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use crate::{
buffer::NetworkBuffer,
error::Result,
packet::{
deserialize_packet_header, serialize_packet, Packet, PacketBody,
PACKET_HEADER_SIZE,
},
send_bytes,
};
use mio::{
net::TcpStream,
Events, Poll, PollOpt, Ready, Token,
};
use std::{
collections::VecDeque,
io::Read,
};
const LOCAL_TOKEN: Token = Token(0);
const EVENTS_CAPACITY: usize = 4096;
pub enum ClientEvent {
Disconnected,
ReceivedPacket(usize),
SentPacket(usize),
#[doc(hidden)]
__Nonexhaustive,
}
pub struct Client {
tcp_stream: TcpStream,
events: Events,
poll: Poll,
buffer: NetworkBuffer,
incoming_packets: VecDeque<Packet>,
outgoing_packets: VecDeque<Box<dyn PacketBody>>,
is_disconnected: bool,
}
impl Client {
pub fn connect(ip: &str, port: u16) -> Result<Client> {
let address = format!("{}:{}", ip, port).parse().unwrap();
let tcp_stream = TcpStream::connect(&address)?;
let poll = Poll::new().unwrap();
poll.register(&tcp_stream, LOCAL_TOKEN, Ready::readable() | Ready::writable(), PollOpt::edge())?;
Ok(Client {
tcp_stream,
events: Events::with_capacity(EVENTS_CAPACITY),
poll,
buffer: NetworkBuffer::new(),
incoming_packets: VecDeque::new(),
outgoing_packets: VecDeque::new(),
is_disconnected: false,
})
}
pub fn is_disconnected(&self) -> bool {
self.is_disconnected
}
pub fn drain_incoming_packets(&mut self) -> Vec<Packet> {
self.incoming_packets.drain(..).collect()
}
pub fn send(&mut self, packet: impl PacketBody) {
let boxed = Box::new(packet);
self.outgoing_packets.push_back(boxed);
}
pub fn tick(&mut self) -> Vec<ClientEvent> {
if self.is_disconnected {
return Vec::new();
}
let timeout_dur = std::time::Duration::from_millis(1);
self.poll.poll(&mut self.events, Some(timeout_dur))
.unwrap_or_else(|e| panic!("Failed to poll for events! {}", e));
let mut net_events: Vec<ClientEvent> = Vec::new();
for event in self.events.iter() {
match event.token() {
LOCAL_TOKEN => {
if event.readiness().is_readable() {
loop {
match self.tcp_stream.read(&mut self.buffer.data[self.buffer.offset..]) {
Ok(0) => {
net_events.push(ClientEvent::Disconnected);
self.is_disconnected = true;
break;
},
Ok(read_bytes) => {
self.buffer.offset += read_bytes;
},
Err(e) => {
if e.kind() == std::io::ErrorKind::WouldBlock {
break;
} else {
net_events.push(ClientEvent::Disconnected);
eprintln!("Unexpected error when reading bytes! {}", e);
self.is_disconnected = true;
break;
}
}
}
}
while let Ok(header) = deserialize_packet_header(&mut self.buffer) {
let packet_size = PACKET_HEADER_SIZE + (header.size as usize);
if self.buffer.offset < packet_size {
break;
}
let bytes: &[u8] = &self.buffer.data[PACKET_HEADER_SIZE..packet_size];
let body = bytes.to_vec();
self.buffer.drain(packet_size);
let packet = Packet {
header,
body,
};
self.incoming_packets.push_back(packet);
net_events.push(ClientEvent::ReceivedPacket(packet_size));
}
}
if event.readiness().is_writable() {
while let Some(packet) = self.outgoing_packets.pop_front() {
let data = serialize_packet(packet);
match send_bytes(&mut self.tcp_stream, &data) {
Ok(sent_bytes) => {
net_events.push(ClientEvent::SentPacket(sent_bytes));
},
Err(e) => {
net_events.push(ClientEvent::Disconnected);
eprintln!("Unexpected error when sending bytes! {}", e);
self.is_disconnected = true;
break;
}
}
}
}
},
_ => unreachable!()
}
}
self.poll.reregister(&self.tcp_stream, LOCAL_TOKEN, Ready::readable() | Ready::writable(), PollOpt::edge()).unwrap();
net_events
}
}