Buffer line styling

src/buffer.rs

@@ -21,7 +21,7 @@ use std::io::Write;
 use std::ops::Range;
 use std::sync::Arc;
 
-use crossterm::{cursor, ExecutableCommand};
+use crossterm::{cursor, ExecutableCommand, QueueableCommand};
 use parking_lot::Mutex;
 use ropey::Rope;
 use syntect::easy::ScopeRangeIterator;
@@ -33,7 +33,7 @@ use crate::{Cursor, Direction};
 #[derive(Clone, Debug)]
 pub struct Buffer {
     styles: Arc<Mutex<StyleStore>>,
-    pub text: Rope,
+    text: Rope,
     syntax_set: Arc<SyntaxSet>,
     parser: ParseState,
     style_dirty: bool,
@@ -41,6 +41,12 @@ pub struct Buffer {
     styled: Vec<Vec<(Style, Range<usize>)>>,
 }
 
+impl AsRef<Rope> for Buffer {
+    fn as_ref(&self) -> &Rope {
+        &self.text
+    }
+}
+
 impl Buffer {
     pub fn from_str(styles: Arc<Mutex<StyleStore>>, text: &str) -> Self {
         let syntax_set = SyntaxSet::load_defaults_nonewlines();
@@ -68,7 +74,7 @@ impl Buffer {
         cols: u16,
         rows: u16,
         scroll: Cursor,
-        out: &mut (impl ExecutableCommand + Write),
+        out: &mut impl Write,
     ) -> crossterm::Result<u32> {
         self.parse();
 
@@ -78,8 +84,9 @@ impl Buffer {
         let gutter_width = linenr_width + 1;
         let text_width = cols as usize - gutter_width as usize;
 
-        out.execute(cursor::MoveTo(0, 0))?;
+        out.queue(cursor::MoveTo(0, 0))?;
 
+        let mut line_buf = Vec::<u8>::with_capacity(text_width);
         for (row, line) in (0..rows).zip(self.text.lines_at(scroll.line)) {
             // only the last line is empty and should be skipped
             if line.len_chars() == 0 {
@@ -92,6 +99,7 @@ impl Buffer {
 
             let lhs = scroll.column;
             let width = line.len_chars();
+            line_buf.clear();
             if lhs < width {
                 let window = text_width.min(width - lhs);
                 let rhs = lhs + window;
@@ -101,7 +109,7 @@ impl Buffer {
                     if range.start < range.end {
                         // this range is in view so display
                         let content = line.slice(range.clone());
-                        style.print_styled(out, content)?;
+                        style.print_styled(&mut line_buf, content)?;
                     }
 
                     if range.end >= rhs {
@@ -111,7 +119,8 @@ impl Buffer {
                 }
             }
 
-            out.execute(cursor::MoveToNextLine(1))?;
+            out.write_all(&line_buf)?;
+            out.queue(cursor::MoveToNextLine(1))?;
         }
 
         Ok(gutter_width)
@@ -151,7 +160,7 @@ impl Buffer {
             // parse the line into a sequence of stack operations
             let stack_ops = parser.parse_line(&line_buf, &self.syntax_set).unwrap();
 
-            // execute the operations on the stack
+            // queue the operations on the stack
             let mut line = Vec::new();
             let range_iter = ScopeRangeIterator::new(&stack_ops, &line_buf);
             for (range, op) in range_iter {

src/main.rs

@@ -31,7 +31,7 @@ use crossbeam_channel::Sender;
 use crossterm::{
     cursor,
     event::{Event, KeyCode, KeyEvent},
-    terminal, ExecutableCommand, Result,
+    terminal, Result, QueueableCommand,
 };
 use parking_lot::Mutex;
 use yacexits::{exit, EX_DATAERR, EX_UNAVAILABLE};
@@ -135,8 +135,8 @@ impl State {
     pub fn draw(&mut self, out: &mut impl Write) -> Result<()> {
         // begin update
         let (cols, rows) = terminal::size()?;
-        out.execute(terminal::BeginSynchronizedUpdate)?;
-        out.execute(terminal::Clear(terminal::ClearType::All))?;
+        out.queue(terminal::BeginSynchronizedUpdate)?;
+        out.queue(terminal::Clear(terminal::ClearType::All))?;
         let mut styles = self.styles.lock();
 
         // draw status line
@@ -147,14 +147,14 @@ impl State {
             Mode::Command(CommandState { buf, cursor }) => {
                 let col = *cursor as u16 + 1;
                 let row = rows - 1;
-                out.execute(cursor::MoveTo(0, row))?;
+                out.queue(cursor::MoveTo(0, row))?;
                 write!(out, ":{}", buf)?;
                 set_cursor_pos = Some((col, row));
                 show_status_bar = true;
             }
             Mode::Normal(NormalState { error: Some(error) }) => {
                 let error_style = styles.get_scope("error");
-                out.execute(cursor::MoveTo(0, rows - 1))?;
+                out.queue(cursor::MoveTo(0, rows - 1))?;
                 error_style.print_styled(out, error)?;
                 show_status_bar = true;
             }
@@ -178,11 +178,13 @@ impl State {
             (col, row)
         });
 
-        out.execute(cursor::MoveTo(cursor_pos.0, cursor_pos.1))?;
-        out.execute(self.mode.cursor_style())?;
+        out.queue(cursor::MoveTo(cursor_pos.0, cursor_pos.1))?;
+        out.queue(self.mode.cursor_style())?;
 
         // finish update
-        out.execute(terminal::EndSynchronizedUpdate)?;
+        out.queue(terminal::EndSynchronizedUpdate)?;
+        out.flush()?;
+
         Ok(())
     }
 
@@ -246,7 +248,7 @@ impl State {
                 }
                 KeyCode::Enter => {
                     // TODO add to command history
-                    let result = self.execute_command(&state.buf);
+                    let result = self.queue_command(&state.buf);
                     let error = result.err();
                     self.mode = Mode::Normal(NormalState { error });
                     return;
@@ -325,7 +327,7 @@ impl State {
     }
 
     fn write_buffer(&mut self, file: OsString) -> Result<()> {
-        let out = self.buffer.text.bytes().collect::<Vec<u8>>();
+        let out = self.buffer.as_ref().bytes().collect::<Vec<u8>>();
         let mut handle = OpenOptions::new().write(true).open(file)?;
 
         handle.write_all(out.as_slice())?;
@@ -347,7 +349,7 @@ impl State {
         self.write_buffer(handle).map_err(|err| format!("{}", err))
     }
 
-    fn execute_command(&mut self, command: &str) -> std::result::Result<(), String> {
+    fn queue_command(&mut self, command: &str) -> std::result::Result<(), String> {
         let command_parts = command.split(' ').collect::<Vec<&str>>();
 
         let command = match command_parts.get(0) {
@@ -364,9 +366,16 @@ impl State {
                 self.write_command(command, args)?;
                 self.quit = true;
             }
-            command => {
-                return Err(format!("{}: Unrecognized command.", command));
-            }
+            command => match command.parse::<usize>() {
+                Err(_) => return Err(format!("{}: Unrecognized command.", command)),
+                Ok(line) if line >= self.buffer.as_ref().len_lines() => {
+                    return Err(format!("Line {} is out-of-bounds", line))
+                }
+                Ok(line) => {
+                    self.cursor.line = line;
+                    self.scroll_to_cursor();
+                }
+            },
         }
 
         Ok(())
@@ -374,7 +383,10 @@ impl State {
 
     fn move_cursor(&mut self, direction: Direction) {
         self.buffer.move_cursor(&mut self.cursor, direction, true);
+        self.scroll_to_cursor();
+    }
 
+    fn scroll_to_cursor(&mut self) {
         if self.cursor.column < self.scroll.column + 3 {
             self.scroll.column = self.cursor.column.saturating_sub(3);
         } else if self.cursor.column + 6 >= self.scroll.column + self.size.0 {
@@ -447,9 +459,9 @@ fn main() -> Result<()> {
     let state = State::from_str(file_name, &text)?;
     let mut stdout = stdout();
     terminal::enable_raw_mode()?;
-    stdout.execute(terminal::EnterAlternateScreen)?;
+    stdout.queue(terminal::EnterAlternateScreen)?;
     let result = screen_main(&mut stdout, state);
-    stdout.execute(terminal::LeaveAlternateScreen)?;
+    stdout.queue(terminal::LeaveAlternateScreen)?;
     terminal::disable_raw_mode()?;
     result
 }

src/theme.rs

@@ -17,11 +17,10 @@
  * along with this program. If not, see https://www.gnu.org/licenses/.
  */
 
-use std::io::Write;
 use std::{collections::HashMap, fmt::Display};
 
-use crossterm::{style::Color, ExecutableCommand};
-use once_cell::sync::Lazy;
+use crossterm::style::Color;
+use crossterm::QueueableCommand;
 use toml::{map::Map, Value};
 
 #[derive(Debug, Default)]
@@ -110,22 +109,21 @@ pub struct Style {
 impl Style {
     pub fn print_styled(
         &self,
-        out: &mut (impl ExecutableCommand + Write),
+        out: &mut impl QueueableCommand,
         content: impl Display,
     ) -> crossterm::Result<()> {
-        use crossterm::style::{ResetColor, SetBackgroundColor, SetForegroundColor};
+        use crossterm::style::{Print, ResetColor, SetBackgroundColor, SetForegroundColor};
 
         if let Some(fg) = self.fg {
-            out.execute(SetForegroundColor(fg))?;
+            out.queue(SetForegroundColor(fg))?;
         }
 
         if let Some(bg) = self.bg {
-            out.execute(SetBackgroundColor(bg))?;
+            out.queue(SetBackgroundColor(bg))?;
         }
 
-        write!(out, "{}", content)?;
-
-        out.execute(ResetColor)?;
+        out.queue(Print(content))?;
+        out.queue(ResetColor)?;
 
         Ok(())
     }