib').crc32(Buffer.concat([typeBuf, data]));
    const crcBuf = Buffer.alloc(4);
    crcBuf.writeUInt32BE(crc, 0);
    return Buffer.concat([lenBuf, typeBuf, data, crcBuf]);
  }
  
  // IHDR chunk
  const ihdr = Buffer.alloc(13);
  ihdr.writeUInt32BE(width, 0);
  ihdr.writeUInt32BE(height, 4);
  ihdr[8] = 8; // bit depth
  ihdr[9] = 2; // color type RGB
  ihdr[10] = 0; // compression
  ihdr[11] = 0; // filter method
  ihdr[12] = 0; // interlace
  
  // IDAT chunk - raw image data: filter byte + RGB pixels per row
  const rowSize = 1 + width * 3;
  const rawData = Buffer.alloc(height * rowSize);
  for (let y = 0; y < height; y++) {
    rawData[y * rowSize] = 0; // filter byte: none
    for (let x = 0; x < width; x++) {
      rawData[y * rowSize + 1 + x * 3] = r;
      rawData[y * rowSize + 1 + x * 3 + 1] = g;
      rawData[y * rowSize + 1 + x * 3 + 2] = b;
    }
  }
  
  const compressed = require('zlib').deflateSync(rawData);
  
  // IEND chunk
  const iend = makeChunk('IEND', Buffer.alloc(0));
  
  return Buffer.concat([
    signature,
    makeChunk('IHDR', ihdr),
    makeChunk('IDAT', compressed),
    iend
  ]);
}

const outDir = path.join(__dirname, 'icons');
fs.mkdirSync(outDir, { recursive: true });

fs.writeFileSync(path.join(outDir, 'icon16.png'), createSolidColorPNG(16, 16, 239, 68, 68));
fs.writeFileSync(path.join(outDir, 'icon48.png'), createSolidColorPNG(48, 48, 239, 68, 68));
fs.writeFileSync(path.join(outDir, 'icon128.png'), createSolidColorPNG(128, 128, 239, 68, 68));

console.log('Icons generated successfully');