/**
* build inputs and outputs lists for TransactionBuilder
*
* @param TransactionBuilder $txBuilder
* @return array
* @throws \Exception
*/
public function buildTx(TransactionBuilder $txBuilder)
{
$send = $txBuilder->getOutputs();
$utxos = $txBuilder->getUtxos();
foreach ($utxos as $utxo) {
if (!$utxo->address || !$utxo->value || !$utxo->scriptPubKeyHex) {
$tx = $this->sdk->transaction($utxo->hash);
if (!$tx || !isset($tx['outputs'][$utxo->index])) {
throw new \Exception("Invalid output [{$utxo->hash}][{$utxo->index}]");
}
$output = $tx['outputs'][$utxo->index];
if (!$utxo->address) {
$utxo->address = $output['address'];
}
if (!$utxo->value) {
$utxo->value = $output['value'];
}
if (!$utxo->scriptPubKeyHex) {
$utxo->scriptPubKeyHex = $output['script_hex'];
}
}
if (!$utxo->path) {
$address = $utxo->address;
if (!BitcoinLib::validate_address($address)) {
throw new \Exception("Invalid address [{$address}]");
}
$utxo->path = $this->getPathForAddress($address);
}
if (!$utxo->redeemScript) {
list(, $redeemScript) = $this->getRedeemScriptByPath($utxo->path);
$utxo->redeemScript = $redeemScript;
}
}
if (array_sum(array_map(function (UTXO $utxo) {
return $utxo->value;
}, $utxos)) < array_sum(array_column($send, 'value'))) {
throw new \Exception("Atempting to spend more than sum of UTXOs");
}
list($fee, $change) = $this->determineFeeAndChange($txBuilder);
if ($txBuilder->getValidateChange() !== null && $txBuilder->getValidateChange() != $change) {
throw new \Exception("the amount of change suggested by the coin selection seems incorrect");
}
if ($txBuilder->getValidateFee() !== null && $txBuilder->getValidateFee() != $fee) {
throw new \Exception("the fee suggested by the coin selection ({$txBuilder->getValidateFee()}) seems incorrect ({$fee})");
}
if ($change > 0) {
$send[] = ['address' => $txBuilder->getChangeAddress() ?: $this->getNewAddress(), 'value' => $change];
}
// create raw transaction
$inputs = array_map(function (UTXO $utxo) {
return ['txid' => $utxo->hash, 'vout' => (int) $utxo->index, 'address' => $utxo->address, 'scriptPubKey' => $utxo->scriptPubKeyHex, 'value' => $utxo->value, 'path' => $utxo->path, 'redeemScript' => $utxo->redeemScript];
}, $utxos);
// outputs should be randomized to make the change harder to detect
if ($txBuilder->shouldRandomizeChangeOuput()) {
shuffle($send);
}
return [$inputs, $send];
}
