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
136
137
138
139
140
141

use crate::{
    error::{Error, Result},
    sequence_message::SequenceMessage,
};
use bitcoin::{
    consensus::{deserialize, serialize},
    hashes::Hash,
    Block, BlockHash, Transaction, Txid,
};
use core::fmt;

#[derive(Debug, PartialEq, Eq, Clone)]
pub enum Message {
    HashBlock(BlockHash, u32),
    HashTx(Txid, u32),
    Block(Block, u32),
    Tx(Transaction, u32),
    Sequence(SequenceMessage, u32),
}

impl Message {
    /// Returns the topic of this [`Message`] as a byte slice.
    #[inline]
    pub fn topic(&self) -> &'static [u8] {
        self.topic_str().as_bytes()
    }

    /// Returns the topic of this [`Message`] as a string slice.
    #[inline]
    pub fn topic_str(&self) -> &'static str {
        match self {
            Self::HashBlock(..) => "hashblock",
            Self::HashTx(..) => "hashtx",
            Self::Block(..) => "block",
            Self::Tx(..) => "tx",
            Self::Sequence(..) => "sequence",
        }
    }

    /// Serializes the middle part of this [`Message`] (no topic and sequence).
    #[inline]
    pub fn content(&self) -> Vec<u8> {
        let mut arr = match self {
            Self::HashBlock(blockhash, _) => blockhash.to_byte_array(),
            Self::HashTx(txid, _) => txid.to_byte_array(),
            Self::Block(block, _) => return serialize(&block),
            Self::Tx(tx, _) => return serialize(&tx),
            Self::Sequence(sm, _) => return (*sm).into(),
        };
        arr.reverse();
        arr.to_vec()
    }

    /// Returns the sequence of this [`Message`], a number that starts at 0 and goes up every time
    /// Bitcoin Core sends a ZMQ message per publisher
    #[inline]
    pub fn sequence(&self) -> u32 {
        match self {
            Self::HashBlock(_, seq)
            | Self::HashTx(_, seq)
            | Self::Block(_, seq)
            | Self::Tx(_, seq)
            | Self::Sequence(_, seq) => *seq,
        }
    }
}

impl TryFrom<[Vec<u8>; 3]> for Message {
    type Error = Error;

    fn try_from(value: [Vec<u8>; 3]) -> Result<Self> {
        let [topic, content, seq] = value;

        if seq.len() != 4 {
            return Err(Error::InvalidSequenceLengthError(seq.len()));
        }
        let seq = u32::from_le_bytes(seq.try_into().unwrap());

        Ok(match &topic[..] {
            b"hashblock" | b"hashtx" => {
                if content.len() != 32 {
                    return Err(Error::Invalid256BitHashLengthError(content.len()));
                }
                let mut content: [u8; 32] = content.try_into().unwrap();
                content.reverse();

                match &topic[..] {
                    b"hashblock" => Self::HashBlock(BlockHash::from_byte_array(content), seq),
                    _ /* b"hashtx" */ => Self::HashTx(Txid::from_byte_array(content), seq),
                }
            }
            b"rawblock" => Self::Block(deserialize(&content)?, seq),
            b"rawtx" => Self::Tx(deserialize(&content)?, seq),
            b"sequence" => Self::Sequence(content.try_into()?, seq),
            _ => return Err(Error::InvalidTopicError(topic)),
        })
    }
}

impl TryFrom<Vec<Vec<u8>>> for Message {
    type Error = Error;

    #[inline]
    fn try_from(value: Vec<Vec<u8>>) -> Result<Self> {
        if value.len() != 3 {
            return Err(Error::InvalidMutlipartLengthError(value.len()));
        }
        let arr: [Vec<u8>; 3] = value.try_into().unwrap();
        arr.try_into()
    }
}

impl From<Message> for [Vec<u8>; 3] {
    fn from(msg: Message) -> Self {
        [
            msg.topic().to_vec(),
            msg.content(),
            msg.sequence().to_le_bytes().to_vec(),
        ]
    }
}

impl From<Message> for Vec<Vec<u8>> {
    #[inline]
    fn from(msg: Message) -> Self {
        let arr: [Vec<u8>; 3] = msg.into();
        arr.to_vec()
    }
}

impl fmt::Display for Message {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::HashBlock(blockhash, seq) => write!(f, "HashBlock({blockhash}, sequence={seq})"),
            Self::HashTx(txid, seq) => write!(f, "HashTx({txid}, sequence={seq})"),
            Self::Block(block, seq) => write!(f, "Block({}, sequence={seq})", block.block_hash()),
            Self::Tx(tx, seq) => write!(f, "Tx({}, sequence={seq})", tx.txid()),
            Self::Sequence(sm, seq) => write!(f, "Sequence({sm}, sequence={seq})"),
        }
    }
}