qrmanual

qrmanual is a TypeScript library for generating fully programmatic QR Codes conforming to Version 2 - Level L (25×25 modules, low error correction) without any external dependencies.

🚀 Features

• Byte Mode (UTF-8) encoding with terminator and padding handling
• Data and ECC (10 bytes) codewords generation via Reed–Solomon over Galois Field GF(256)
• Construction of a 25×25 matrix with Finder Patterns, Alignment Pattern, Timing Pattern, Format Information and application of Mask 0
• Direct scalable SVG output
• Modular API: import only what you need (encoder, matrix, svg)

📦 Installation

Install via npm or Yarn:

npm install qrmanual
# or
yarn add qrmanual

💡 Usage Examples

Node.js (CommonJS)

const { generateQRCodeSVG } = require('qrmanual');
const fs = require('fs');

const payload = 'https://example.com';
const svg = generateQRCodeSVG(payload);

fs.writeFileSync('qr.svg', svg, 'utf8');
console.log('QR Code saved to qr.svg');

TypeScript (ES Modules)

import { generateQRCodeSVG } from 'qrmanual';
import { writeFileSync } from 'fs';

const svg = generateQRCodeSVG('Hello, world!');
writeFileSync('qr.svg', svg, 'utf8');
console.log('QR Code generated: qr.svg');

Browser (ES Modules)

<div id="qr"></div>
<script type="module">
  import { generateQRCodeSVG } from 'qrmanual';
  document.getElementById('qr').innerHTML = generateQRCodeSVG('https://example.com');
</script>

🛠️ API Reference

| Function | Signature | Description | | -------------------------- | ------------------------------------------------ | ----------------------------------------------------------------- | | encodePayloadToCodewords | (payload: string) => number[] | Returns 44 codewords (34 data + 10 ECC) for the given text | | buildMatrix | (codewords: number[]) => (0\|1)[][] | Builds the 25×25 matrix of modules (0 = white, 1 = black) | | renderSVG | (matrix: (0\|1)[][], scale?: number) => string | Converts a matrix to an SVG string. Adjust scale as needed. | | generateQRCodeSVG | (payload: string) => string | Full pipeline: encodes, builds matrix, and returns SVG |

Default mask: always uses Mask 0. To support other masks or error levels, please modify the modules or submit a PR.

🤝 Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository
2. git clone https://github.com/kauecavalcante/qrmanual.git
3. npm install
4. npm run build to compile
5. npm test to run tests
6. Open a Pull Request with your changes

Check CONTRIBUTING.md for detailed guidelines.

📄 License

This project is licensed under the MIT License.