use crate::action::{Action, ActionSignal, Props, StatefulAction, INFINITE};
use crate::comm::{QWriter, Signal, SignalId};
use crate::resource::{IoManager, ResourceManager};
use crate::server::{AsyncSignal, Config, State, SyncSignal};
use eyre::{eyre, Result};
use serde::{Deserialize, Serialize};
use std::collections::{BTreeMap, BTreeSet};
#[derive(Debug, Deserialize, Serialize)]
pub struct Merge {
in_many: BTreeSet<SignalId>,
out_one: SignalId,
}
stateful!(Merge {
in_many: BTreeSet<SignalId>,
out_one: SignalId,
});
impl Action for Merge {
#[inline]
fn in_signals(&self) -> BTreeSet<SignalId> {
self.in_many.clone()
}
#[inline]
fn out_signals(&self) -> BTreeSet<SignalId> {
BTreeSet::from([self.out_one])
}
fn init(self) -> Result<Box<dyn Action>>
where
Self: 'static + Sized,
{
if self.in_many.is_empty() {
Err(eyre!("Merge with no inputs is useless."))
} else if self.out_one == 0 {
Err(eyre!("Merge without an output is useless."))
} else if self.in_many.contains(&self.out_one) {
Err(eyre!("Merge output cannot be connected to its input."))
} else {
Ok(Box::new(self))
}
}
fn stateful(
&self,
_io: &IoManager,
_res: &ResourceManager,
_config: &Config,
_sync_writer: &QWriter<SyncSignal>,
_async_writer: &QWriter<AsyncSignal>,
) -> Result<Box<dyn StatefulAction>> {
Ok(Box::new(StatefulMerge {
done: false,
in_many: self.in_many.clone(),
out_one: self.out_one,
}))
}
}
impl StatefulAction for StatefulMerge {
impl_stateful!();
fn props(&self) -> Props {
INFINITE.into()
}
fn update(
&mut self,
signal: &ActionSignal,
_sync_writer: &mut QWriter<SyncSignal>,
_async_writer: &mut QWriter<AsyncSignal>,
state: &State,
) -> Result<Signal> {
if let ActionSignal::StateChanged(_, signal) = signal {
let mut news = BTreeMap::new();
for id in signal.iter().filter(|&i| self.in_many.contains(i)) {
if let Some(value) = state.get(id) {
news.insert(self.out_one, value.clone());
}
}
Ok(Signal::new(news))
} else {
Ok(Signal::none())
}
}
}