4 files changed, 473 insertions, 0 deletions
diff --git a/planetwars-localdev/src/match_runner/bot_runner.rs b/planetwars-localdev/src/match_runner/bot_runner.rs
new file mode 100644
index 0000000..290df07
--- /dev/null
+++ b/planetwars-localdev/src/match_runner/bot_runner.rs
@@ -0,0 +1,120 @@
+use std::io;
+use std::process::Stdio;
+use std::sync::Arc;
+use std::sync::Mutex;
+use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader, Lines};
+use tokio::process;
+use tokio::sync::mpsc;
+use tokio::time::timeout;
+
+use super::match_context::EventBus;
+use super::match_context::PlayerHandle;
+use super::match_context::RequestError;
+use super::match_context::RequestMessage;
+pub struct LocalBotHandle {
+    tx: mpsc::UnboundedSender<RequestMessage>,
+}
+
+impl PlayerHandle for LocalBotHandle {
+    fn send_request(&mut self, r: RequestMessage) {
+        self.tx
+            .send(r)
+            .expect("failed to send message to local bot");
+    }
+
+    fn send_info(&mut self, _msg: String) {
+        // TODO: log this somewhere
+        // drop info message
+    }
+}
+
+pub fn run_local_bot(player_id: u32, event_bus: Arc<Mutex<EventBus>>, bot: Bot) -> LocalBotHandle {
+    let (tx, rx) = mpsc::unbounded_channel();
+
+    let runner = LocalBotRunner {
+        event_bus,
+        rx,
+        player_id,
+        bot,
+    };
+    tokio::spawn(runner.run());
+
+    return LocalBotHandle { tx };
+}
+
+pub struct LocalBotRunner {
+    event_bus: Arc<Mutex<EventBus>>,
+    rx: mpsc::UnboundedReceiver<RequestMessage>,
+    player_id: u32,
+    bot: Bot,
+}
+
+impl LocalBotRunner {
+    pub async fn run(mut self) {
+        let mut process = self.bot.spawn_process();
+
+        while let Some(request) = self.rx.recv().await {
+            let resp_fut = process.communicate(&request.content);
+            let result = timeout(request.timeout, resp_fut)
+                .await
+                // TODO: how can this failure be handled cleanly?
+                .expect("process read failed");
+            let result = match result {
+                Ok(line) => Ok(line.into_bytes()),
+                Err(_elapsed) => Err(RequestError::Timeout),
+            };
+            let request_id = (self.player_id, request.request_id);
+
+            self.event_bus
+                .lock()
+                .unwrap()
+                .resolve_request(request_id, result);
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct Bot {
+    pub working_dir: String,
+    pub argv: Vec<String>,
+}
+
+impl Bot {
+    pub fn spawn_process(&self) -> BotProcess {
+        let mut child = process::Command::new(&self.argv[0])
+            .args(&self.argv[1..])
+            .current_dir(self.working_dir.clone())
+            .kill_on_drop(true)
+            .stdin(Stdio::piped())
+            .stdout(Stdio::piped())
+            .stderr(Stdio::inherit())
+            .spawn()
+            .expect("spawning failed");
+
+        let stdout = child.stdout.take().unwrap();
+        let reader = BufReader::new(stdout).lines();
+
+        return BotProcess {
+            stdin: child.stdin.take().unwrap(),
+            stdout: reader,
+            child,
+        };
+    }
+}
+
+pub struct BotProcess {
+    #[allow(dead_code)]
+    child: process::Child,
+    stdin: process::ChildStdin,
+    stdout: Lines<BufReader<process::ChildStdout>>,
+}
+
+impl BotProcess {
+    // TODO: gracefully handle errors
+    pub async fn communicate(&mut self, input: &[u8]) -> io::Result<String> {
+        self.stdin.write_all(input).await?;
+        self.stdin.write_u8(b'\n').await?;
+        let line = self.stdout.next_line().await?;
+        line.ok_or_else(|| io::Error::new(io::ErrorKind::UnexpectedEof, "no response received"))
+    }
+}
diff --git a/planetwars-localdev/src/match_runner/match_context.rs b/planetwars-localdev/src/match_runner/match_context.rs
new file mode 100644
index 0000000..466da13
--- /dev/null
+++ b/planetwars-localdev/src/match_runner/match_context.rs
@@ -0,0 +1,161 @@
+use futures::task::{Context, Poll};
+use futures::{future::Future, task::AtomicWaker};
+use serde::{Deserialize, Serialize};
+use std::fs::File;
+use std::io::Write;
+use std::pin::Pin;
+use std::time::Duration;
+use std::{
+    collections::HashMap,
+    sync::{Arc, Mutex},
+};
+
+#[derive(Serialize, Deserialize, Debug)]
+pub struct RequestMessage {
+    pub request_id: u32,
+    pub timeout: Duration,
+    pub content: Vec<u8>,
+}
+
+pub struct MatchCtx {
+    event_bus: Arc<Mutex<EventBus>>,
+    players: HashMap<u32, PlayerData>,
+    // output: MsgStreamHandle<String>,
+    log_sink: File,
+}
+
+impl MatchCtx {
+    pub fn new(
+        event_bus: Arc<Mutex<EventBus>>,
+        players: HashMap<u32, Box<dyn PlayerHandle>>,
+        log_file: File,
+        // log: MsgStreamHandle<String>,
+    ) -> Self {
+        MatchCtx {
+            event_bus,
+            players: players
+                .into_iter()
+                .map(|(id, handle)| {
+                    let player_handle = PlayerData {
+                        request_ctr: 0,
+                        handle,
+                    };
+                    (id, player_handle)
+                })
+                .collect(),
+            log_sink: log_file,
+        }
+    }
+
+    // TODO: implement a clean way to handle the player not existing
+    pub fn request(&mut self, player_id: u32, content: Vec<u8>, timeout: Duration) -> Request {
+        let player = self.players.get_mut(&player_id).unwrap();
+        let request_id = player.request_ctr;
+        player.request_ctr += 1;
+
+        player.handle.send_request(RequestMessage {
+            request_id,
+            content,
+            timeout,
+        });
+
+        return Request {
+            player_id,
+            request_id,
+            event_bus: self.event_bus.clone(),
+        };
+    }
+
+    pub fn send_info(&mut self, player_id: u32, msg: String) {
+        let player = self.players.get_mut(&player_id).unwrap();
+        player.handle.send_info(msg);
+    }
+
+    pub fn players(&self) -> Vec<u32> {
+        self.players.keys().cloned().collect()
+    }
+
+    // this method should be used to emit log states etc.
+    pub fn log_string(&mut self, message: String) {
+        write!(self.log_sink, "{}\n", message).expect("failed to write to log file");
+    }
+}
+
+pub trait PlayerHandle: Send {
+    fn send_request(&mut self, r: RequestMessage);
+    fn send_info(&mut self, msg: String);
+}
+
+struct PlayerData {
+    request_ctr: u32,
+    handle: Box<dyn PlayerHandle>,
+}
+
+type RequestId = (u32, u32);
+pub struct EventBus {
+    request_responses: HashMap<RequestId, RequestResult<Vec<u8>>>,
+    wakers: HashMap<RequestId, AtomicWaker>,
+}
+
+impl EventBus {
+    pub fn new() -> Self {
+        EventBus {
+            request_responses: HashMap::new(),
+            wakers: HashMap::new(),
+        }
+    }
+}
+
+impl EventBus {
+    pub fn resolve_request(&mut self, id: RequestId, result: RequestResult<Vec<u8>>) {
+        if self.request_responses.contains_key(&id) {
+            // request already resolved
+            // TODO: maybe report this?
+            return;
+        }
+        self.request_responses.insert(id, result);
+        if let Some(waker) = self.wakers.remove(&id) {
+            waker.wake();
+        }
+    }
+}
+
+pub struct Request {
+    player_id: u32,
+    request_id: u32,
+    event_bus: Arc<Mutex<EventBus>>,
+}
+
+impl Request {
+    #[allow(dead_code)]
+    pub fn player_id(&self) -> u32 {
+        self.player_id
+    }
+}
+
+impl Future for Request {
+    type Output = RequestResult<Vec<u8>>;
+
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let mut event_bus = self.event_bus.lock().unwrap();
+        let request_id = (self.player_id, self.request_id);
+
+        if let Some(result) = event_bus.request_responses.get(&request_id) {
+            return Poll::Ready(result.clone());
+        }
+
+        event_bus
+            .wakers
+            .entry(request_id)
+            .or_insert_with(|| AtomicWaker::new())
+            .register(cx.waker());
+        return Poll::Pending;
+    }
+}
+
+#[derive(Debug, Clone)]
+pub enum RequestError {
+    Timeout,
+}
+
+pub type RequestResult<T> = Result<T, RequestError>;
diff --git a/planetwars-localdev/src/match_runner/mod.rs b/planetwars-localdev/src/match_runner/mod.rs
new file mode 100644
index 0000000..2715b96
--- /dev/null
+++ b/planetwars-localdev/src/match_runner/mod.rs
@@ -0,0 +1,56 @@
+mod bot_runner;
+mod match_context;
+mod pw_match;
+
+use std::{
+    path::PathBuf,
+    sync::{Arc, Mutex},
+};
+
+use match_context::MatchCtx;
+use planetwars_rules::PwConfig;
+
+use crate::BotConfig;
+
+use self::match_context::{EventBus, PlayerHandle};
+
+pub struct MatchConfig {
+    pub map_path: PathBuf,
+    pub log_path: PathBuf,
+    pub players: Vec<MatchBot>,
+}
+
+pub struct MatchBot {
+    pub name: String,
+    pub bot_config: BotConfig,
+}
+
+pub async fn run_match(config: MatchConfig) {
+    let pw_config = PwConfig {
+        map_file: config.map_path,
+        max_turns: 100,
+    };
+
+    let event_bus = Arc::new(Mutex::new(EventBus::new()));
+
+    // start bots
+    let players = config
+        .players
+        .iter()
+        .enumerate()
+        .map(|(player_id, bot)| {
+            let player_id = (player_id + 1) as u32;
+            let bot = bot_runner::Bot {
+                working_dir: bot.bot_config.path.clone(),
+                argv: bot.bot_config.argv.clone(),
+            };
+            let handle = bot_runner::run_local_bot(player_id, event_bus.clone(), bot);
+            (player_id, Box::new(handle) as Box<dyn PlayerHandle>)
+        })
+        .collect();
+    let log_file = std::fs::File::create(config.log_path).expect("could not create log file");
+    let match_ctx = MatchCtx::new(event_bus, players, log_file);
+
+    let match_state = pw_match::PwMatch::create(match_ctx, pw_config);
+    match_state.run().await;
+}
diff --git a/planetwars-localdev/src/match_runner/pw_match.rs b/planetwars-localdev/src/match_runner/pw_match.rs
new file mode 100644
index 0000000..42bc9d2
--- /dev/null
+++ b/planetwars-localdev/src/match_runner/pw_match.rs
@@ -0,0 +1,136 @@
+use super::match_context::{MatchCtx, RequestResult};
+use futures::stream::futures_unordered::FuturesUnordered;
+use futures::{FutureExt, StreamExt};
+use serde::{Deserialize, Serialize};
+use tokio::time::Duration;
+
+use serde_json;
+
+use std::convert::TryInto;
+
+pub use planetwars_rules::config::{Config, Map};
+
+use planetwars_rules::protocol::{self as proto, PlayerAction};
+use planetwars_rules::serializer as pw_serializer;
+use planetwars_rules::{PlanetWars, PwConfig};
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct MatchConfig {
+    pub map_name: String,
+    pub max_turns: usize,
+}
+
+pub struct PwMatch {
+    match_ctx: MatchCtx,
+    match_state: PlanetWars,
+}
+
+impl PwMatch {
+    pub fn create(match_ctx: MatchCtx, config: PwConfig) -> Self {
+        // TODO: this is kind of hacked together at the moment
+        let match_state = PlanetWars::create(config, match_ctx.players().len());
+
+        PwMatch {
+            match_state,
+            match_ctx,
+        }
+    }
+
+    pub async fn run(mut self) {
+        while !self.match_state.is_finished() {
+            let player_messages = self.prompt_players().await;
+
+            for (player_id, turn) in player_messages {
+                let res = self.execute_action(player_id, turn);
+                if let Some(err) = action_errors(res) {
+                    let info_str = serde_json::to_string(&err).unwrap();
+                    self.match_ctx.send_info(player_id as u32, info_str);
+                }
+            }
+            self.match_state.step();
+
+            // Log state
+            let state = self.match_state.serialize_state();
+            self.match_ctx
+                .log_string(serde_json::to_string(&state).unwrap());
+        }
+    }
+
+    async fn prompt_players(&mut self) -> Vec<(usize, RequestResult<Vec<u8>>)> {
+        // borrow these outside closure to make the borrow checker happy
+        let state = self.match_state.state();
+        let match_ctx = &mut self.match_ctx;
+
+        // TODO: this numbering is really messy.
+        // Get rid of the distinction between player_num
+        // and player_id.
+
+        self.match_state
+            .state()
+            .players
+            .iter()
+            .filter(|p| p.alive)
+            .map(move |player| {
+                let state_for_player = pw_serializer::serialize_rotated(&state, player.id - 1);
+                match_ctx
+                    .request(
+                        player.id.try_into().unwrap(),
+                        serde_json::to_vec(&state_for_player).unwrap(),
+                        Duration::from_millis(1000),
+                    )
+                    .map(move |resp| (player.id, resp))
+            })
+            .collect::<FuturesUnordered<_>>()
+            .collect::<Vec<_>>()
+            .await
+    }
+
+    fn execute_action(
+        &mut self,
+        player_num: usize,
+        turn: RequestResult<Vec<u8>>,
+    ) -> proto::PlayerAction {
+        let turn = match turn {
+            Err(_timeout) => return proto::PlayerAction::Timeout,
+            Ok(data) => data,
+        };
+
+        let action: proto::Action = match serde_json::from_slice(&turn) {
+            Err(err) => return proto::PlayerAction::ParseError(err.to_string()),
+            Ok(action) => action,
+        };
+
+        let commands = action
+            .commands
+            .into_iter()
+            .map(|command| {
+                let res = self.match_state.execute_command(player_num, &command);
+                proto::PlayerCommand {
+                    command,
+                    error: res.err(),
+                }
+            })
+            .collect();
+
+        return proto::PlayerAction::Commands(commands);
+    }
+}
+
+fn action_errors(action: PlayerAction) -> Option<PlayerAction> {
+    match action {
+        PlayerAction::Commands(commands) => {
+            let failed = commands
+                .into_iter()
+                .filter(|cmd| cmd.error.is_some())
+                .collect::<Vec<_>>();
+
+            if failed.is_empty() {
+                None
+            } else {
+                Some(PlayerAction::Commands(failed))
+            }
+        }
+        e => Some(e),
+    }
+}