Add backspace corrections

src/config.rs

@@ -7,7 +7,6 @@ use std::fs::File;
 use std::io::Read;
 use serde::{Serialize, Deserialize};
 use crate::keyboard::KeyModifier;
-use crate::keyboard::KeyModifier::*;
 
 // TODO: add documentation link
 const DEFAULT_CONFIG_FILE_CONTENT : &str = include_str!("res/config.yaml");
@@ -18,6 +17,10 @@ fn default_toggle_interval() -> u32 {
     230
 }
 
+fn default_backspace_limit() -> i32 {
+    3
+}
+
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct Configs {
     #[serde(default)]
@@ -26,6 +29,9 @@ pub struct Configs {
     #[serde(default = "default_toggle_interval")]
     pub toggle_interval: u32,
 
+    #[serde(default = "default_backspace_limit")]
+    pub backspace_limit: i32,
+
     pub matches: Vec<Match>
 }
 

src/keyboard/windows.rs

@@ -1,4 +1,3 @@
-use std::thread;
 use std::sync::mpsc;
 use widestring::{U16CString};
 use crate::keyboard::{KeyEvent, KeyModifier};

src/matcher/scrolling.rs

@@ -4,11 +4,12 @@ use crate::keyboard::KeyModifier;
 use crate::config::Configs;
 use crate::keyboard::KeyModifier::BACKSPACE;
 use std::time::SystemTime;
+use std::collections::VecDeque;
 
 pub struct ScrollingMatcher<'a, R> where R: MatchReceiver{
     configs: Configs,
     receiver: R,
-    current_set: RefCell<Vec<MatchEntry<'a>>>,
+    current_set_queue: RefCell<VecDeque<Vec<MatchEntry<'a>>>>,
     toggle_press_time: RefCell<SystemTime>,
     is_enabled: RefCell<bool>,
 }
@@ -25,7 +26,7 @@ impl <'a, R> super::Matcher<'a> for ScrollingMatcher<'a, R> where R: MatchReceiv
             return;
         }
 
-        let mut current_set = self.current_set.borrow_mut();
+        let mut current_set_queue = self.current_set_queue.borrow_mut();
 
         let new_matches: Vec<MatchEntry> = self.configs.matches.iter()
             .filter(|&x| x.trigger.chars().nth(0).unwrap() == c)
@@ -33,27 +34,40 @@ impl <'a, R> super::Matcher<'a> for ScrollingMatcher<'a, R> where R: MatchReceiv
             .collect();
         // TODO: use an associative structure to improve the efficiency of this first "new_matches" lookup.
 
-        let old_matches: Vec<MatchEntry> = (*current_set).iter()
-            .filter(|&x| {
-                x._match.trigger[x.start..].chars().nth(0).unwrap() == c
-            })
-            .map(|x | MatchEntry{start: x.start+1, _match: &x._match})
-            .collect();
+        let combined_matches: Vec<MatchEntry> = match current_set_queue.back() {
+            Some(last_matches) => {
+                let mut updated: Vec<MatchEntry> = last_matches.iter()
+                    .filter(|&x| {
+                        x._match.trigger[x.start..].chars().nth(0).unwrap() == c
+                    })
+                    .map(|x | MatchEntry{start: x.start+1, _match: &x._match})
+                    .collect();
 
-        (*current_set) = old_matches;
-        (*current_set).extend(new_matches);
+                updated.extend(new_matches);
+                updated
+            },
+            None => {new_matches},
+        };
 
         let mut found_match = None;
 
-        for entry in (*current_set).iter() {
+        for entry in combined_matches.iter() {
             if entry.start == entry._match.trigger.len() {
                 found_match = Some(entry._match);
                 break;
             }
         }
 
+        current_set_queue.push_back(combined_matches);
+
+        if current_set_queue.len() as i32 > (self.configs.backspace_limit + 1) {
+            current_set_queue.pop_front();
+        }
+
         if let Some(_match) = found_match {
-            (*current_set).clear();
+            if let Some(last) = current_set_queue.back_mut() {
+                last.clear();
+            }
             self.receiver.on_match(_match);
         }
     }
@@ -67,7 +81,7 @@ impl <'a, R> super::Matcher<'a> for ScrollingMatcher<'a, R> where R: MatchReceiv
                     *is_enabled = !(*is_enabled);
 
                     if !*is_enabled {
-                        self.current_set.borrow_mut().clear();
+                        self.current_set_queue.borrow_mut().clear();
                     }
 
                     println!("Enabled {}", *is_enabled);
@@ -76,18 +90,23 @@ impl <'a, R> super::Matcher<'a> for ScrollingMatcher<'a, R> where R: MatchReceiv
 
             (*toggle_press_time) = SystemTime::now();
         }
+
+        // Backspace handling, basically "rewinding history"
+        if m == BACKSPACE {
+            let mut current_set_queue = self.current_set_queue.borrow_mut();
+            current_set_queue.pop_back();
+        }
     }
 }
-
 impl <'a, R> ScrollingMatcher<'a, R> where R: MatchReceiver {
     pub fn new(configs: Configs, receiver: R) -> ScrollingMatcher<'a, R> {
-        let current_set = RefCell::new(Vec::new());
+        let current_set_queue = RefCell::new(VecDeque::new());
         let toggle_press_time = RefCell::new(SystemTime::now());
 
         ScrollingMatcher{
             configs,
             receiver,
-            current_set,
+            current_set_queue,
             toggle_press_time,
             is_enabled: RefCell::new(true)
         }