espanso/espanso-engine/src/process/middleware/undo.rs
2021-08-15 11:10:13 +02:00

116 lines
3.4 KiB
Rust

/*
* 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::cell::RefCell;
use super::super::Middleware;
use crate::event::{
input::{Key, Status},
internal::{TextFormat, UndoEvent},
Event, EventType,
};
pub trait UndoEnabledProvider {
fn is_undo_enabled(&self) -> bool;
}
pub struct UndoMiddleware<'a> {
undo_enabled_provider: &'a dyn UndoEnabledProvider,
record: RefCell<Option<InjectionRecord>>,
}
impl<'a> UndoMiddleware<'a> {
pub fn new(undo_enabled_provider: &'a dyn UndoEnabledProvider) -> Self {
Self {
undo_enabled_provider,
record: RefCell::new(None),
}
}
}
impl<'a> Middleware for UndoMiddleware<'a> {
fn name(&self) -> &'static str {
"undo"
}
fn next(&self, event: Event, _: &mut dyn FnMut(Event)) -> Event {
let mut record = self.record.borrow_mut();
if let EventType::TriggerCompensation(m_event) = &event.etype {
*record = Some(InjectionRecord {
id: Some(event.source_id),
trigger: Some(m_event.trigger.clone()),
..Default::default()
});
} else if let EventType::Rendered(m_event) = &event.etype {
if let TextFormat::Plain = m_event.format {
if let Some(record) = &mut *record {
if record.id == Some(event.source_id) {
record.injected_text = Some(m_event.body.clone());
record.match_id = Some(m_event.match_id);
}
}
}
} else if let EventType::Keyboard(m_event) = &event.etype {
if m_event.status == Status::Pressed {
if m_event.key == Key::Backspace {
if let Some(record) = (*record).take() {
if let (Some(trigger), Some(injected_text), Some(match_id)) =
(record.trigger, record.injected_text, record.match_id)
{
if self.undo_enabled_provider.is_undo_enabled() {
return Event::caused_by(
event.source_id,
EventType::Undo(UndoEvent {
match_id,
trigger,
replace: injected_text,
}),
);
}
}
}
}
*record = None;
}
} else if let EventType::Mouse(_) = &event.etype {
// Any mouse event invalidates the undo feature, as it could
// represent a change in application
*record = None;
} else if let EventType::CursorHintCompensation(_) = &event.etype {
// Cursor hints invalidate the undo feature, as it would be pretty
// complex to determine which delete operations should be performed.
// This might change in the future.
*record = None;
}
event
}
}
#[derive(Default)]
struct InjectionRecord {
id: Option<u32>,
match_id: Option<i32>,
trigger: Option<String>,
injected_text: Option<String>,
}
// TODO: test