feat(core): early structure of the engine

Cargo.lock

@@ -287,6 +287,7 @@ version = "1.0.0"
 dependencies = [
  "anyhow",
  "clap",
+ "crossbeam",
  "espanso-clipboard",
  "espanso-config",
  "espanso-detect",

espanso/Cargo.toml

@@ -29,3 +29,4 @@ anyhow = "1.0.38"
 thiserror = "1.0.23"
 clap = "2.33.3"
 lazy_static = "1.4.0"
+crossbeam = "0.8.0"

espanso/src/cli/mod.rs

@@ -23,6 +23,7 @@ use espanso_path::Paths;
 
 pub mod log;
 pub mod path;
+pub mod worker;
 
 pub struct CliModule {
   pub enable_logs: bool,

espanso/src/cli/worker/mod.rs

@@ -0,0 +1,44 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use crate::engine::{Engine, funnel};
+use super::{CliModule, CliModuleArgs};
+
+mod source;
+
+pub fn new() -> CliModule {
+  #[allow(clippy::needless_update)]
+  CliModule {
+    requires_paths: true,
+    requires_config: true,
+    enable_logs: true,
+    subcommand: "worker".to_string(),
+    entry: worker_main,
+    ..Default::default()
+  }
+}
+
+fn worker_main(args: CliModuleArgs) {
+  let funnel = funnel::default(vec![
+    Box::new(),
+  ]);
+
+  let engine = Engine::new(funnel);
+}
+

espanso/src/cli/worker/source/detect.rs

@@ -0,0 +1,41 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use crossbeam::channel::{Receiver, Select, SelectedOperation};
+use espanso_detect::event::InputEvent;
+
+use crate::engine::{event::Event, funnel::Source};
+
+pub struct DetectorSource {
+  receiver: Receiver<InputEvent>,
+}
+
+impl Source for DetectorSource {
+  fn register(&self, select: &Select) -> i32 {
+    todo!()
+  }
+
+  fn receive(&self, select: &SelectedOperation) -> Event {
+    todo!()
+  }
+}
+
+pub fn new() {
+  todo!()
+}

espanso/src/cli/worker/source/mod.rs

@@ -0,0 +1,20 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+pub mod detect;

espanso/src/engine/dispatch/default.rs

@@ -0,0 +1,45 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use super::{Dispatcher, Executor, TextInjector};
+use super::Event;
+
+pub struct DefaultDispatcher {
+  executors: Vec<Box<dyn Executor>>,
+}
+
+impl DefaultDispatcher {
+  pub fn new(text_injector: impl TextInjector + 'static) -> Self {
+    Self {
+      executors: vec![
+        Box::new(super::executor::text_inject::TextInjectExecutor::new(text_injector)),
+      ]
+    }
+  }
+}
+
+impl Dispatcher for DefaultDispatcher {
+  fn dispatch(&self, event: Event) {
+    for executor in self.executors.iter() {
+      if executor.execute(&event) {
+        break
+      }
+    }
+  }
+}

espanso/src/engine/dispatch/executor/mod.rs

@@ -0,0 +1,20 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+pub mod text_inject;

espanso/src/engine/dispatch/executor/text_inject.rs

@@ -0,0 +1,47 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use super::super::{Event, Executor, TextInjector};
+use crate::engine::event::inject::TextInjectMode;
+use log::error;
+
+pub struct TextInjectExecutor<T: TextInjector> {
+  injector: T,
+}
+
+impl<T: TextInjector> TextInjectExecutor<T> {
+  pub fn new(injector: T) -> Self {
+    Self { injector }
+  }
+}
+
+impl<T: TextInjector> Executor for TextInjectExecutor<T> {
+  fn execute(&self, event: &Event) -> bool {
+    if let Event::TextInject(inject_event) = event {
+      if inject_event.mode == TextInjectMode::Keys {
+        if let Err(error) = self.injector.inject(&inject_event.text) {
+          error!("text injector reported an error: {:?}", error);
+        }
+        return true;
+      }
+    }
+
+    false
+  }
+}

espanso/src/engine/dispatch/mod.rs

@@ -0,0 +1,42 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use anyhow::Result;
+use super::Event;
+
+mod executor;
+mod default;
+
+pub trait Executor {
+  fn execute(&self, event: &Event) -> bool;
+}
+
+pub trait Dispatcher {
+  fn dispatch(&self, event: Event);
+}
+
+pub trait TextInjector {
+  fn inject(&self, text: &str) -> Result<()>;
+}
+
+pub fn default(text_injector: impl TextInjector + 'static) -> impl Dispatcher {
+  default::DefaultDispatcher::new(
+    text_injector,
+  )
+}

espanso/src/engine/event/inject.rs

@@ -0,0 +1,30 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#[derive(Debug)]
+pub struct TextInjectEvent {
+  pub text: String,
+  pub mode: TextInjectMode,
+}
+
+#[derive(Debug, PartialEq)]
+pub enum TextInjectMode {
+  Keys,
+  Clipboard,
+}

espanso/src/engine/event/keyboard.rs

@@ -0,0 +1,95 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#[derive(Debug, PartialEq)]
+pub enum Status {
+  Pressed,
+  Released,
+}
+
+#[derive(Debug, PartialEq)]
+pub enum Variant {
+  Left,
+  Right,
+}
+
+#[derive(Debug, PartialEq)]
+pub struct KeyboardEvent {
+  pub key: Key,
+  pub value: Option<String>,
+  pub status: Status,
+  pub variant: Option<Variant>,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum Key {
+  // Modifiers
+  Alt,
+  CapsLock,
+  Control,
+  Meta,
+  NumLock,
+  Shift,
+
+  // Whitespace
+  Enter,
+  Tab,
+  Space,
+
+  // Navigation
+  ArrowDown,
+  ArrowLeft,
+  ArrowRight,
+  ArrowUp,
+  End,
+  Home,
+  PageDown,
+  PageUp,
+
+  // UI
+  Escape,
+
+  // Editing keys
+  Backspace,
+
+  // Function keys
+  F1,
+  F2,
+  F3,
+  F4,
+  F5,
+  F6,
+  F7,
+  F8,
+  F9,
+  F10,
+  F11,
+  F12,
+  F13,
+  F14,
+  F15,
+  F16,
+  F17,
+  F18,
+  F19,
+  F20,
+
+  // Other keys, includes the raw code provided by the operating system
+  Other(i32),
+}

espanso/src/engine/event/matches_detected.rs

@@ -0,0 +1,32 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use std::collections::HashMap;
+
+#[derive(Debug, Clone, PartialEq)]
+pub struct MatchesDetectedEvent {
+  pub results: Vec<MatchResult>,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub struct MatchResult {
+  pub id: i32,
+  pub trigger: String,
+  pub vars: HashMap<String, String>,
+}

espanso/src/engine/event/mod.rs

@@ -0,0 +1,36 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+pub mod keyboard;
+pub mod inject;
+pub mod matches_detected;
+
+#[derive(Debug)]
+pub enum Event {
+  NOOP,
+  
+  // Inputs
+  Keyboard(keyboard::KeyboardEvent),
+
+  // Internal
+  MatchesDetected(matches_detected::MatchesDetectedEvent),
+
+  // Effects
+  TextInject(inject::TextInjectEvent),
+}

espanso/src/engine/funnel/default.rs

@@ -0,0 +1,56 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use crossbeam::channel::Select;
+
+use super::{Funnel, FunnelResult, Source};
+
+pub struct DefaultFunnel {
+  sources: Vec<Box<dyn Source>>,
+}
+
+impl DefaultFunnel {
+  pub fn new(sources: Vec<Box<dyn Source>>) -> Self {
+    Self {
+      sources
+    }
+  }
+}
+
+impl Funnel for DefaultFunnel {
+  fn receive(&self) -> FunnelResult {
+    let mut select = Select::new();
+
+    // First register all the sources to the select operation
+    for source in self.sources.iter() {
+      source.register(&select);
+    }
+
+    // Wait for the first source (blocking operation)
+    let op = select.select();    
+    let source = self
+      .sources
+      .get(op.index())
+      .expect("invalid source index returned by select operation");
+
+    // Receive (and convert) the event
+    let event = source.receive(&op);
+    FunnelResult::Event(event)
+  }
+}

espanso/src/engine/funnel/mod.rs

@@ -0,0 +1,44 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use crossbeam::{channel::Select, channel::SelectedOperation};
+
+use self::default::DefaultFunnel;
+
+use super::Event;
+
+mod default;
+
+pub trait Source {
+  fn register(&self, select: &Select) -> i32;
+  fn receive(&self, select: &SelectedOperation) -> Event;
+}
+
+pub trait Funnel {
+  fn receive(&self) -> FunnelResult;
+}
+
+pub enum FunnelResult {
+  Event(Event),
+  EndOfStream,
+}
+
+pub fn default(sources: Vec<Box<dyn Source>>) -> impl Funnel {
+  DefaultFunnel::new(sources)
+}

espanso/src/engine/mod.rs

@@ -0,0 +1,68 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use log::{debug, trace};
+use std::collections::VecDeque;
+
+use self::{
+  dispatch::Dispatcher,
+  event::Event,
+  process::Processor,
+  funnel::{Funnel, FunnelResult},
+};
+
+pub mod dispatch;
+pub mod event;
+pub mod process;
+pub mod funnel;
+
+pub struct Engine<TFunnel: Funnel, TProcessor: Processor, TDispatcher: Dispatcher> {
+  funnel: TFunnel,
+  processor: TProcessor,
+  dispatcher: TDispatcher,
+}
+
+impl <TFunnel: Funnel, TProcessor: Processor, TDispatcher: Dispatcher> Engine<TFunnel, TProcessor, TDispatcher> {
+  pub fn new(funnel: TFunnel, processor: TProcessor, dispatcher: TDispatcher) -> Self {
+    Self {
+      funnel,
+      processor,
+      dispatcher,
+    }
+  }
+
+  pub fn run(&mut self) {
+    loop {
+      match self.funnel.receive() {
+        FunnelResult::Event(event) => {
+          trace!("received event from stream: {:?}", event);
+          
+          let processed_events = self.processor.process(event);
+          for event in processed_events {
+            self.dispatcher.dispatch(event);
+          }
+        } 
+        FunnelResult::EndOfStream => {
+          debug!("end of stream received");
+          break;
+        }
+      }
+    }
+  }
+}

espanso/src/engine/process/default.rs

@@ -0,0 +1,78 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use super::{Event, Matcher, Middleware, Processor, middleware::matcher::MatchMiddleware};
+use std::collections::VecDeque;
+
+pub struct DefaultProcessor {
+  event_queue: VecDeque<Event>,
+  middleware: Vec<Box<dyn Middleware>>,
+}
+
+impl DefaultProcessor {
+  pub fn new<MatcherState: 'static>(matchers: Vec<Box<dyn Matcher<MatcherState>>>) -> Self {
+    Self {
+      event_queue: VecDeque::new(),
+      middleware: vec![
+        Box::new(MatchMiddleware::new(matchers)),
+      ]
+    }
+  }
+
+  fn process_one(&mut self) -> Option<Event> {
+    if let Some(event) = self.event_queue.pop_back() {
+      let mut current_event = event;
+      
+      let mut current_queue = VecDeque::new();
+      let dispatch = |event: Event| {
+        // TODO: add tracing information
+        current_queue.push_front(event);
+      };
+
+      for middleware in self.middleware.iter() {
+        // TODO: add tracing information
+        current_event = middleware.next(current_event, &dispatch);
+      }
+
+      while let Some(event) = current_queue.pop_back() {
+        self.event_queue.push_front(event);
+      }
+
+      Some(current_event)
+    } else {
+      None
+    }
+  }
+}
+
+impl Processor for DefaultProcessor {
+  fn process(&mut self, event: Event) -> Vec<Event> {
+    self.event_queue.push_front(event);
+
+    let mut processed_events = Vec::new();
+
+    while !self.event_queue.is_empty() {
+      if let Some(event) = self.process_one() {
+        processed_events.push(event);
+      }
+    }
+
+    processed_events
+  }
+}

espanso/src/engine/process/middleware/matcher.rs

@@ -0,0 +1,133 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use log::trace;
+use std::{cell::RefCell, collections::VecDeque};
+
+use super::super::Middleware;
+use crate::engine::{event::{Event, keyboard::{Key, Status}, matches_detected::{MatchResult, MatchesDetectedEvent}}, process::{Matcher, MatcherEvent}};
+
+const MAX_HISTORY: usize = 3; // TODO: get as parameter
+
+pub struct MatchMiddleware<State> {
+  matchers: Vec<Box<dyn Matcher<State>>>,
+
+  matcher_states: RefCell<VecDeque<Vec<State>>>,
+}
+
+impl<State> MatchMiddleware<State> {
+  pub fn new(matchers: Vec<Box<dyn Matcher<State>>>) -> Self {
+    Self {
+      matchers,
+      matcher_states: RefCell::new(VecDeque::new()),
+    }
+  }
+}
+
+impl<State> Middleware for MatchMiddleware<State> {
+  fn next(&self, event: Event, _: &dyn FnMut(Event)) -> Event {
+    let mut matcher_states = self.matcher_states.borrow_mut();
+    let prev_states = if !matcher_states.is_empty() {
+      matcher_states.get(matcher_states.len() - 1)
+    } else {
+      None
+    };
+
+    if let Event::Keyboard(keyboard_event) = &event {
+      // Backspace handling
+      if keyboard_event.key == Key::Backspace {
+        trace!("popping the last matcher state");
+        matcher_states.pop_back();
+        return event;
+      }
+
+      // Some keys (such as the arrow keys) prevent espanso from building
+      // an accurate key buffer, so we need to invalidate it.
+      if is_invalidating_key(&keyboard_event.key) {
+        matcher_states.clear();
+        return event;
+      }
+    }
+
+    // TODO: test if the matcher detects a word match when the states are cleared (probably not :( )
+
+    let mut all_results = Vec::new();
+
+    if let Some(matcher_event) = convert_to_matcher_event(&event) {
+      let mut new_states = Vec::new();
+      for (i, matcher) in self.matchers.iter().enumerate() {
+        let prev_state = prev_states.and_then(|states| states.get(i));
+
+        let (state, results) = matcher.process(prev_state, &matcher_event);
+        all_results.extend(results);
+
+        new_states.push(state);
+      }
+
+      matcher_states.push_back(new_states);
+      if matcher_states.len() > MAX_HISTORY {
+        matcher_states.pop_front();
+      }
+
+      if !all_results.is_empty() {
+        return Event::MatchesDetected(MatchesDetectedEvent {
+          results: all_results.into_iter().map(|result | {
+            MatchResult {
+              id: result.id,
+              trigger: result.trigger,
+              vars: result.vars,
+            }
+          }).collect()
+        })
+      }
+    }
+
+    event
+  }
+}
+
+fn convert_to_matcher_event(event: &Event) -> Option<MatcherEvent> {
+  if let Event::Keyboard(keyboard_event) = event {
+    if keyboard_event.status == Status::Pressed {
+      return Some(MatcherEvent::Key {
+        key: keyboard_event.key.clone(),
+        chars: keyboard_event.value.clone(),
+      });
+    }
+  }
+
+  // TODO: mouse event should act as separator
+
+  None
+}
+
+fn is_invalidating_key(key: &Key) -> bool {
+  match key {
+    Key::ArrowDown => true,
+    Key::ArrowLeft => true,
+    Key::ArrowRight => true,
+    Key::ArrowUp => true,
+    Key::End => true,
+    Key::Home => true,
+    Key::PageDown => true,
+    Key::PageUp => true,
+    Key::Escape => true,
+    _ => false,
+  }
+}

espanso/src/engine/process/middleware/mod.rs

@@ -0,0 +1,20 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+pub mod matcher;

espanso/src/engine/process/mod.rs

@@ -0,0 +1,56 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+
+use std::collections::HashMap;
+
+use super::{Event, event::keyboard::Key};
+
+mod middleware;
+mod default;
+
+pub trait Middleware {
+  fn next(&self, event: Event, dispatch: &dyn FnMut(Event)) -> Event;
+}
+
+pub trait Processor {
+  fn process(&mut self, event: Event) -> Vec<Event>;
+}
+
+// Dependency inversion entities
+
+pub trait Matcher<State> {
+  fn process(&self, prev_state: Option<&State>, event: &MatcherEvent) -> (State, Vec<MatchResult>);
+}
+
+pub enum MatcherEvent {
+  Key { key: Key, chars: Option<String> },
+  VirtualSeparator,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub struct MatchResult {
+  id: i32,
+  trigger: String,
+  vars: HashMap<String, String>,
+}
+
+pub fn default<MatcherState: 'static>(matchers: Vec<Box<dyn Matcher<MatcherState>>>) -> impl Processor {
+  default::DefaultProcessor::new(matchers)
+}

espanso/src/main.rs

@@ -28,7 +28,6 @@ use simplelog::{CombinedLogger, ConfigBuilder, LevelFilter, TermLogger, Terminal
 mod cli;
 mod engine;
 mod logging;
-mod util;
 
 const VERSION: &str = env!("CARGO_PKG_VERSION");
 const LOG_FILE_NAME: &str = "espanso.log";
@@ -37,6 +36,7 @@ lazy_static! {
   static ref CLI_HANDLERS: Vec<CliModule> = vec![
     cli::path::new(),
     cli::log::new(),
+    cli::worker::new(),
   ];
 }
 
@@ -170,19 +170,19 @@ fn main() {
         //     )
         // )
         // Package manager
-        .subcommand(SubCommand::with_name("package")
+        // .subcommand(SubCommand::with_name("package")
-            .about("Espanso package manager commands")
+        //     .about("Espanso package manager commands")
-            .subcommand(install_subcommand.clone())
+        //     .subcommand(install_subcommand.clone())
-            .subcommand(uninstall_subcommand.clone())
+        //     .subcommand(uninstall_subcommand.clone())
-            .subcommand(SubCommand::with_name("list")
+        //     .subcommand(SubCommand::with_name("list")
-                .about("List all installed packages")
+        //         .about("List all installed packages")
-                .arg(Arg::with_name("full")
+        //         .arg(Arg::with_name("full")
-                    .help("Print all package info")
+        //             .help("Print all package info")
-                    .long("full")))
+        //             .long("full")))
 
-            .subcommand(SubCommand::with_name("refresh")
+        //     .subcommand(SubCommand::with_name("refresh")
-                .about("Update espanso package index"))
+        //         .about("Update espanso package index"))
-        )
+        // )
         .subcommand(SubCommand::with_name("worker")
             .setting(AppSettings::Hidden)
             .arg(Arg::with_name("reload")
@@ -190,9 +190,9 @@ fn main() {
                 .long("reload")
                 .required(false)
                 .takes_value(false))
-        )
+        );
-        .subcommand(install_subcommand)
+        // .subcommand(install_subcommand)
-        .subcommand(uninstall_subcommand);
+        // .subcommand(uninstall_subcommand);
 
   // TODO: explain that the start and restart commands are only meaningful
   // when using the system daemon manager on macOS and Linux