1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79

// Copyright (C) 2019-2023 Aleo Systems Inc.
// This file is part of the snarkVM library.

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at:
// http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use super::*;

impl<N: Network> Transactions<N> {
    /// Returns the finalize root of the transactions.
    pub fn to_finalize_root(&self, ratified_finalize_operations: Vec<FinalizeOperation<N>>) -> Result<Field<N>> {
        // Prepare the leaves.
        let leaves = self.finalize_operations().chain(&ratified_finalize_operations).map(ToBits::to_bits_le);
        // Compute the finalize tree.
        // Note: This call will check the number of finalize operations is within the size of the Merkle tree.
        let tree = N::merkle_tree_bhp::<FINALIZE_OPERATIONS_DEPTH>(&leaves.collect::<Vec<_>>())?;
        // Return the finalize root.
        Ok(*tree.root())
    }
}

impl<N: Network> Transactions<N> {
    /// Returns the transactions root, by computing the root for a Merkle tree of the transaction IDs.
    pub fn to_transactions_root(&self) -> Result<Field<N>> {
        Ok(*self.to_tree()?.root())
    }

    /// Returns the Merkle path for the transactions leaf.
    pub fn to_path(&self, transaction_id: N::TransactionID) -> Result<TransactionsPath<N>> {
        match self.transactions.get_index_of(&transaction_id) {
            Some(transaction_index) => self.to_tree()?.prove(transaction_index, &transaction_id.to_bits_le()),
            None => bail!("The transaction '{transaction_id}' is not in the block transactions"),
        }
    }

    /// The Merkle tree of transaction IDs for the block.
    pub fn to_tree(&self) -> Result<TransactionsTree<N>> {
        Self::transactions_tree(&self.transactions)
    }

    /// Returns the Merkle tree for the given transactions.
    fn transactions_tree(
        transactions: &IndexMap<N::TransactionID, ConfirmedTransaction<N>>,
    ) -> Result<TransactionsTree<N>> {
        // Ensure the number of transactions is within the allowed range.
        ensure!(
            transactions.len() <= Self::MAX_TRANSACTIONS,
            "Block cannot exceed {} transactions, found {}",
            Self::MAX_TRANSACTIONS,
            transactions.len()
        );
        // Prepare the leaves.
        let leaves = transactions.values().map(|transaction| transaction.id().to_bits_le());
        // Compute the transactions tree.
        N::merkle_tree_bhp::<TRANSACTIONS_DEPTH>(&leaves.collect::<Vec<_>>())
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use console::network::Testnet3;

    type CurrentNetwork = Testnet3;

    #[test]
    fn test_transactions_depth() {
        // Ensure the log2 relationship between depth and the maximum number of transactions.
        assert_eq!(2usize.pow(TRANSACTIONS_DEPTH as u32), Transactions::<CurrentNetwork>::MAX_TRANSACTIONS);
    }
}