Merge pull request #1 from lithekod/rust

Initial minimum viable bot

4 files changed, 377 insertions, 0 deletions

diff --git a/src/agenda.rs b/src/agenda.rs
new file mode 100644
index 0000000..d1a940d
--- /dev/null
+++ b/src/agenda.rs
@@ -0,0 +1,91 @@
+use serde::{
+    Deserialize,
+    Serialize,
+};
+use std::{
+    fmt,
+    fs,
+};
+use tokio::sync::mpsc;
+
+#[derive(Clone, Debug, Deserialize, Serialize)]
+pub struct AgendaPoint {
+    title: String,
+    adder: String,
+}
+
+impl fmt::Display for AgendaPoint {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{} ({})", self.title, self.adder)
+    }
+}
+
+impl AgendaPoint {
+    pub fn to_add_message(&self) -> String {
+        format!("'{}' added by {}", self.title, self.adder)
+    }
+
+    fn to_add_message_response(&self) -> String {
+        //TODO should add a reaction instead
+        format!("Added '{}'", self.title)
+    }
+}
+
+#[derive(Deserialize, Serialize)]
+pub struct Agenda {
+    points: Vec<AgendaPoint>,
+}
+
+impl Agenda {
+    fn write(&self) {
+        fs::write(std::path::Path::new("agenda.json"),
+                serde_json::to_string_pretty(&self).expect("Can't serialize agenda"))
+            .expect("Can't write agenda.json");
+    }
+}
+
+pub enum ParseError {
+    NoSuchCommand,
+}
+
+pub fn parse_message(
+    message: &str,
+    sender: &str,
+    point_sender: &mpsc::UnboundedSender<AgendaPoint>
+) -> Result<Option<String>, ParseError> {
+    if message.starts_with("!add ") {
+        let mut agenda = read_agenda();
+        let agenda_point = AgendaPoint {
+            title: message[5..].to_string(),
+            adder: sender.to_string(),
+        };
+        point_sender.send(agenda_point.clone()).unwrap();
+        let response = agenda_point.to_add_message_response();
+        agenda.points.push(agenda_point);
+        agenda.write();
+        Ok(Some(response))
+    } else if message.starts_with("!agenda") {
+        Ok(Some(read_agenda()
+                .points
+                .iter()
+                .map(|p| p.to_string())
+                .collect::<Vec<_>>()
+                .join("\n")))
+    } else if message.starts_with("!clear") {
+        Agenda {
+            points: Vec::new(),
+        }.write();
+        Ok(None)
+    } else if message.starts_with("!help") {
+        Ok(Some("Available commands:\n```!add    -- Add something\n!agenda -- Print the agenda\n!clear  -- Remove all items\n!help```".to_string()))
+    } else {
+        Err(ParseError::NoSuchCommand)
+    }
+}
+
+fn read_agenda() -> Agenda {
+    serde_json::from_str::<Agenda>(
+        &fs::read_to_string("agenda.json")
+            .expect("Can't read agenda.json"))
+        .expect("Error parsing agenda.json")
+}
diff --git a/src/discord.rs b/src/discord.rs
new file mode 100644
index 0000000..0507da8
--- /dev/null
+++ b/src/discord.rs
@@ -0,0 +1,126 @@
+use crate::agenda::{
+    parse_message,
+    AgendaPoint
+};
+
+use discord::{
+    model::{
+        ChannelId,
+        Event,
+        PossibleServer,
+    },
+    Discord,
+    Error,
+};
+use futures::join;
+use std::sync::{
+    Arc,
+    Mutex,
+};
+use tokio::{
+    sync::mpsc,
+    task::{
+        spawn,
+        spawn_blocking,
+    },
+};
+
+const TOKEN: Option<&str> = None;
+const CHANNEL: Option<ChannelId> = None;
+
+pub async fn handle(
+    sender: mpsc::UnboundedSender<AgendaPoint>,
+    receiver: mpsc::UnboundedReceiver<AgendaPoint>,
+) {
+    println!("Setting up Discord");
+
+    let token = std::env::var("DISCORD_API_TOKEN").unwrap_or_else(|_| TOKEN.expect("Missing Discord token").to_string());
+    let client = Discord::from_bot_token(&token);
+
+    if let Ok(client) = client {
+        let (connection, _) = client.connect().expect("Discord connect failed"); //TODO
+        let our_id = client.get_current_user().unwrap().id;
+        let client = Arc::new(Mutex::new(client));
+
+        let channel = match std::env::var("DISCORD_CHANNEL") {
+            Ok(channel) => Some(ChannelId(channel.parse::<u64>().unwrap())),
+            Err(_) => CHANNEL,
+        };
+
+        let (_, _) = join!( //TODO?
+            spawn(receive_from_slack(receiver, Arc::clone(&client), channel)),
+            spawn_blocking(move || receive_events(our_id, connection, sender, client, channel)),
+        );
+    }
+}
+
+fn receive_events(
+    _our_id: discord::model::UserId,
+    mut connection: discord::Connection,
+    sender: mpsc::UnboundedSender<AgendaPoint>,
+    client: Arc<Mutex<discord::Discord>>,
+    channel: Option<ChannelId>,
+) {
+    loop {
+        match connection.recv_event() {
+            Ok(Event::ServerCreate(server)) => {
+                if channel.is_none() {
+                    if let PossibleServer::Online(server) = server {
+                        println!("Discord channels in {}: {:#?}",
+                                 server.name,
+                                 server
+                                 .channels
+                                 .iter()
+                                 .map(|channel| format!("{}: {} ({:?})",
+                                                        channel.name,
+                                                        channel.id,
+                                                        channel.kind))
+                                 .collect::<Vec<_>>());
+                    }
+                }
+            }
+
+            Ok(Event::MessageCreate(message)) => {
+                if let Some(channel) = channel {
+                    if channel == message.channel_id {
+                        if let Ok(Some(s)) = parse_message(
+                            &message.content,
+                            &message.author.name,
+                            &sender,
+                        ) {
+                            client.lock().unwrap().send_message(channel,
+                                                                &s,
+                                                                "",
+                                                                false).unwrap();
+                        }
+                    }
+                }
+            }
+            Ok(_) => {}
+            Err(Error::Closed(code, body)) => {
+                println!("Discord closed with code {:?}: {}", code, body);
+                break;
+            }
+            Err(e) => {
+                println!("Discord error: {:?}", e);
+            }
+        }
+    }
+}
+
+async fn receive_from_slack(
+    mut receiver: mpsc::UnboundedReceiver<AgendaPoint>,
+    client: Arc<Mutex<discord::Discord>>,
+    channel: Option<ChannelId>
+) {
+    if let Some(channel) = channel {
+        while let Some(point) = receiver.recv().await {
+            println!("Discord received '{}'", point);
+            client.lock().unwrap().send_message(channel,
+                                                &point.to_add_message(),
+                                                "",
+                                                false).unwrap();
+        }
+    }
+
+}
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..0bcf53c
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,21 @@
+mod agenda;
+mod discord;
+mod slack;
+
+use crate::agenda::AgendaPoint;
+use futures::join;
+use tokio::sync::mpsc;
+
+#[tokio::main]
+async fn main() {
+    println!("Hello, world!");
+
+    let (from_discord, to_slack) = mpsc::unbounded_channel::<AgendaPoint>();
+    let (from_slack, to_discord) = mpsc::unbounded_channel::<AgendaPoint>();
+
+    join!(
+        discord::handle(from_discord, to_discord),
+        slack::handle(from_slack, to_slack),
+    );
+}
+
diff --git a/src/slack.rs b/src/slack.rs
new file mode 100644
index 0000000..1c272cf
--- /dev/null
+++ b/src/slack.rs
@@ -0,0 +1,139 @@
+use crate::agenda::{
+    parse_message,
+    AgendaPoint
+};
+
+use futures::join;
+use slack::{
+    Event,
+    Message,
+};
+use tokio::{
+    sync::mpsc,
+    task::{
+        spawn,
+        spawn_blocking,
+    },
+};
+
+const TOKEN: Option<&str> = None;
+const CHANNEL: Option<&str> = None;
+
+struct Handler {
+    sender: mpsc::UnboundedSender<AgendaPoint>,
+    slack_sender: slack::Sender,
+    slack_channel: Option<String>,
+    print_channels: bool,
+}
+
+impl Handler {
+    fn new(
+        sender: mpsc::UnboundedSender<AgendaPoint>,
+        slack_sender: slack::Sender,
+        slack_channel: Option<String>,
+    ) -> Self {
+        Self {
+            sender,
+            slack_sender,
+            slack_channel: slack_channel.clone(),
+            print_channels: slack_channel.is_none()
+        }
+    }
+}
+
+impl slack::EventHandler for Handler {
+    fn on_event(&mut self, cli: &slack::RtmClient, event: slack::Event) {
+        match event {
+            Event::Hello => {
+                if self.print_channels {
+                    println!("Slack channels found: {:#?}",
+                             cli
+                             .start_response()
+                             .channels
+                             .as_ref()
+                             .and_then(|channels| {
+                                 Some(channels
+                                      .iter()
+                                      .map(|channel| format!("{}: {}",
+                                                             channel.name.as_ref().unwrap_or(&"??".to_string()), //TODO &"".to_string() ?
+                                                             channel.id.as_ref().unwrap_or(&"??".to_string())))  //TODO
+                                      .collect::<Vec<_>>())
+                             }));
+                }
+            }
+            Event::Message(msg) => {
+                if let Some(channel) = &self.slack_channel {
+                    match *msg {
+                        Message::Standard(msg) => {
+                            if msg.channel.is_some() && *channel == msg.channel.unwrap() { //TODO
+                                if let Ok(Some(s)) = parse_message(
+                                    &msg.text.unwrap_or("".to_string()),
+                                    &msg.user.unwrap_or("??".to_string()),
+                                    &self.sender,
+                                ) {
+                                    self.slack_sender.send_message(channel.as_str(), &s).unwrap();
+                                }
+                            }
+                        }
+                        _ => {} // message type
+                    }
+                }
+            }
+            _ => {} // event type
+        }
+    }
+
+    fn on_close(&mut self, _cli: &slack::RtmClient) {}
+
+    fn on_connect(&mut self, _cli: &slack::RtmClient) {}
+}
+
+pub async fn handle(
+    sender: mpsc::UnboundedSender<AgendaPoint>,
+    receiver: mpsc::UnboundedReceiver<AgendaPoint>,
+) {
+    println!("Setting up Slack");
+
+    let token = std::env::var("SLACK_API_TOKEN").unwrap_or_else(|_| TOKEN.expect("Missing slack token").to_string());
+    let channel = match std::env::var("SLACK_CHANNEL") {
+        Ok(channel) => Some(channel),
+        Err(_) => match CHANNEL {
+            Some(channel) => Some(channel.to_string()),
+            None => None
+        }
+    };
+    let client = spawn_blocking(move || {
+        slack::RtmClient::login(&token).unwrap()
+    }).await.unwrap();
+
+    let mut handler = Handler::new(sender, client.sender().clone(), channel.clone());
+    let slack_sender = client.sender().clone();
+
+    let (_, _) = join!(
+        spawn_blocking(move || {
+            match client.run(&mut handler) {
+                Ok(_) => {}
+                Err(e) => {
+                    println!("Error: {}", e)
+                }
+            }
+        }),
+        spawn(receive_from_discord(receiver, slack_sender, channel))
+    );
+}
+
+async fn receive_from_discord(
+    mut receiver: mpsc::UnboundedReceiver<AgendaPoint>,
+    sender: slack::Sender,
+    channel: Option<String>,
+) {
+    if let Some(channel) = channel {
+        while let Some(point) = receiver.recv().await {
+            //TODO Sending messages is very slow sometimes. Have seen delays
+            // from 5 up to 20(!) seconds.
+            sender.send_typing(&channel).unwrap();
+            sender.send_message(&channel, &point.to_add_message()).unwrap();
+            println!("Slack message sent");
+        }
+    }
+}