@okxweb3/coin-bitcoin
Version:
@okxweb3/coin-bitcoin is a Bitcoin SDK for building Web3 wallets and applications. It supports BTC, BSV, DOGE, LTC, and TBTC, enabling private key management, transaction signing, address generation, and inscriptions like BRC-20, Runes, CAT, and Atomicals
79 lines • 2.52 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.encodingLength = exports.decode = exports.encode = void 0;
const MAX_SAFE_INTEGER = 9007199254740991;
function checkUInt53(n) {
if (n < 0 || n > MAX_SAFE_INTEGER || n % 1 !== 0)
throw new RangeError('value out of range');
}
function encode(_number, buffer, offset) {
checkUInt53(_number);
if (!buffer)
buffer = Buffer.allocUnsafe(encodingLength(_number));
if (!Buffer.isBuffer(buffer))
throw new TypeError('buffer must be a Buffer instance');
if (!offset)
offset = 0;
if (_number < 0xfd) {
buffer.writeUInt8(_number, offset);
Object.assign(encode, { bytes: 1 });
}
else if (_number <= 0xffff) {
buffer.writeUInt8(0xfd, offset);
buffer.writeUInt16LE(_number, offset + 1);
Object.assign(encode, { bytes: 3 });
}
else if (_number <= 0xffffffff) {
buffer.writeUInt8(0xfe, offset);
buffer.writeUInt32LE(_number, offset + 1);
Object.assign(encode, { bytes: 5 });
}
else {
buffer.writeUInt8(0xff, offset);
buffer.writeUInt32LE(_number >>> 0, offset + 1);
buffer.writeUInt32LE((_number / 0x100000000) | 0, offset + 5);
Object.assign(encode, { bytes: 9 });
}
return buffer;
}
exports.encode = encode;
function decode(buffer, offset) {
if (!Buffer.isBuffer(buffer))
throw new TypeError('buffer must be a Buffer instance');
if (!offset)
offset = 0;
const first = buffer.readUInt8(offset);
if (first < 0xfd) {
Object.assign(decode, { bytes: 1 });
return first;
}
else if (first === 0xfd) {
Object.assign(decode, { bytes: 3 });
return buffer.readUInt16LE(offset + 1);
}
else if (first === 0xfe) {
Object.assign(decode, { bytes: 5 });
return buffer.readUInt32LE(offset + 1);
}
else {
Object.assign(decode, { bytes: 9 });
const lo = buffer.readUInt32LE(offset + 1);
const hi = buffer.readUInt32LE(offset + 5);
const _number = hi * 0x0100000000 + lo;
checkUInt53(_number);
return _number;
}
}
exports.decode = decode;
function encodingLength(_number) {
checkUInt53(_number);
return _number < 0xfd
? 1
: _number <= 0xffff
? 3
: _number <= 0xffffffff
? 5
: 9;
}
exports.encodingLength = encodingLength;
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