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

/*
 * Created on Sat Jul 24 2021
 *
 * Copyright (c) storycraft. Licensed under the MIT Licence.
 */

pub mod decode;
pub mod encode;

use std::{
    error::Error,
    fmt::Display,
    io::{self, Read, Write},
};

use futures::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt};

use crate::command::codec::decode::decode_head;

use self::encode::encode_head;

use super::{Command, HEAD_SIZE};

#[derive(Debug)]
pub enum StreamError {
    Bincode(bincode::Error),
    Io(io::Error),
}

impl From<bincode::Error> for StreamError {
    fn from(err: bincode::Error) -> Self {
        Self::Bincode(err)
    }
}

impl From<io::Error> for StreamError {
    fn from(err: io::Error) -> Self {
        Self::Io(err)
    }
}

impl Display for StreamError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            StreamError::Bincode(err) => err.fmt(f),
            StreamError::Io(err) => err.fmt(f),
        }
    }
}

impl Error for StreamError {}

/// Provide Command read / write operation to stream
#[derive(Debug)]
pub struct CommandCodec<S> {
    stream: S,
}

impl<S> CommandCodec<S> {
    pub const fn new(stream: S) -> Self {
        Self { stream }
    }

    pub const fn stream(&self) -> &S {
        &self.stream
    }

    pub fn stream_mut(&mut self) -> &mut S {
        &mut self.stream
    }

    pub fn into_inner(self) -> S {
        self.stream
    }
}

impl<S: Write> CommandCodec<S> {
    /// Write command to stream
    pub fn write(&mut self, command: &Command) -> Result<usize, StreamError> {
        let head = encode_head(&command)?;

        self.stream.write_all(&head)?;
        self.stream.write_all(&command.data)?;

        Ok(command.data.len() + HEAD_SIZE)
    }
}

impl<S: Read> CommandCodec<S> {
    /// Read one command from stream.
    /// Returns tuple with read size and Command.
    pub fn read(&mut self) -> Result<(usize, Command), StreamError> {
        let mut buf = [0u8; HEAD_SIZE];
        self.stream.read_exact(&mut buf)?;

        let mut command = decode_head(&buf)?;
        self.stream.read_exact(&mut command.data)?;

        Ok((HEAD_SIZE + command.data.len(), command))
    }
}

impl<S: AsyncRead + Unpin> CommandCodec<S> {
    /// Read one command from stream async.
    /// Returns tuple with read size and Command.
    pub async fn read_async(&mut self) -> Result<(usize, Command), StreamError> {
        let mut buf = [0u8; HEAD_SIZE];

        self.stream.read_exact(&mut buf).await?;

        let mut command = decode_head(&buf)?;
        self.stream.read_exact(&mut command.data).await?;

        Ok((HEAD_SIZE + command.data.len(), command))
    }
}

impl<S: AsyncWrite + Unpin> CommandCodec<S> {
    /// Write command to stream async
    pub async fn write_async(&mut self, command: &Command) -> Result<usize, StreamError> {
        let head = encode_head(&command)?;

        self.stream.write_all(&head).await?;
        self.stream.write_all(&command.data).await?;

        Ok(command.data.len() + HEAD_SIZE)
    }
}