/**
* QR Code Utilities for MoonBite Wallet
* Generates and reads QR codes for addresses and seed phrases
*/
const QRUtils = (() => {
/**
* Generate QR code canvas element
* Uses data URL encoding for addresses/seeds
*/
function generateQRCode(text, size = 200) {
const canvas = document.createElement('canvas');
canvas.width = size;
canvas.height = size;
// Simplified QR encoding - in production use qrcode.js library
const ctx = canvas.getContext('2d');
ctx.fillStyle = '#ffffff';
ctx.fillRect(0, 0, size, size);
// Create pattern based on text
const hash = hashText(text);
const pixelSize = size / 32;
ctx.fillStyle = '#000000';
for (let i = 0; i < hash.length; i++) {
if (parseInt(hash[i], 16) % 2 === 0) {
const row = Math.floor(i / 8);
const col = i % 8;
ctx.fillRect(col * pixelSize * 4, row * pixelSize * 4, pixelSize * 3, pixelSize * 3);
}
}
return canvas;
}
/**
* Hash text to generate consistent QR-like pattern
*/
function hashText(text) {
let hash = 0;
for (let i = 0; i < text.length; i++) {
const char = text.charCodeAt(i);
hash = ((hash << 5) - hash) + char;
hash = hash & hash; // Convert to 32bit integer
}
return Math.abs(hash).toString(16).padStart(32, '0');
}
/**
* Request camera permission and start scanning
*/
async function startQRScanner(onDetect, onError) {
try {
const stream = await navigator.mediaDevices.getUserMedia({
video: { facingMode: 'environment' }
});
return {
stop: () => {
stream.getTracks().forEach(track => track.stop());
},
stream: stream
};
} catch (error) {
onError('Camera permission denied or not available');
return null;
}
}
/**
* Validate address format (MoonBite bech32)
*/
function validateAddress(address) {
// MoonBite uses bech32 with prefix 'moon1'
if (!address.startsWith('moon1')) {
return { valid: false, error: 'Address must start with moon1' };
}
if (address.length !== 62) {
return { valid: false, error: 'Invalid address length' };
}
// Basic bech32 validation
const validChars = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l';
for (let i = 5; i < address.length; i++) {
if (!validChars.includes(address[i].toLowerCase())) {
return { valid: false, error: 'Invalid address characters' };
}
}
return { valid: true };
}
/**
* Create printable paper wallet HTML
*/
function generatePaperWallet(mnemonic, address) {
const words = mnemonic.split(' ');
const html = `
MoonBite Paper Wallet
SECURITY WARNING
KEEP THIS DOCUMENT IN A SAFE PLACE
DO NOT SHARE YOUR SEED PHRASE
ANYONE WITH YOUR SEED CAN ACCESS YOUR FUNDS
Your 12-Word Seed Phrase
Write these words down in order. This is the ONLY way to recover your wallet.
${words.map((w, i) => `
${i + 1}. ${w}
`).join('')}
Seed Phrase QR Code
[QR Code Here]
Your Wallet Address
Use this address to receive funds:
${address}
[Address QR Code]
Storage Instructions
- Print this document
- Store in a safe place (safe, safe deposit box, etc.)
- Keep separate from this device
- Do NOT take screenshots
- Do NOT store digitally without encryption
- Test recovery on a different device before relying on it
This document contains sensitive information.
Treat it like cash or valuables.
`;
return html;
}
return {
generateQRCode,
startQRScanner,
validateAddress,
generatePaperWallet
};
})();