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crate::ix!();
#[derive(Default)]
pub struct PrecomputedTransactionData {
/**
| BIP341 precomputed data.
|
| These are single-SHA256,
| see https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki#cite_note-15.
|
*/
prevouts_single_hash: u256,
sequences_single_hash: u256,
outputs_single_hash: u256,
spent_amounts_single_hash: u256,
spent_scripts_single_hash: u256,
/**
| Whether the 5 fields above are initialized.
|
*/
bip341_taproot_ready: bool, // default = false
/**
| BIP143 precomputed data (double-SHA256).
|
*/
hash_prevouts: u256,
/**
| BIP143 precomputed data (double-SHA256).
|
*/
hash_sequence: u256,
/**
| BIP143 precomputed data (double-SHA256).
|
*/
hash_outputs: u256,
/**
| Whether the 3 fields above are initialized.
|
*/
bip143_segwit_ready: bool, // default = false
spent_outputs: Vec<TxOut>,
/**
| Whether m_spent_outputs is initialized.
|
*/
spent_outputs_ready: bool, // default = false
}
impl PrecomputedTransactionData {
/**
| Initialize this PrecomputedTransactionData
| with transaction data.
|
| -----------
| @param[in] tx
|
| The transaction for which data is being
| precomputed.
| ----------
| @param[in] spent_outputs
|
| The CTxOuts being spent, one for each
| tx.vin, in order.
| ----------
| @param[in] force
|
| Whether to precompute data for all optional
| features, regardless of what is in the
| inputs (used at signing time, when the
| inputs aren't filled in yet).
|
*/
pub fn init<T>(&mut self,
tx_to: &T,
spent_outputs: Vec<TxOut>,
force: Option<bool>) {
let force: bool = force.unwrap_or(false);
todo!();
/*
assert(!m_spent_outputs_ready);
m_spent_outputs = std::move(spent_outputs);
if (!m_spent_outputs.empty()) {
assert(m_spent_outputs.size() == txTo.vin.size());
m_spent_outputs_ready = true;
}
// Determine which precomputation-impacting features this transaction uses.
bool uses_bip143_segwit = force;
bool uses_bip341_taproot = force;
for (size_t inpos = 0; inpos < txTo.vin.size() && !(uses_bip143_segwit && uses_bip341_taproot); ++inpos) {
if (!txTo.vin[inpos].scriptWitness.IsNull()) {
if (m_spent_outputs_ready && m_spent_outputs[inpos].scriptPubKey.size() == 2 + WITNESS_V1_TAPROOT_SIZE &&
m_spent_outputs[inpos].scriptPubKey[0] == OP_1) {
// Treat every witness-bearing spend with 34-byte scriptPubKey that starts with OP_1 as a Taproot
// spend. This only works if spent_outputs was provided as well, but if it wasn't, actual validation
// will fail anyway. Note that this branch may trigger for scriptPubKeys that aren't actually segwit
// but in that case validation will fail as SCRIPT_ERR_WITNESS_UNEXPECTED anyway.
uses_bip341_taproot = true;
} else {
// Treat every spend that's not known to native witness v1 as a Witness v0 spend. This branch may
// also be taken for unknown witness versions, but it is harmless, and being precise would require
// P2SH evaluation to find the redeemScript.
uses_bip143_segwit = true;
}
}
if (uses_bip341_taproot && uses_bip143_segwit) break; // No need to scan further if we already need all.
}
if (uses_bip143_segwit || uses_bip341_taproot) {
// Computations shared between both sighash schemes.
m_prevouts_single_hash = GetPrevoutsSHA256(txTo);
m_sequences_single_hash = GetSequencesSHA256(txTo);
m_outputs_single_hash = GetOutputsSHA256(txTo);
}
if (uses_bip143_segwit) {
hashPrevouts = SHA256Uint256(m_prevouts_single_hash);
hashSequence = SHA256Uint256(m_sequences_single_hash);
hashOutputs = SHA256Uint256(m_outputs_single_hash);
m_bip143_segwit_ready = true;
}
if (uses_bip341_taproot) {
m_spent_amounts_single_hash = GetSpentAmountsSHA256(m_spent_outputs);
m_spent_scripts_single_hash = GetSpentScriptsSHA256(m_spent_outputs);
m_bip341_taproot_ready = true;
}
*/
}
pub fn new<T>(tx_to: &T) -> Self {
todo!();
/*
Init(txTo, {});
*/
}
}