@vbyte/btc-dev/dist/lib/tx/encode.js

Batteries-included toolset for plebian bitcoin development

import { Buff } from '@vbyte/buff';
import { Assert } from '@vbyte/micro-lib';
import { assert_tx_data } from './validate.js';
import { COINBASE } from '../../const.js';
export function encode_tx(txdata, use_segwit = true) {
    assert_tx_data(txdata);
    const { version, vin, vout, locktime } = txdata;
    const buffer = [encode_tx_version(version)];
    if (use_segwit) {
        buffer.push(Buff.hex('0001'));
    }
    buffer.push(encode_tx_inputs(vin));
    buffer.push(encode_tx_outputs(vout));
    if (use_segwit) {
        for (const input of vin) {
            buffer.push(encode_vin_witness(input.witness));
        }
    }
    buffer.push(encode_tx_locktime(locktime));
    return Buff.join(buffer);
}
export function encode_tx_version(num) {
    return Buff.num(num, 4).reverse();
}
export function encode_txin_txid(txid) {
    return Buff.hex(txid, 32).reverse();
}
export function encode_txin_vout(vout) {
    return Buff.num(vout, 4).reverse();
}
export function encode_txin_sequence(sequence) {
    return Buff.num(sequence, 4).reverse();
}
export function encode_tx_inputs(vin) {
    const raw = [Buff.varint(vin.length, 'le')];
    for (const input of vin) {
        raw.push(encode_vin(input));
    }
    return Buff.join(raw);
}
export function encode_vin(txin) {
    if (txin.coinbase !== null) {
        return Buff.join([
            encode_txin_txid(COINBASE.TXID),
            encode_txin_vout(COINBASE.VOUT),
            encode_script_data(txin.coinbase),
            encode_txin_sequence(txin.sequence)
        ]);
    }
    else {
        return Buff.join([
            encode_txin_txid(txin.txid),
            encode_txin_vout(txin.vout),
            encode_script_data(txin.script_sig),
            encode_txin_sequence(txin.sequence)
        ]);
    }
}
export function encode_vout_value(value) {
    return Buff.big(value, 8).reverse();
}
export function encode_tx_outputs(vout) {
    const buffer = [Buff.varint(vout.length, 'le')];
    for (const output of vout) {
        buffer.push(encode_tx_vout(output));
    }
    return Buff.join(buffer);
}
export function encode_tx_vout(txout) {
    const { value, script_pk } = txout;
    return Buff.join([
        encode_vout_value(value),
        encode_script_data(script_pk)
    ]);
}
export function encode_vin_witness(data) {
    const buffer = [Buff.varint(data.length)];
    for (const param of data) {
        buffer.push(encode_script_data(param));
    }
    return Buff.join(buffer);
}
export function encode_tx_locktime(locktime) {
    return Buff.num(locktime, 4).reverse();
}
export function encode_script_data(script) {
    if (script !== null) {
        Assert.is_hex(script);
        return Buff.hex(script).prefix_varint('le');
    }
    else {
        return Buff.hex('00');
    }
}