nardol/packet/
packet_kind.rs

1use serde::{Deserialize, Serialize};
2
3use crate::bytes::Bytes;
4use crate::error::{Error, ErrorKind};
5use crate::ron::{FromRon, ToRon};
6
7/// Determines kind of [Packet](super::Packet).
8#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
9pub enum PacketKind {
10    /// Empty packet usually used only for testing or like a placeholder.
11    Empty,
12
13    /// Part of `metadata`.
14    MetaData,
15
16    /// Same as [MetaData](PacketKind::MetaData), only marking end of it.
17    MetaDataEnd,
18
19    /// Content packet.
20    Content,
21
22    /// Used to signalize end of the [`message`].
23    ///
24    /// Can be [TcpMessage](crate::message::TcpMessage)
25    /// or an end in general (of all times and you know it).
26    End,
27
28    /// Usually used in udp context for signaling that given [Packet](super::Packet)
29    /// is the whole `message`.
30    Unit,
31
32    /// Used in case if [PacketKind] is not recognized.
33    Unknown,
34}
35
36impl ToRon for PacketKind {}
37impl FromRon<'_> for PacketKind {}
38
39impl TryFrom<Bytes> for PacketKind {
40    type Error = Error;
41
42    fn try_from(value: Bytes) -> Result<Self, Self::Error> {
43        // Checks if value has enough bytes to parse to PacketKind (at least 2).
44        match value.get(1) {
45            Some(_) => &value[0..2],
46            None => {
47                return Err(Error::new(
48                    ErrorKind::InvalidBufferSize,
49                    Some(
50                        concat!(
51                            "impl TryFrom<Bytes> for PacketKind requires buffer of length",
52                            "of at least 2 bytes.",
53                        )
54                        .to_string(),
55                    ),
56                ))
57            }
58        };
59
60        let kind = match value[0] {
61            0 => PacketKind::Empty,
62            1 => match value[1] {
63                0 => PacketKind::MetaData,
64                1 => PacketKind::MetaDataEnd,
65                _ => PacketKind::Unknown,
66            },
67            2 => PacketKind::Content,
68            3 => PacketKind::End,
69            4 => PacketKind::Unit,
70            _ => PacketKind::Unknown,
71        };
72
73        Ok(kind)
74    }
75}
76
77impl TryFrom<&[u8]> for PacketKind {
78    type Error = Error;
79
80    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
81        // Checks if value has enough bytes to parse to PacketKind (at least 2).
82        match value.get(1) {
83            Some(_) => &value[0..2],
84            None => {
85                return Err(Error::new(
86                    ErrorKind::InvalidBufferSize,
87                    Some(
88                        concat!(
89                            "impl TryFrom<&[u8]> for PacketKind requires buffer of length",
90                            "of at least 2 bytes.",
91                        )
92                        .to_string(),
93                    ),
94                ))
95            }
96        };
97
98        let kind = match value[0] {
99            0 => PacketKind::Empty,
100            1 => match value[1] {
101                0 => PacketKind::MetaData,
102                1 => PacketKind::MetaDataEnd,
103                _ => PacketKind::Unknown,
104            },
105            2 => PacketKind::Content,
106            3 => PacketKind::End,
107            4 => PacketKind::Unit,
108            _ => PacketKind::Unknown,
109        };
110
111        Ok(kind)
112    }
113}
114
115impl From<PacketKind> for Bytes {
116    fn from(value: PacketKind) -> Self {
117        let mut bytes = Bytes::empty();
118
119        match value {
120            PacketKind::Empty => bytes.append(&mut Bytes::from([0, 0])),
121            PacketKind::MetaData => bytes.append(&mut Bytes::from([1, 0])),
122            PacketKind::MetaDataEnd => bytes.append(&mut Bytes::from([1, 1])),
123            PacketKind::Content => bytes.append(&mut Bytes::from([2, 0])),
124            PacketKind::End => bytes.append(&mut Bytes::from([3, 0])),
125            PacketKind::Unit => bytes.append(&mut Bytes::from([4, 0])),
126            PacketKind::Unknown => bytes.append(&mut Bytes::from([255, 0])),
127        }
128
129        bytes
130    }
131}
nardol/packet/packet_kind.rs

nardol/packet/
packet_kind.rs
