Added buffer insertion and deletion

rustfmt.toml

@@ -1 +1,2 @@
 max_width = 120
+use_small_heuristics = "Max"

src/editor/editor.rs

@@ -1,21 +1,16 @@
 use color_eyre::Report;
-use crossterm::{
-    cursor,
-    event::{poll, read, Event, KeyEvent},
-    execute, queue, style,
-    terminal::{self, ClearType},
-};
+use crossterm::event::{poll, read, Event, KeyCode, KeyEvent, KeyModifiers};
 use std::{
     fs::File,
-    io::{self, BufRead, BufReader, Write},
+    io::{BufRead, BufReader},
     sync::mpsc,
     time::{Duration, Instant},
 };
 use tokio::runtime::Runtime;
 
-use super::{default_keybinds, Keymap};
+use crate::util::{Display, Keymap};
 
-#[derive(Debug, Eq, PartialEq, Hash)]
+#[derive(Eq, PartialEq, Hash)]
 pub enum Mode {
     NORMAL,
     COMMAND,
@@ -23,54 +18,35 @@ pub enum Mode {
     VISUAL,
 }
 
-#[derive(Debug)]
 pub struct Editor {
     pub(crate) buffer: Vec<String>,
+    pub(crate) command: String,
     pub(crate) dirty: bool,
     pub(crate) stop: bool,
 
     pub(crate) mode: Mode,
 
-    pub(crate) size: (u16, u16),
-    pub(crate) cursor: (u16, u16),
-    pub(crate) offset: (u16, u16),
+    pub(crate) display: Display,
 
     pub(crate) keymap: Keymap,
     pub(crate) last_key_time: Instant,
-
-    pub(crate) out: io::Stdout,
-}
-
-impl Drop for Editor {
-    fn drop(&mut self) {
-        let _ = execute!(self.out, style::ResetColor, terminal::LeaveAlternateScreen);
-    }
 }
 
 impl Editor {
     pub fn new() -> Self {
-        let mut keymap = Keymap::new();
-        default_keybinds(&mut keymap);
-
-        let mut editor = Self {
+        Self {
             buffer: vec![String::new()],
+            command: String::new(),
             dirty: true,
             stop: false,
 
             mode: Mode::NORMAL,
 
-            size: terminal::size().unwrap(),
-            cursor: (0, 0),
-            offset: (0, 0),
+            display: Display::new(),
 
-            keymap,
+            keymap: Keymap::new(),
             last_key_time: Instant::now(),
-
-            out: io::stdout(),
-        };
-
-        let _ = execute!(editor.out, terminal::EnterAlternateScreen);
-        editor
+        }
     }
 
     pub fn load_file(&mut self, filename: &str) {
@@ -100,23 +76,22 @@ impl Editor {
             tokio::spawn(async move {
                 Editor::key_event_listener(tx).await;
             });
+        });
 
-            while !self.stop {
-                self.handle_key_event(&mut rx).await?;
-                self.render().await?;
+        while !self.stop {
+            self.handle_key_event(&mut rx)?;
+
+            if self.dirty {
+                self.display.render(&self.buffer, &self.command, &self.mode)?;
+                self.dirty = false;
             }
+        }
 
-            self.buffer.push("This is outside main loop".to_string());
-            self.dirty = true;
-            self.render().await?;
-
-            Ok(())
-        })
+        Ok(())
     }
 
-    async fn handle_key_event(&mut self, rx: &mut mpsc::Receiver<KeyEvent>) -> Result<(), Report> {
+    fn handle_key_event(&mut self, rx: &mut mpsc::Receiver<KeyEvent>) -> Result<(), Report> {
         if self.last_key_time.elapsed().as_millis() > 1000 && !self.keymap.is_empty() {
-            self.buffer.push("TIMEOUT".to_string());
             self.execute_keymap_action()?;
             self.dirty = true;
         }
@@ -132,22 +107,69 @@ impl Editor {
             unresolved = self.keymap.traverse(&self.mode, event)?;
         }
 
-        if let Some(unresolved) = unresolved {
-            self.buffer.push(format!(
-                "{} {:?} {:?}",
-                unresolved.code, unresolved.modifiers, self.last_key_time
-            ));
-        }
-
         if self.keymap.is_leaf() {
             self.execute_keymap_action()?;
         }
 
+        if let Some(unresolved) = unresolved {
+            if !unresolved.modifiers.intersects(KeyModifiers::ALT | KeyModifiers::CONTROL) {
+                self.handle_unresolved_key_event(unresolved);
+            }
+        }
+
         self.last_key_time = Instant::now();
         self.dirty = true;
         Ok(())
     }
 
+    fn handle_unresolved_key_event(&mut self, unresolved: KeyEvent) {
+        match self.mode {
+            Mode::COMMAND => {
+                if let KeyCode::Char(c) = unresolved.code {
+                    self.command.push(c);
+                } else if unresolved.code == KeyCode::Backspace {
+                    self.command.pop();
+                }
+            }
+            Mode::INSERT => match unresolved.code {
+                KeyCode::Char(c) => {
+                    let (x, y) = self.display.cursor.position;
+                    self.buffer[y as usize].insert(x as usize, c);
+                    self.display.move_cursor((1, 0), &self.buffer);
+                }
+                KeyCode::Enter => {
+                    let (x, y) = self.display.cursor.position;
+                    let remaining = self.buffer[y as usize].split_off(x as usize);
+                    self.buffer.insert((y + 1) as usize, remaining);
+                    self.display.move_cursor((-(x as i16), 1), &self.buffer)
+                }
+                KeyCode::Delete => {
+                    let (x, y) = self.display.cursor.position;
+                    if x < self.buffer[y as usize].len() as u16 {
+                        self.buffer[y as usize].remove(x as usize);
+                    } else if y + 1 < self.buffer.len() as u16 {
+                        let next_line = self.buffer.remove((y + 1) as usize);
+                        self.buffer[y as usize].push_str(&next_line);
+                    }
+                }
+                KeyCode::Backspace => {
+                    let (x, y) = self.display.cursor.position;
+                    if x > 0 {
+                        self.buffer[y as usize].remove((x - 1) as usize);
+                        self.display.move_cursor((-1, 0), &self.buffer);
+                    } else if y > 0 {
+                        let prev_line_len = self.buffer[(y - 1) as usize].len() as u16;
+                        let current_line = self.buffer.remove(y as usize);
+                        self.buffer[(y - 1) as usize].push_str(&current_line);
+                        self.display.move_cursor((prev_line_len as i16, -1), &self.buffer);
+                    }
+                }
+                _ => {}
+            },
+            _ => {}
+        }
+    }
+
     fn execute_keymap_action(&mut self) -> Result<(), Report> {
         if let Some(action) = self.keymap.get_action() {
             action.borrow_mut()(self)?;
@@ -157,44 +179,6 @@ impl Editor {
         Ok(())
     }
 
-    async fn render(&mut self) -> Result<(), Report> {
-        if !self.dirty {
-            return Ok(());
-        }
-
-        queue!(
-            self.out,
-            style::ResetColor,
-            terminal::Clear(ClearType::All),
-            cursor::MoveTo(0, 0)
-        )?;
-
-        let max_lines = self.size.1 as usize;
-
-        let render = &self.buffer[self.offset.1 as usize..]
-            .iter()
-            .take(max_lines)
-            .collect::<Vec<_>>();
-
-        for line in render {
-            queue!(self.out, style::Print(line), cursor::MoveToNextLine(1))?;
-        }
-
-        let rendered_lines = render.len();
-        if rendered_lines < max_lines {
-            let empty_lines = max_lines - rendered_lines;
-            for _ in 0..empty_lines {
-                queue!(self.out, style::Print("~"), cursor::MoveToNextLine(1))?;
-            }
-        }
-
-        queue!(self.out, cursor::MoveTo(self.cursor.0, self.cursor.1))?;
-        self.out.flush()?;
-
-        self.dirty = false;
-        Ok(())
-    }
-
     async fn key_event_listener(tx: mpsc::Sender<KeyEvent>) {
         loop {
             if !poll(Duration::from_millis(10)).unwrap() {

src/editor/keybinds.rs

@@ -1,13 +0,0 @@
-use super::{Keymap, Mode};
-use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
-
-pub fn default_keybinds(keymap: &mut Keymap) {
-    keymap.add_keybind(
-        vec![Mode::NORMAL],
-        vec![
-            KeyEvent::new(KeyCode::Char('w'), KeyModifiers::CONTROL),
-            KeyEvent::new(KeyCode::Char('q'), KeyModifiers::CONTROL),
-        ],
-        |editor| Ok(editor.stop = true),
-    );
-}

src/editor/mod.rs

@@ -1,9 +1,5 @@
 mod editor;
-mod keybinds;
-mod keymap;
 
-pub(crate) use self::editor::{ControlCode, Mode};
-pub(crate) use self::keybinds::default_keybinds;
-pub(crate) use self::keymap::Keymap;
+pub(crate) use self::editor::Mode;
 
 pub use self::editor::Editor;

src/macros.rs

@@ -0,0 +1,130 @@
+use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
+
+use crate::editor::{Editor, Mode};
+
+macro_rules! add_keybind {
+    ($editor:expr, $modes:expr, $sequence:expr, $action:expr) => {
+        $editor.keymap.add_keybind(
+            add_keybind!(@parse_modes $modes),
+            add_keybind!(@parse_keys $sequence),
+            $action,
+        );
+    };
+
+    (@parse_keys $keyseq:expr) => {{
+        let mut keys = Vec::new();
+        let mut chars = $keyseq.chars().peekable();
+
+        while let Some(c) = chars.next() {
+            if c == '<' {
+                let mut key_name = String::new();
+                while let Some(&peek) = chars.peek() {
+                    if peek == '>' {
+                        chars.next();
+                        break;
+                    }
+                    key_name.push(chars.next().unwrap());
+                }
+
+                let (modifiers, key) = if let Some(split_idx) = key_name.find('-') {
+                    let (modifier, key) = key_name.split_at(split_idx);
+                    (modifier, &key[1..].to_string())
+                } else {
+                    ("", &key_name)
+                };
+
+                let modifiers = match modifiers {
+                    "C" => KeyModifiers::CONTROL,
+                    "S" => KeyModifiers::SHIFT,
+                    "A" => KeyModifiers::ALT,
+                    _ => KeyModifiers::NONE,
+                };
+
+                let key_event = match key.as_str() {
+                    "BS" => KeyEvent::new(KeyCode::Backspace, modifiers),
+                    "Tab" => KeyEvent::new(KeyCode::Tab, modifiers),
+                    "CR" | "Enter" | "Return" => KeyEvent::new(KeyCode::Enter, modifiers),
+                    "Esc" => KeyEvent::new(KeyCode::Esc, modifiers),
+                    "Space" => KeyEvent::new(KeyCode::Char(' '), modifiers),
+                    "Up" => KeyEvent::new(KeyCode::Up, modifiers),
+                    "Down" => KeyEvent::new(KeyCode::Down, modifiers),
+                    "Left" => KeyEvent::new(KeyCode::Left, modifiers),
+                    "Right" => KeyEvent::new(KeyCode::Right, modifiers),
+                    "Insert" => KeyEvent::new(KeyCode::Insert, modifiers),
+                    "Del" => KeyEvent::new(KeyCode::Delete, modifiers),
+                    "Home" => KeyEvent::new(KeyCode::Home, modifiers),
+                    "End" => KeyEvent::new(KeyCode::End, modifiers),
+                    "PageUp" => KeyEvent::new(KeyCode::PageUp, modifiers),
+                    "PageDown" => KeyEvent::new(KeyCode::PageDown, modifiers),
+                    key if key.starts_with('F') && key[1..].parse::<u8>().is_ok() => {
+                        let f_num = key[1..].parse::<u8>().unwrap();
+                        KeyEvent::new(KeyCode::F(f_num), modifiers)
+                    }
+                    key if key.len() == 1 => {
+                        KeyEvent::new(KeyCode::Char(key.chars().next().unwrap()), modifiers)
+                    }
+                    _ => panic!("Unknown key: {}", key),
+                };
+
+                keys.push(key_event);
+            } else {
+                keys.push(KeyEvent::new(KeyCode::Char(c), KeyModifiers::NONE));
+            }
+        }
+
+        keys
+    }};
+
+    (@parse_modes $modes:expr) => {{
+        $modes
+            .chars()
+            .filter_map(|c| match c {
+                'n' => Some(Mode::NORMAL),
+                'v' => Some(Mode::VISUAL),
+                'c' => Some(Mode::COMMAND),
+                'i' => Some(Mode::INSERT),
+                _ => None,
+            })
+            .collect::<Vec<_>>()
+    }};
+}
+
+pub fn default_keybinds(editor: &mut Editor) {
+    add_keybind!(editor, "ni", "<C-w><C-q>", |e| Ok(e.stop = true));
+
+    add_keybind!(editor, "n", "k", |e| {
+        e.display.move_cursor((0, -1), &e.buffer);
+        Ok(())
+    });
+
+    add_keybind!(editor, "n", "j", |e| {
+        e.display.move_cursor((0, 1), &e.buffer);
+        Ok(())
+    });
+
+    add_keybind!(editor, "n", "h", |e| {
+        e.display.move_cursor((-1, 0), &e.buffer);
+        Ok(())
+    });
+
+    add_keybind!(editor, "n", "l", |e| {
+        e.display.move_cursor((1, 0), &e.buffer);
+        Ok(())
+    });
+
+    add_keybind!(editor, "n", "i", |e| {
+        e.mode = Mode::INSERT;
+        Ok(())
+    });
+
+    add_keybind!(editor, "n", ":", |e| {
+        e.mode = Mode::COMMAND;
+        Ok(())
+    });
+
+    add_keybind!(editor, "ic", "<Esc>", |e| {
+        e.mode = Mode::NORMAL;
+        e.command.clear();
+        Ok(())
+    });
+}

src/main.rs

@@ -1,13 +1,16 @@
 mod editor;
+mod util;
 
-use std::time::Instant;
+#[macro_use]
+mod macros;
 
 use clap::Parser;
 use color_eyre::Report;
 use crossterm::terminal;
+use tracing_subscriber::EnvFilter;
 
 use editor::Editor;
-use tracing_subscriber::EnvFilter;
+use macros::default_keybinds;
 
 struct RawModeGuard;
 impl Drop for RawModeGuard {
@@ -25,9 +28,7 @@ fn setup() -> Result<(), Report> {
     if std::env::var("RUST_LOG").is_err() {
         std::env::set_var("RUST_LOG", "info")
     }
-    tracing_subscriber::fmt::fmt()
-        .with_env_filter(EnvFilter::from_default_env())
-        .init();
+    tracing_subscriber::fmt::fmt().with_env_filter(EnvFilter::from_default_env()).init();
 
     Ok(())
 }
@@ -49,6 +50,8 @@ fn main() -> Result<(), Report> {
         let _raw_mode_guard = RawModeGuard;
 
         let mut editor = Editor::new();
+        default_keybinds(&mut editor);
+
         if let Some(filename) = &args.filename {
             editor.load_file(filename);
         };

src/util/display.rs

@@ -0,0 +1,151 @@
+use color_eyre::Report;
+use crossterm::{
+    cursor::{self, SetCursorStyle},
+    execute, queue,
+    style::{self, Stylize},
+    terminal::{self, ClearType},
+};
+use std::io::{self, Write};
+
+use crate::editor::Mode;
+
+pub struct Display {
+    size: (u16, u16),
+    offset: (u16, u16),
+
+    pub(crate) cursor: Cursor,
+
+    pub(crate) out: io::Stdout,
+}
+
+pub struct Cursor {
+    pub(crate) position: (u16, u16),
+    pub(crate) max_column: u16,
+}
+
+impl Cursor {
+    pub fn new() -> Self {
+        Self { position: (0, 0), max_column: 0 }
+    }
+
+    fn move_by(&mut self, delta: (i16, i16), buffer: &Vec<String>) {
+        let saturate = |pos: u16, delta: i16| {
+            if delta.is_negative() {
+                pos.saturating_sub(delta.abs() as u16)
+            } else {
+                pos.saturating_add(delta as u16)
+            }
+        };
+
+        let (mut x, mut y) = self.position;
+        let (dx, dy) = delta;
+
+        if dx != 0 {
+            x = saturate(x, dx);
+            self.max_column = x;
+        }
+
+        if dy != 0 {
+            y = saturate(y, dy);
+        }
+
+        self.position = (x, y);
+        self.validate_cursor(buffer);
+    }
+
+    fn move_x(&mut self, new_x: u16) {
+        self.position.0 = new_x;
+    }
+
+    fn move_y(&mut self, new_y: u16) {
+        self.position.1 = new_y;
+    }
+
+    fn validate_cursor(&mut self, buffer: &Vec<String>) {
+        let (_x, y) = self.position;
+
+        if y >= buffer.len() as u16 {
+            self.move_y(buffer.len().saturating_sub(1) as u16);
+        }
+
+        let line_len = buffer[self.position.1 as usize].len() as u16;
+        self.move_x(self.max_column.min(line_len));
+    }
+}
+
+impl Drop for Display {
+    fn drop(&mut self) {
+        let _ = execute!(self.out, style::ResetColor, terminal::LeaveAlternateScreen);
+    }
+}
+
+impl Display {
+    pub fn new() -> Self {
+        let mut display =
+            Self { size: terminal::size().unwrap(), offset: (0, 0), cursor: Cursor::new(), out: io::stdout() };
+
+        let _ = execute!(display.out, terminal::EnterAlternateScreen);
+
+        display
+    }
+
+    pub fn move_cursor(&mut self, delta: (i16, i16), buffer: &Vec<String>) {
+        self.cursor.move_by(delta, buffer);
+    }
+
+    pub fn render(&mut self, buffer: &Vec<String>, command: &String, mode: &Mode) -> Result<(), Report> {
+        queue!(self.out, style::ResetColor, terminal::Clear(ClearType::All), cursor::MoveTo(0, 0))?;
+
+        let mut max_lines = self.size.1 as usize;
+        if !command.is_empty() {
+            max_lines -= 1;
+        }
+
+        let max_columns = self.size.0 as usize;
+
+        let render = buffer[self.offset.1 as usize..]
+            .iter()
+            .take(max_lines)
+            .map(|line| {
+                if line.len() > self.offset.0 as usize {
+                    let start = self.offset.0 as usize;
+                    let end = (start + max_columns).min(line.len());
+                    &line[start..end]
+                } else {
+                    ""
+                }
+            })
+            .collect::<Vec<_>>();
+
+        for line in &render {
+            queue!(self.out, style::Print(line), cursor::MoveToNextLine(1))?;
+        }
+
+        let rendered_lines = render.len();
+        if rendered_lines < max_lines {
+            let empty_lines = max_lines - rendered_lines;
+            for _ in 0..empty_lines {
+                queue!(self.out, style::Print("~"), cursor::MoveToNextLine(1))?;
+            }
+        }
+
+        if !command.is_empty() {
+            queue!(
+                self.out,
+                style::SetAttribute(style::Attribute::Bold),
+                style::Print(command),
+                style::SetAttribute(style::Attribute::Reset),
+                cursor::MoveToNextLine(1)
+            )?;
+        }
+
+        match mode {
+            Mode::INSERT => queue!(self.out, cursor::SetCursorStyle::BlinkingBar)?,
+            _ => queue!(self.out, cursor::SetCursorStyle::DefaultUserShape)?,
+        }
+
+        queue!(self.out, cursor::MoveTo(self.cursor.position.0, self.cursor.position.1))?;
+        self.out.flush()?;
+        Ok(())
+    }
+}

src/util/keymap.rs

@@ -1,8 +1,8 @@
 use color_eyre::Report;
 use crossterm::event::KeyEvent;
-use std::{cell::RefCell, collections::HashMap, fmt, io, rc::Rc};
+use std::{cell::RefCell, collections::HashMap, rc::Rc};
 
-use crate::editor::{ControlCode, Editor, Mode};
+use crate::editor::{Editor, Mode};
 
 type ActionFn = dyn FnMut(&mut Editor) -> Result<(), Report>;
 
@@ -12,18 +12,14 @@ struct KeyNode {
     action: Option<Rc<RefCell<ActionFn>>>,
 }
 
-impl fmt::Debug for KeyNode {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "KeyNode {{ children: {:?} }}", self.children)
-    }
+pub struct Keymap {
+    root: HashMap<Mode, Rc<RefCell<KeyNode>>>,
+    current: Option<Rc<RefCell<KeyNode>>>,
 }
 
 impl KeyNode {
     pub fn new() -> Rc<RefCell<Self>> {
-        Rc::new(RefCell::new(Self {
-            children: HashMap::new(),
-            action: None,
-        }))
+        Rc::new(RefCell::new(Self { children: HashMap::new(), action: None }))
     }
 
     pub fn is_leaf(&self) -> bool {
@@ -43,18 +39,9 @@ impl KeyNode {
     }
 }
 
-#[derive(Debug)]
-pub struct Keymap {
-    root: HashMap<Mode, Rc<RefCell<KeyNode>>>,
-    current: Option<Rc<RefCell<KeyNode>>>,
-}
-
 impl Keymap {
     pub fn new() -> Self {
-        Self {
-            root: HashMap::new(),
-            current: None,
-        }
+        Self { root: HashMap::new(), current: None }
     }
 
     pub fn add_keybind<F>(&mut self, modes: Vec<Mode>, sequence: Vec<KeyEvent>, action: F)

src/util/mod.rs

@@ -1 +1,5 @@
-pub(crate) mod rope;
+pub(crate) mod display;
+pub(crate) mod keymap;
+
+pub(crate) use self::display::Display;
+pub(crate) use self::keymap::Keymap;