chore: add topic candidates for 2026-04-25

gen-png.cjs

@@ -0,0 +1,97 @@
+// Pure JS PNG Generator for QR codes
+// Write a minimal valid PNG with no external dependencies
+const fs = require('fs');
+const zlib = require('zlib');
+
+function crc32(buf) {
+  let crc = 0xFFFFFFFF;
+  const table = new Uint32Array(256);
+  for (let i = 0; i < 256; i++) {
+    let c = i;
+    for (let k = 0; k < 8; k++) c = (c & 1) ? 0xEDB88320 ^ (c >>> 1) : c >>> 1;
+    table[i] = c;
+  }
+  for (let i = 0; i < buf.length; i++) crc = table[(crc ^ buf[i]) & 0xFF] ^ (crc >>> 8);
+  return (crc ^ 0xFFFFFFFF) >>> 0;
+}
+
+function makeChunk(type, data) {
+  const typeB = Buffer.from(type);
+  const lenB = Buffer.alloc(4);
+  lenB.writeUInt32BE(data.length);
+  const crcB = Buffer.alloc(4);
+  crcB.writeUInt32BE(crc32(Buffer.concat([typeB, data])));
+  return Buffer.concat([lenB, typeB, data, crcB]);
+}
+
+function createPNG(matrix) {
+  const size = matrix.length;
+  const scale = 10;
+  const outSize = size * scale;
+  
+  // Raw image data: filter byte (0) + RGB pixels per row
+  const raw = Buffer.alloc((1 + size * 3) * outSize);
+  for (let y = 0; y < outSize; y++) {
+    const rowOffset = y * (1 + outSize * 3);
+    raw[rowOffset] = 0; // filter type: none
+    const moduleY = Math.floor(y / scale);
+    for (let x = 0; x < outSize; x++) {
+      const moduleX = Math.floor(x / scale);
+      const pixel = matrix[moduleY][moduleX] ? 0 : 255;
+      const offset = rowOffset + 1 + x * 3;
+      raw[offset] = pixel;     // R
+      raw[offset + 1] = pixel; // G
+      raw[offset + 2] = pixel; // B
+    }
+  }
+  
+  const compressed = zlib.deflateSync(raw);
+  
+  // PNG signature
+  const signature = Buffer.from([0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A]);
+  
+  // IHDR chunk
+  const ihdr = Buffer.alloc(13);
+  ihdr.writeUInt32BE(outSize, 0);  // width
+  ihdr.writeUInt32BE(outSize, 4);  // height
+  ihdr[8] = 8;  // bit depth
+  ihdr[9] = 2;  // color type (RGB)
+  ihdr[10] = 0; // compression
+  ihdr[11] = 0; // filter
+  ihdr[12] = 0; // interlace
+  
+  const ihdrChunk = makeChunk('IHDR', ihdr);
+  const idatChunk = makeChunk('IDAT', compressed);
+  const iendChunk = makeChunk('IEND', Buffer.alloc(0));
+  
+  return Buffer.concat([signature, ihdrChunk, idatChunk, iendChunk]);
+}
+
+// Matrix from our QR generator (21x21 for "TEST")
+const matrix = [
+  [1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1],
+  [1,0,0,0,0,0,1,0,1,0,1,0,1,0,1,0,0,0,0,0,1],
+  [1,0,1,1,1,0,1,0,1,1,0,1,0,1,0,1,1,1,0,0,1],
+  [1,0,1,1,1,0,1,0,0,1,1,0,1,0,1,0,1,1,1,0,1],
+  [1,0,1,1,1,0,1,0,1,0,1,0,0,1,0,1,1,1,0,0,1],
+  [1,0,0,0,0,0,1,0,1,1,0,1,1,1,1,1,0,0,0,0,1],
+  [1,1,1,1,1,1,1,0,0,0,0,0,1,0,1,1,1,1,1,1,1],
+  [0,0,0,0,0,0,0,0,1,0,1,0,1,0,0,0,0,0,0,0,0],
+  [1,0,1,0,1,0,1,0,0,0,1,1,0,1,0,1,0,1,1,0,1],
+  [0,1,0,1,0,1,0,1,1,0,0,1,0,1,0,1,1,0,0,1,0],
+  [0,0,1,0,0,1,0,1,0,1,0,1,0,1,0,0,1,0,0,0,0],
+  [1,1,0,1,0,0,1,0,1,0,1,0,1,0,1,1,0,1,1,1,1],
+  [0,0,0,1,1,1,0,1,0,1,0,1,0,1,1,0,1,1,0,0,0],
+  [1,1,1,0,0,0,1,0,0,0,1,0,0,1,0,1,1,0,1,1,0],
+  [1,0,1,1,1,0,1,0,1,1,0,1,0,1,0,0,0,0,0,1,0],
+  [1,0,0,0,0,0,1,0,0,1,1,0,1,0,1,1,1,0,1,0,1],
+  [1,1,1,1,1,1,1,0,1,0,1,0,1,1,0,1,0,1,0,0,1],
+  [0,0,0,0,0,0,0,0,1,0,1,1,0,1,0,1,1,0,1,1,0],
+  [1,1,1,1,1,1,1,0,0,1,0,1,0,0,0,1,1,0,0,0,0],
+  [1,0,0,0,0,0,1,0,1,0,1,0,1,0,1,1,0,1,1,1,1],
+  [1,1,1,1,1,1,1,0,1,0,1,1,0,0,1,0,0,0,0,0,0],
+];
+
+const png = createPNG(matrix);
+fs.writeFileSync('/home/node/.openclaw/workspace/assets/qr-test.png', png);
+console.log('PNG written:', png.length, 'bytes');