bdk_wallet/
types.rs

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
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
// Bitcoin Dev Kit
// Written in 2020 by Alekos Filini <alekos.filini@gmail.com>
//
// Copyright (c) 2020-2021 Bitcoin Dev Kit Developers
//
// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
// You may not use this file except in accordance with one or both of these
// licenses.

use alloc::boxed::Box;
use chain::{ChainPosition, ConfirmationBlockTime};
use core::convert::AsRef;

use bitcoin::transaction::{OutPoint, Sequence, TxOut};
use bitcoin::{psbt, Weight};

use serde::{Deserialize, Serialize};

/// Types of keychains
#[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
pub enum KeychainKind {
    /// External keychain, used for deriving recipient addresses.
    External = 0,
    /// Internal keychain, used for deriving change addresses.
    Internal = 1,
}

impl KeychainKind {
    /// Return [`KeychainKind`] as a byte
    pub fn as_byte(&self) -> u8 {
        match self {
            KeychainKind::External => b'e',
            KeychainKind::Internal => b'i',
        }
    }
}

impl AsRef<[u8]> for KeychainKind {
    fn as_ref(&self) -> &[u8] {
        match self {
            KeychainKind::External => b"e",
            KeychainKind::Internal => b"i",
        }
    }
}

/// An unspent output owned by a [`Wallet`].
///
/// [`Wallet`]: crate::Wallet
#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Hash)]
pub struct LocalOutput {
    /// Reference to a transaction output
    pub outpoint: OutPoint,
    /// Transaction output
    pub txout: TxOut,
    /// Type of keychain
    pub keychain: KeychainKind,
    /// Whether this UTXO is spent or not
    pub is_spent: bool,
    /// The derivation index for the script pubkey in the wallet
    pub derivation_index: u32,
    /// The position of the output in the blockchain.
    pub chain_position: ChainPosition<ConfirmationBlockTime>,
}

/// A [`Utxo`] with its `satisfaction_weight`.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct WeightedUtxo {
    /// The weight of the witness data and `scriptSig` expressed in [weight units]. This is used to
    /// properly maintain the feerate when adding this input to a transaction during coin selection.
    ///
    /// [weight units]: https://en.bitcoin.it/wiki/Weight_units
    pub satisfaction_weight: Weight,
    /// The UTXO
    pub utxo: Utxo,
}

#[derive(Debug, Clone, PartialEq, Eq)]
/// An unspent transaction output (UTXO).
pub enum Utxo {
    /// A UTXO owned by the local wallet.
    Local(LocalOutput),
    /// A UTXO owned by another wallet.
    Foreign {
        /// The location of the output.
        outpoint: OutPoint,
        /// The nSequence value to set for this input.
        sequence: Sequence,
        /// The information about the input we require to add it to a PSBT.
        // Box it to stop the type being too big.
        psbt_input: Box<psbt::Input>,
    },
}

impl Utxo {
    /// Get the location of the UTXO
    pub fn outpoint(&self) -> OutPoint {
        match &self {
            Utxo::Local(local) => local.outpoint,
            Utxo::Foreign { outpoint, .. } => *outpoint,
        }
    }

    /// Get the `TxOut` of the UTXO
    pub fn txout(&self) -> &TxOut {
        match &self {
            Utxo::Local(local) => &local.txout,
            Utxo::Foreign {
                outpoint,
                psbt_input,
                ..
            } => {
                if let Some(prev_tx) = &psbt_input.non_witness_utxo {
                    return &prev_tx.output[outpoint.vout as usize];
                }

                if let Some(txout) = &psbt_input.witness_utxo {
                    return txout;
                }

                unreachable!("Foreign UTXOs will always have one of these set")
            }
        }
    }

    /// Get the sequence number if an explicit sequence number has to be set for this input.
    pub fn sequence(&self) -> Option<Sequence> {
        match self {
            Utxo::Local(_) => None,
            Utxo::Foreign { sequence, .. } => Some(*sequence),
        }
    }
}