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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185

use anyhow::{anyhow, Result};
use async_cell::sync::AsyncCell;
use dashmap::DashMap;
use lunatic_process::runtimes::RawWasm;
use std::{
    net::SocketAddr,
    sync::{atomic, atomic::AtomicU64, Arc, RwLock},
    time::Duration,
};

use crate::{
    control::message::{Registered, Registration, Request, Response},
    quic::{self, Connection},
    NodeInfo,
};

use super::server::CTRL_SERVER_NAME;

#[derive(Clone)]
pub struct Client {
    inner: Arc<InnerClient>,
}

pub struct InnerClient {
    next_message_id: AtomicU64,
    node_addr: SocketAddr,
    node_name: String,
    control_addr: SocketAddr,
    connection: Connection,
    pending_requests: DashMap<u64, Arc<AsyncCell<Response>>>,
    nodes: DashMap<u64, NodeInfo>,
    node_ids: RwLock<Vec<u64>>,
}

impl Client {
    pub async fn register(
        node_addr: SocketAddr,
        node_name: String,
        control_addr: SocketAddr,
        quic_client: quic::Client,
        signing_request: String,
    ) -> Result<(u64, Self, String)> {
        let client = Client {
            inner: Arc::new(InnerClient {
                next_message_id: AtomicU64::new(1),
                control_addr,
                node_addr,
                node_name,
                connection: quic_client
                    .connect(control_addr, CTRL_SERVER_NAME, 5)
                    .await?,
                pending_requests: DashMap::new(),
                nodes: Default::default(),
                node_ids: Default::default(),
            }),
        };
        // Spawn reader task before register
        tokio::task::spawn(reader_task(client.clone()));
        tokio::task::spawn(refresh_nodes_task(client.clone()));
        let Registered {
            node_id,
            signed_cert,
        } = client.send_registration(signing_request).await?;

        Ok((node_id, client, signed_cert))
    }

    pub fn next_message_id(&self) -> u64 {
        self.inner
            .next_message_id
            .fetch_add(1, atomic::Ordering::Relaxed)
    }

    pub fn connection(&self) -> &Connection {
        &self.inner.connection
    }

    pub fn control_addr(&self) -> SocketAddr {
        self.inner.control_addr
    }

    pub async fn send(&self, req: Request) -> Result<Response> {
        let msg_id = self.next_message_id();
        self.inner.connection.send(msg_id, req).await?;
        let cell = AsyncCell::shared();
        self.inner.pending_requests.insert(msg_id, cell.clone());
        let response = cell.take().await;
        self.inner.pending_requests.remove(&msg_id);
        Ok(response)
    }

    pub async fn recv(&self) -> Result<(u64, Response)> {
        self.inner.connection.receive().await
    }

    async fn send_registration(&self, signing_request: String) -> Result<Registered> {
        let reg = Registration {
            node_address: self.inner.node_addr,
            node_name: self.inner.node_name.clone(),
            signing_request,
        };
        let resp = self.send(Request::Register(reg)).await?;
        match resp {
            Response::Register(data) => Ok(data),
            Response::Error(e) => Err(anyhow!("Registration failed. {e}")),
            _ => Err(anyhow!("Registration failed.")),
        }
    }

    fn process_response(&self, id: u64, resp: Response) {
        if let Some(e) = self.inner.pending_requests.get(&id) {
            e.set(resp);
        };
    }

    pub async fn refresh_nodes(&self) -> Result<()> {
        if let Response::Nodes(nodes) = self.send(Request::ListNodes).await? {
            let mut node_ids = vec![];
            for (id, reg) in nodes {
                node_ids.push(id);
                if !self.inner.nodes.contains_key(&id) {
                    self.inner.nodes.insert(
                        id,
                        NodeInfo {
                            id,
                            address: reg.node_address,
                            name: reg.node_name,
                        },
                    );
                }
            }
            if let Ok(mut self_node_ids) = self.inner.node_ids.write() {
                *self_node_ids = node_ids;
            }
        }
        Ok(())
    }

    pub async fn deregister(&self, node_id: u64) {
        self.send(Request::Deregister(node_id)).await.ok();
    }

    pub fn node_info(&self, node_id: u64) -> Option<NodeInfo> {
        self.inner.nodes.get(&node_id).map(|e| e.clone())
    }

    pub fn node_ids(&self) -> Vec<u64> {
        self.inner.node_ids.read().unwrap().clone()
    }

    pub fn node_count(&self) -> usize {
        self.inner.node_ids.read().unwrap().len()
    }

    pub async fn get_module(&self, module_id: u64) -> Option<Vec<u8>> {
        if let Ok(Response::Module(module)) = self.send(Request::GetModule(module_id)).await {
            module
        } else {
            None
        }
    }

    pub async fn add_module(&self, module: Vec<u8>) -> Result<RawWasm> {
        if let Response::ModuleId(id) = self.send(Request::AddModule(module.clone())).await? {
            Ok(RawWasm::new(Some(id), module))
        } else {
            Err(anyhow::anyhow!("Invalid response type on add_module."))
        }
    }
}

async fn reader_task(client: Client) -> Result<()> {
    loop {
        if let Ok((id, resp)) = client.recv().await {
            client.process_response(id, resp);
        }
    }
}

async fn refresh_nodes_task(client: Client) -> Result<()> {
    loop {
        client.refresh_nodes().await.ok();
        tokio::time::sleep(Duration::from_secs(5)).await;
    }
}