job_creator.rs

//! The job creator module provides logic to create extended mining jobs given a template from
//! a template provider as well as logic to clean up old templates when new blocks are mined
use crate::{errors, utils::Id, Error};
use binary_sv2::B064K;
use mining_sv2::NewExtendedMiningJob;
use nohash_hasher::BuildNoHashHasher;
use std::{collections::HashMap, convert::TryInto};
use template_distribution_sv2::{NewTemplate, SetNewPrevHash};
use tracing::debug;

use stratum_common::{
    bitcoin,
    bitcoin::{
        blockdata::{
            transaction::{OutPoint, Transaction, TxIn, TxOut},
            witness::Witness,
        },
        consensus::Decodable,
        util::psbt::serialize::{Deserialize, Serialize},
    },
};

#[derive(Debug)]
pub struct JobsCreators {
    lasts_new_template: Vec<NewTemplate<'static>>,
    job_to_template_id: HashMap<u32, u64, BuildNoHashHasher<u32>>,
    templte_to_job_id: HashMap<u64, u32, BuildNoHashHasher<u64>>,
    ids: Id,
    last_target: mining_sv2::Target,
    extranonce_len: u8,
}

/// Transform the byte array `coinbase_outputs` in a vector of TxOut
/// It assumes the data to be valid data and does not do any kind of check
pub fn tx_outputs_to_costum_scripts(tx_outputs: &[u8]) -> Vec<TxOut> {
    let mut txs = vec![];
    let mut cursor = 0;
    let mut txouts = &tx_outputs[cursor..];
    while let Ok(out) = TxOut::consensus_decode(&mut txouts) {
        let len = match out.script_pubkey.len() {
            a @ 0..=252 => 8 + 1 + a,
            a @ 253..=10000 => 8 + 3 + a,
            _ => break,
        };
        cursor += len;
        txs.push(out)
    }
    txs
}

impl JobsCreators {
    pub fn new(extranonce_len: u8) -> Self {
        Self {
            lasts_new_template: Vec::new(),
            job_to_template_id: HashMap::with_hasher(BuildNoHashHasher::default()),
            templte_to_job_id: HashMap::with_hasher(BuildNoHashHasher::default()),
            ids: Id::new(),
            last_target: mining_sv2::Target::new(0, 0),
            extranonce_len,
        }
    }

    pub fn get_template_id_from_job(&self, job_id: u32) -> Option<u64> {
        self.job_to_template_id.get(&job_id).map(|x| x - 1)
    }

    /// used to create new jobs when a new template arrives
    pub fn on_new_template(
        &mut self,
        template: &mut NewTemplate,
        version_rolling_allowed: bool,
        mut pool_coinbase_outputs: Vec<TxOut>,
        additional_coinbase_script_data_len: u8,
    ) -> Result<NewExtendedMiningJob<'static>, Error> {
        let server_tx_outputs = template.coinbase_tx_outputs.to_vec();
        let mut outputs = tx_outputs_to_costum_scripts(&server_tx_outputs);
        pool_coinbase_outputs.append(&mut outputs);

        // This is to make sure that 0 is never used, so we can use 0 for
        // set_new_prev_hashes that do not refer to any future job/template if needed
        // Then we will do the inverse (-1) where needed
        let template_id = template.template_id + 1;
        self.lasts_new_template.push(template.as_static());
        let next_job_id = self.ids.next();
        self.job_to_template_id.insert(next_job_id, template_id);
        self.templte_to_job_id.insert(template_id, next_job_id);
        new_extended_job(
            template,
            &mut pool_coinbase_outputs,
            additional_coinbase_script_data_len,
            next_job_id,
            version_rolling_allowed,
            self.extranonce_len,
        )
    }

    pub(crate) fn reset_new_templates(&mut self, template: Option<NewTemplate<'static>>) {
        match template {
            Some(t) => self.lasts_new_template = vec![t],
            None => self.lasts_new_template = vec![],
        }
    }

    /// When we get a new `SetNewPrevHash` we need to clear all the other templates and only
    /// keep the one that matches the template_id of the new prev hash. If none match then
    /// we clear all the saved templates.
    pub fn on_new_prev_hash(&mut self, prev_hash: &SetNewPrevHash<'static>) -> Option<u32> {
        self.last_target = prev_hash.target.clone().into();
        let template: Vec<NewTemplate<'static>> = self
            .lasts_new_template
            .clone()
            .into_iter()
            .filter(|a| a.template_id == prev_hash.template_id)
            .collect();
        match template.len() {
            0 => {
                self.reset_new_templates(None);
                None
            }
            1 => {
                self.reset_new_templates(Some(template[0].clone()));

                self.templte_to_job_id
                    .get(&(prev_hash.template_id + 1))
                    .copied()
            }
            // TODO how many templates can we have at max
            _ => todo!("{:#?}", template.len()),
        }
    }

    /// returns the latest mining target
    pub fn last_target(&self) -> mining_sv2::Target {
        self.last_target.clone()
    }
}

pub fn extended_job_from_custom_job(
    referenced_job: &mining_sv2::SetCustomMiningJob,
    additional_coinbase_script_data_len: u8,
    extranonce_len: u8,
) -> Result<NewExtendedMiningJob<'static>, Error> {
    let mut outputs =
        tx_outputs_to_costum_scripts(referenced_job.coinbase_tx_outputs.clone().as_ref());
    let mut template = NewTemplate {
        template_id: 0,
        future_template: false,
        version: referenced_job.version,
        coinbase_tx_version: referenced_job.coinbase_tx_version,
        coinbase_prefix: referenced_job.coinbase_prefix.clone(),
        coinbase_tx_input_sequence: referenced_job.coinbase_tx_input_n_sequence,
        coinbase_tx_value_remaining: referenced_job.coinbase_tx_value_remaining,
        coinbase_tx_outputs_count: outputs.len() as u32,
        coinbase_tx_outputs: referenced_job.coinbase_tx_outputs.clone(),
        coinbase_tx_locktime: referenced_job.coinbase_tx_locktime,
        merkle_path: referenced_job.merkle_path.clone(),
    };
    new_extended_job(
        &mut template,
        &mut outputs,
        additional_coinbase_script_data_len,
        0,
        true,
        extranonce_len,
    )
}

/// returns an extended job given the provided template from the Template Provider and other
/// Pool role related fields.
///
/// Pool related arguments:
///
/// * `coinbase_outputs`: coinbase output transactions specified by the pool.
/// * `job_id`: incremented job identifier specified by the pool.
/// * `version_rolling_allowed`: boolean specified by the channel.
/// * `extranonce_len`: extranonce length specified by the channel.
fn new_extended_job(
    new_template: &mut NewTemplate,
    coinbase_outputs: &mut [TxOut],
    additional_coinbase_script_data_len: u8,
    job_id: u32,
    version_rolling_allowed: bool,
    extranonce_len: u8,
) -> Result<NewExtendedMiningJob<'static>, Error> {
    coinbase_outputs[0].value = match new_template.coinbase_tx_value_remaining.checked_mul(1) {
        //check that value_remaining is updated by TP
        Some(result) => result,
        None => return Err(Error::ValueRemainingNotUpdated),
    };
    let tx_version = new_template
        .coinbase_tx_version
        .try_into()
        .map_err(|_| Error::TxVersionTooBig)?;

    let bip34_bytes = get_bip_34_bytes(new_template, tx_version)?;
    let script_prefix_len = bip34_bytes.len();

    let coinbase = coinbase(
        bip34_bytes,
        tx_version,
        new_template.coinbase_tx_locktime,
        new_template.coinbase_tx_input_sequence,
        coinbase_outputs,
        additional_coinbase_script_data_len,
        extranonce_len,
    );

    let min_ntime = match new_template.future_template {
        true => binary_sv2::Sv2Option::new(None),
        false => {
            let now = std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap()
                .as_secs() as u32;
            binary_sv2::Sv2Option::new(Some(now))
        }
    };

    let new_extended_mining_job: NewExtendedMiningJob<'static> = NewExtendedMiningJob {
        channel_id: 0,
        job_id,
        min_ntime,
        version: new_template.version,
        version_rolling_allowed,
        merkle_path: new_template.merkle_path.clone().into_static(),
        coinbase_tx_prefix: coinbase_tx_prefix(&coinbase, script_prefix_len)?,
        coinbase_tx_suffix: coinbase_tx_suffix(
            &coinbase,
            extranonce_len,
            script_prefix_len,
            additional_coinbase_script_data_len as usize,
        )?,
    };

    debug!(
        "New extended mining job created: {:?}",
        new_extended_mining_job
    );
    Ok(new_extended_mining_job)
}

/// used to extract the coinbase transaction prefix for extended jobs
/// so the extranonce search space can be introduced
fn coinbase_tx_prefix(
    coinbase: &Transaction,
    script_prefix_len: usize,
) -> Result<B064K<'static>, Error> {
    let encoded = coinbase.serialize();
    // If script_prefix_len is not 0 we are not in a test environment and the coinbase will have the
    // 0 witness
    let segwit_bytes = match script_prefix_len {
        0 => 0,
        _ => 2,
    };
    let index = 4    // tx version
        + segwit_bytes
        + 1  // number of inputs (always 1)
        + 32 // prev OutPoint
        + 4  // index
        + 1  // bytes in script (max 100 so always 1 byte)
        + script_prefix_len; // bip34_bytes
    let r = encoded[0..index].to_vec();
    r.try_into().map_err(Error::BinarySv2Error)
}

/// used to extract the coinbase transaction suffix for extended jobs
/// so the extranonce search space can be introduced
fn coinbase_tx_suffix(
    coinbase: &Transaction,
    extranonce_len: u8,
    script_prefix_len: usize,
    additional_coinbase_script_data_len: usize,
) -> Result<B064K<'static>, Error> {
    let encoded = coinbase.serialize();
    // If script_prefix_len is not 0 we are not in a test enviornment and the coinbase have the 0
    // witness
    let segwit_bytes = match script_prefix_len {
        0 => 0,
        _ => 2,
    };
    let r = encoded[4    // tx version
        + segwit_bytes
        + 1  // number of inputs TODO can be also 3
        + 32 // prev OutPoint
        + 4  // index
        + 1  // bytes in script TODO can be also 3
        + script_prefix_len  // bip34_bytes
        + additional_coinbase_script_data_len
        + (extranonce_len as usize)..]
        .to_vec();
    r.try_into().map_err(Error::BinarySv2Error)
}

// Just double check if received coinbase_prefix is the right one can be removed or used only for
// tests
fn get_bip_34_bytes(new_template: &NewTemplate, tx_version: i32) -> Result<Vec<u8>, Error> {
    #[cfg(test)]
    if tx_version == 1 {
        return Ok(vec![]);
    };

    let script_prefix = &new_template.coinbase_prefix.to_vec()[..];

    // Is ok to panic here cause condition will be always true when not in a test chain
    // (regtest ecc ecc)
    #[cfg(not(test))]
    assert!(
        script_prefix.len() > 2,
        "Bitcoin blockchain should be at least 16 block long"
    );

    // Txs version lower or equal to 1 are not allowed in new blocks we need it only to test the
    // JobCreator against old bitcoin blocks
    #[cfg(not(test))]
    if tx_version <= 1 {
        return Err(Error::TxVersionTooLow);
    };

    // add 1 cause 0 is push 1 2 is 1 is push 2 ecc ecc
    // add 1 cause in the len there is also the op code itself
    let bip34_len = script_prefix[0] as usize + 2;
    if bip34_len == script_prefix.len() {
        Ok(script_prefix[0..bip34_len].to_vec())
    } else {
        Err(Error::InvalidBip34Bytes(script_prefix.to_vec()))
    }
}

/// coinbase_tx_input_script_prefix: extranonce prefix (script lenght + bip34 block height) provided
/// by the node It assume that NewTemplate.coinbase_tx_outputs == 0
fn coinbase(
    mut bip34_bytes: Vec<u8>,
    version: i32,
    lock_time: u32,
    sequence: u32,
    coinbase_outputs: &[TxOut],
    additional_coinbase_script_data_len: u8,
    extranonce_len: u8,
) -> Transaction {
    // If script_prefix_len is not 0 we are not in a test enviornment and the coinbase have the 0
    // witness
    let witness = match bip34_bytes.len() {
        0 => Witness::from_vec(vec![]),
        _ => Witness::from_vec(vec![vec![0; 32]]),
    };
    bip34_bytes.extend_from_slice(&vec![0_u8; additional_coinbase_script_data_len as usize]);
    bip34_bytes.extend_from_slice(&vec![0; extranonce_len as usize]);
    let tx_in = TxIn {
        previous_output: OutPoint::null(),
        script_sig: bip34_bytes.into(),
        sequence: bitcoin::Sequence(sequence),
        witness,
    };
    Transaction {
        version,
        lock_time: bitcoin::PackedLockTime(lock_time),
        input: vec![tx_in],
        output: coinbase_outputs.to_vec(),
    }
}

/// Helper type to strip a segwit data from the coinbase_tx_prefix and coinbase_tx_suffix
/// to ensure miners are hashing with the correct coinbase
pub fn extended_job_to_non_segwit(
    job: NewExtendedMiningJob<'static>,
    full_extranonce_len: usize,
) -> Result<NewExtendedMiningJob<'static>, Error> {
    let mut encoded = job.coinbase_tx_prefix.to_vec();
    // just add empty extranonce space so it can be deserialized. The real extranonce
    // should be inserted based on the miner's shares
    let extranonce = vec![0_u8; full_extranonce_len];
    encoded.extend_from_slice(&extranonce[..]);
    encoded.extend_from_slice(job.coinbase_tx_suffix.inner_as_ref());
    let coinbase = Transaction::deserialize(&encoded).map_err(|_| Error::InvalidCoinbase)?;
    let stripped_tx = StrippedCoinbaseTx::from_coinbase(coinbase, full_extranonce_len)?;

    Ok(NewExtendedMiningJob {
        channel_id: job.channel_id,
        job_id: job.job_id,
        min_ntime: job.min_ntime,
        version: job.version,
        version_rolling_allowed: job.version_rolling_allowed,
        merkle_path: job.merkle_path,
        coinbase_tx_prefix: stripped_tx.into_coinbase_tx_prefix()?,
        coinbase_tx_suffix: stripped_tx.into_coinbase_tx_suffix()?,
    })
}
/// Helper type to strip a segwit data from the coinbase_tx_prefix and coinbase_tx_suffix
/// to ensure miners are hashing with the correct coinbase
struct StrippedCoinbaseTx {
    version: u32,
    inputs: Vec<Vec<u8>>,
    outputs: Vec<Vec<u8>>,
    lock_time: u32,
    // helper field
    bip141_bytes_len: usize,
}

impl StrippedCoinbaseTx {
    /// create
    fn from_coinbase(tx: Transaction, full_extranonce_len: usize) -> Result<Self, Error> {
        let bip141_bytes_len = tx
            .input
            .last()
            .ok_or(Error::BadPayloadSize)?
            .script_sig
            .len()
            - full_extranonce_len;
        Ok(Self {
            version: tx.version as u32,
            inputs: tx
                .input
                .iter()
                .map(|txin| {
                    let mut ser: Vec<u8> = vec![];
                    ser.extend_from_slice(&txin.previous_output.txid);
                    ser.extend_from_slice(&txin.previous_output.vout.to_le_bytes());
                    ser.push(txin.script_sig.len() as u8);
                    ser.extend_from_slice(txin.script_sig.as_bytes());
                    ser.extend_from_slice(&txin.sequence.0.to_le_bytes());
                    ser
                })
                .collect(),
            outputs: tx.output.iter().map(|o| o.serialize()).collect(),
            lock_time: tx.lock_time.into(),
            bip141_bytes_len,
        })
    }

    /// the coinbase tx prefix is the LE bytes concatenation of the tx version and all
    /// of the tx inputs minus the extranonce bytes after the bip34 bytes in the script
    /// and the last input's sequence (used as the first entry in the coinbase tx suffix).
    /// The last bytes after the bip34 bytes in the script will be used to allow extranonce
    /// space for the miner. We remove the bip141 marker and flag since it is only used for
    /// computing the `wtxid` and the legacy `txid` is what is used for computing the merkle root
    // clippy allow because we dont want to consume self
    #[allow(clippy::wrong_self_convention)]
    fn into_coinbase_tx_prefix(&self) -> Result<B064K<'static>, errors::Error> {
        let mut inputs = self.inputs.clone();
        let last_input = inputs.last_mut().ok_or(Error::BadPayloadSize)?;
        let new_last_input_len =
        32 // outpoint
        + 4 // vout
        + 1 // script length byte -> TODO can be also 3 (based on TODO in `coinbase_tx_prefix()`)
        + self.bip141_bytes_len // space for bip34 bytes
        ;
        last_input.truncate(new_last_input_len);
        let mut prefix: Vec<u8> = vec![];
        prefix.extend_from_slice(&self.version.to_le_bytes());
        prefix.push(self.inputs.len() as u8);
        prefix.extend_from_slice(&inputs.concat());
        prefix.try_into().map_err(Error::BinarySv2Error)
    }

    /// This coinbase tx suffix is the sequence of the last tx input plus
    /// the serialized tx outputs and the lock time. Note we do not use the witnesses
    /// (placed between txouts and lock time) since it is only used for
    /// computing the `wtxid` and the legacy `txid` is what is used for computing the merkle root
    // clippy allow because we dont want to consume self
    #[allow(clippy::wrong_self_convention)]
    fn into_coinbase_tx_suffix(&self) -> Result<B064K<'static>, errors::Error> {
        let mut suffix: Vec<u8> = vec![];
        let last_input = self.inputs.last().ok_or(Error::BadPayloadSize)?;
        // only take the last intput's sequence u32 (bytes after the extranonce space)
        let last_input_sequence = &last_input[last_input.len() - 4..];
        suffix.extend_from_slice(last_input_sequence);
        suffix.push(self.outputs.len() as u8);
        suffix.extend_from_slice(&self.outputs.concat());
        suffix.extend_from_slice(&self.lock_time.to_le_bytes());
        suffix.try_into().map_err(Error::BinarySv2Error)
    }
}

// Test
#[cfg(test)]

pub mod tests {
    use super::*;
    use crate::utils::merkle_root_from_path;
    #[cfg(feature = "prop_test")]
    use binary_sv2::u256_from_int;
    use quickcheck::{Arbitrary, Gen};
    use std::{cmp, vec};

    #[cfg(feature = "prop_test")]
    use std::borrow::BorrowMut;

    use stratum_common::bitcoin::{
        consensus::Encodable, secp256k1::Secp256k1, Network, PrivateKey, PublicKey,
    };

    pub fn template_from_gen(g: &mut Gen) -> NewTemplate<'static> {
        let mut coinbase_prefix_gen = Gen::new(255);
        let mut coinbase_prefix: vec::Vec<u8> = vec::Vec::new();

        let max_num_for_script_prefix = 253;
        let prefix_len = cmp::min(u8::arbitrary(&mut coinbase_prefix_gen), 6);
        coinbase_prefix.push(prefix_len);
        coinbase_prefix.resize_with(prefix_len as usize + 2, || {
            cmp::min(
                u8::arbitrary(&mut coinbase_prefix_gen),
                max_num_for_script_prefix,
            )
        });
        let coinbase_prefix: binary_sv2::B0255 = coinbase_prefix.try_into().unwrap();

        let mut coinbase_tx_outputs_gen = Gen::new(32);
        let mut coinbase_tx_outputs_inner: vec::Vec<u8> = vec::Vec::new();
        coinbase_tx_outputs_inner.resize_with(32, || u8::arbitrary(&mut coinbase_tx_outputs_gen));
        let coinbase_tx_outputs: binary_sv2::B064K = coinbase_tx_outputs_inner.try_into().unwrap();

        let mut merkle_path_inner_gen = Gen::new(32);
        let mut merkle_path_inner: vec::Vec<u8> = vec::Vec::new();
        merkle_path_inner.resize_with(32, || u8::arbitrary(&mut merkle_path_inner_gen));
        let merkle_path_inner: binary_sv2::U256 = merkle_path_inner.try_into().unwrap();
        let merkle_path: binary_sv2::Seq0255<binary_sv2::U256> = vec![merkle_path_inner].into();

        NewTemplate {
            template_id: u64::arbitrary(g),
            future_template: bool::arbitrary(g),
            version: u32::arbitrary(g),
            coinbase_tx_version: 2,
            coinbase_prefix,
            coinbase_tx_input_sequence: u32::arbitrary(g),
            coinbase_tx_value_remaining: u64::arbitrary(g),
            coinbase_tx_outputs_count: 0,
            coinbase_tx_outputs,
            coinbase_tx_locktime: u32::arbitrary(g),
            merkle_path,
        }
    }

    const PRIVATE_KEY_BTC: [u8; 32] = [34; 32];
    const NETWORK: Network = Network::Testnet;

    #[cfg(feature = "prop_test")]
    const BLOCK_REWARD: u64 = 625_000_000_000;

    pub fn new_pub_key() -> PublicKey {
        let priv_k = PrivateKey::from_slice(&PRIVATE_KEY_BTC, NETWORK).unwrap();
        let secp = Secp256k1::default();
        let pub_k = PublicKey::from_private_key(&secp, &priv_k);
        pub_k
    }

    #[cfg(feature = "prop_test")]
    use stratum_common::bitcoin::Script;

    // Test job_id_from_template
    #[cfg(feature = "prop_test")]
    #[quickcheck_macros::quickcheck]
    fn test_job_id_from_template(mut template: NewTemplate<'static>) {
        let mut prefix = template.coinbase_prefix.to_vec();
        if prefix.len() > 0 {
            let len = u8::min(prefix[0], 6);
            prefix[0] = len;
            prefix.resize(len as usize + 2, 0);
            template.coinbase_prefix = prefix.try_into().unwrap();
        };
        let out = TxOut {
            value: BLOCK_REWARD,
            script_pubkey: Script::new_p2pk(&new_pub_key()),
        };
        let mut jobs_creators = JobsCreators::new(32);

        let job = jobs_creators
            .on_new_template(template.borrow_mut(), false, vec![out], 0)
            .unwrap();

        assert_eq!(
            jobs_creators.get_template_id_from_job(job.job_id),
            Some(template.template_id)
        );

        // Assert returns non if no match
        assert_eq!(jobs_creators.get_template_id_from_job(70), None);
    }

    // Test reset new template
    #[cfg(feature = "prop_test")]
    #[quickcheck_macros::quickcheck]
    fn test_reset_new_template(mut template: NewTemplate<'static>) {
        let out = TxOut {
            value: BLOCK_REWARD,
            script_pubkey: Script::new_p2pk(&new_pub_key()),
        };
        let mut jobs_creators = JobsCreators::new(32);

        assert_eq!(jobs_creators.lasts_new_template.len(), 0);

        let _ = jobs_creators.on_new_template(template.borrow_mut(), false, vec![out], 0);

        assert_eq!(jobs_creators.lasts_new_template.len(), 1);
        assert_eq!(jobs_creators.lasts_new_template[0], template);

        //Create a 2nd template
        let mut template2 = template_from_gen(&mut Gen::new(255));
        template2.template_id = template.template_id.checked_sub(1).unwrap_or(0);

        // Reset new template
        jobs_creators.reset_new_templates(Some(template2.clone()));

        // Should be pointing at new template
        assert_eq!(jobs_creators.lasts_new_template.len(), 1);
        assert_eq!(jobs_creators.lasts_new_template[0], template2);

        // Reset new template
        jobs_creators.reset_new_templates(None);

        // Should be pointing at new template
        assert_eq!(jobs_creators.lasts_new_template.len(), 0);
    }

    // Test on_new_prev_hash
    #[cfg(feature = "prop_test")]
    #[quickcheck_macros::quickcheck]
    fn test_on_new_prev_hash(mut template: NewTemplate<'static>) {
        let out = TxOut {
            value: BLOCK_REWARD,
            script_pubkey: Script::new_p2pk(&new_pub_key()),
        };
        let mut jobs_creators = JobsCreators::new(32);

        //Create a template
        let _ = jobs_creators.on_new_template(template.borrow_mut(), false, vec![out], 0);
        let test_id = template.template_id;

        // Create a SetNewPrevHash with matching template_id
        let prev_hash = SetNewPrevHash {
            template_id: test_id,
            prev_hash: u256_from_int(45_u32),
            header_timestamp: 0,
            n_bits: 0,
            target: ([0_u8; 32]).try_into().unwrap(),
        };

        jobs_creators.on_new_prev_hash(&prev_hash);

        //Validate that we still have the same template loaded as there were matching templateIds
        assert_eq!(jobs_creators.lasts_new_template.len(), 1);
        assert_eq!(jobs_creators.lasts_new_template[0], template);

        // Create a SetNewPrevHash with matching template_id
        let test_id_2 = test_id.wrapping_add(1);
        let prev_hash2 = SetNewPrevHash {
            template_id: test_id_2,
            prev_hash: u256_from_int(45_u32),
            header_timestamp: 0,
            n_bits: 0,
            target: ([0_u8; 32]).try_into().unwrap(),
        };

        jobs_creators.on_new_prev_hash(&prev_hash2);

        //Validate that templates were cleared as we got a new templateId in setNewPrevHash
        assert_eq!(jobs_creators.lasts_new_template.len(), 0);
    }

    #[quickcheck_macros::quickcheck]
    fn it_parse_valid_tx_outs(
        mut hash1: Vec<u8>,
        mut hash2: Vec<u8>,
        value1: u64,
        value2: u64,
        size1: u8,
        size2: u8,
    ) {
        hash1.resize(size1 as usize + 2, 0);
        hash2.resize(size2 as usize + 2, 0);
        let tx1 = TxOut {
            value: value1,
            script_pubkey: hash1.into(),
        };
        let tx2 = TxOut {
            value: value2,
            script_pubkey: hash2.into(),
        };
        let mut encoded1 = vec![];
        let mut encoded2 = vec![];
        tx1.consensus_encode(&mut encoded1).unwrap();
        tx2.consensus_encode(&mut encoded2).unwrap();
        let mut encoded = vec![];
        encoded.append(&mut encoded1.clone());
        encoded.append(&mut encoded2.clone());
        let outs = tx_outputs_to_costum_scripts(&encoded[..]);
        assert!(&outs[0] == &tx1);
        assert!(outs[1] == tx2);
    }

    // test that witness stripped tx id matches that of the txid of the coinbase
    #[test]
    fn stripped_tx_id() {
        let encoded: &[u8] = &[
            2, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 255, 255, 36, 2, 107, 22, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255,
            255, 255, 2, 0, 0, 0, 0, 0, 0, 0, 0, 67, 65, 4, 70, 109, 127, 202, 229, 99, 229, 203,
            9, 160, 209, 135, 11, 181, 128, 52, 72, 4, 97, 120, 121, 161, 73, 73, 207, 34, 40, 95,
            27, 174, 63, 39, 103, 40, 23, 108, 60, 100, 49, 248, 238, 218, 69, 56, 220, 55, 200,
            101, 226, 120, 79, 58, 158, 119, 208, 68, 243, 62, 64, 119, 151, 225, 39, 138, 172, 0,
            0, 0, 0, 0, 0, 0, 0, 38, 106, 36, 170, 33, 169, 237, 226, 246, 28, 63, 113, 209, 222,
            253, 63, 169, 153, 223, 163, 105, 83, 117, 92, 105, 6, 137, 121, 153, 98, 180, 139,
            235, 216, 54, 151, 78, 140, 249, 1, 32, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        ];
        let coinbase = Transaction::deserialize(encoded).unwrap();
        let stripped = StrippedCoinbaseTx::from_coinbase(coinbase.clone(), 32).unwrap();
        let prefix = stripped.into_coinbase_tx_prefix().unwrap().to_vec();
        let suffix = stripped.into_coinbase_tx_suffix().unwrap().to_vec();
        let extranonce = &[0_u8; 32];
        let path: &[binary_sv2::U256] = &[];
        let stripped_merkle_root =
            merkle_root_from_path(&prefix[..], &suffix[..], extranonce, path, &[]).unwrap();
        let og_merkle_root = coinbase.txid().to_vec();
        assert!(
            stripped_merkle_root == og_merkle_root,
            "stripped tx hash is not the same as bitcoin crate"
        );
    }
    #[test]
    fn stripped_tx_id_braiins_example() {
        let mut encoded = vec![];
        let coinbase_prefix = &[
            1_u8, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 255, 255, 75, 3, 176, 235, 11, 250, 190, 109, 109,
            50, 247, 22, 140, 225, 176, 1, 231, 78, 225, 50, 226, 181, 165, 55, 145, 137, 154, 46,
            9, 44, 65, 72, 231, 173, 111, 131, 26, 81, 223, 179, 225, 1, 0, 0, 0, 0, 0, 0, 0,
        ];
        let coinbase_suffix = &[
            245_u8, 192, 42, 69, 19, 47, 115, 108, 117, 115, 104, 47, 0, 0, 0, 0, 3, 78, 213, 148,
            39, 0, 0, 0, 0, 25, 118, 169, 20, 124, 21, 78, 209, 220, 89, 96, 158, 61, 38, 171, 178,
            223, 46, 163, 213, 135, 205, 140, 65, 136, 172, 0, 0, 0, 0, 0, 0, 0, 0, 44, 106, 76,
            41, 82, 83, 75, 66, 76, 79, 67, 75, 58, 214, 9, 239, 96, 221, 25, 108, 87, 155, 50, 55,
            47, 91, 115, 172, 168, 0, 12, 86, 195, 26, 241, 10, 22, 190, 151, 254, 24, 0, 78, 106,
            26, 0, 0, 0, 0, 0, 0, 0, 0, 38, 106, 36, 170, 33, 169, 237, 103, 66, 68, 105, 2, 55,
            65, 241, 216, 46, 82, 223, 150, 0, 97, 103, 2, 82, 186, 233, 145, 90, 210, 231, 35,
            100, 107, 52, 171, 233, 50, 200, 0, 0, 0, 0,
        ];
        let extranonce = vec![0_u8; 15]; // braiins pool requires 15 bytes for extranonce
        encoded.extend_from_slice(coinbase_prefix);
        let mut encoded_clone = encoded.clone();
        encoded_clone.extend_from_slice(&extranonce[..]);
        encoded_clone.extend_from_slice(coinbase_suffix);
        // let mut i = 1;
        // while let Err(_) = Transaction::deserialize(&encoded_clone) {
        //     encoded_clone = encoded.clone();
        //     extranonce.push(0);
        //     encoded_clone.extend_from_slice(&extranonce[..]);
        //     encoded_clone.extend_from_slice(coinbase_suffix);
        //     i+=1;
        // }
        // println!("SIZE: {:?}", i);
        Transaction::deserialize(&encoded_clone).unwrap();
    }
}