1 files changed, 120 insertions, 0 deletions
diff --git a/src/render/mod.rs b/src/render/mod.rs
new file mode 100644
index 0000000..d9fcc95
--- /dev/null
+++ b/src/render/mod.rs
@@ -0,0 +1,120 @@
+mod markdown;
+
+pub use self::markdown::MarkdownRender;
+use crate::repl::ReplyStreamEvent;
+
+use anyhow::Result;
+use crossbeam::channel::Receiver;
+use crossterm::{
+    cursor,
+    event::{self, Event, KeyCode, KeyModifiers},
+    queue, style,
+    terminal::{self, disable_raw_mode, enable_raw_mode},
+};
+use std::{
+    io::{self, Stdout, Write},
+    sync::{
+        atomic::{AtomicBool, Ordering},
+        Arc,
+    },
+    time::{Duration, Instant},
+};
+use unicode_width::UnicodeWidthStr;
+
+pub fn render_stream(rx: Receiver<ReplyStreamEvent>, ctrlc: Arc<AtomicBool>) -> Result<()> {
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    queue!(stdout, event::DisableMouseCapture)?;
+
+    let ret = render_stream_inner(rx, ctrlc, &mut stdout);
+
+    queue!(stdout, event::DisableMouseCapture)?;
+    disable_raw_mode()?;
+
+    ret
+}
+
+pub fn render_stream_inner(
+    rx: Receiver<ReplyStreamEvent>,
+    ctrlc: Arc<AtomicBool>,
+    writer: &mut Stdout,
+) -> Result<()> {
+    let mut last_tick = Instant::now();
+    let tick_rate = Duration::from_millis(200);
+    let mut buffer = String::new();
+    let mut markdown_render = MarkdownRender::new();
+    let terminal_columns = terminal::size()?.0;
+    loop {
+        if ctrlc.load(Ordering::SeqCst) {
+            return Ok(());
+        }
+
+        if let Ok(evt) = rx.try_recv() {
+            recover_cursor(writer, terminal_columns, &buffer)?;
+
+            match evt {
+                ReplyStreamEvent::Text(text) => {
+                    if text.contains('\n') {
+                        let text = format!("{buffer}{text}");
+                        let mut lines: Vec<&str> = text.split('\n').collect();
+                        buffer = lines.pop().unwrap_or_default().to_string();
+                        let output = markdown_render.render(&lines.join("\n"));
+                        queue!(
+                            writer,
+                            style::Print(output),
+                            style::Print("\n"),
+                            style::Print(&buffer),
+                        )?;
+                    } else {
+                        buffer = format!("{buffer}{text}");
+                        let output = markdown_render.render_line_stateless(&buffer);
+                        queue!(writer, style::Print(&output))?;
+                    }
+                    writer.flush()?;
+                }
+                ReplyStreamEvent::Done => {
+                    let output = markdown_render.render_line_stateless(&buffer);
+                    queue!(writer, style::Print(output), style::Print("\n"))?;
+                    writer.flush()?;
+                    break;
+                }
+            }
+            continue;
+        }
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                match key.code {
+                    KeyCode::Char('c') if key.modifiers == KeyModifiers::CONTROL => {
+                        ctrlc.store(true, Ordering::SeqCst);
+                        return Ok(());
+                    }
+                    _ => {}
+                }
+            }
+        }
+
+        if last_tick.elapsed() >= tick_rate {
+            last_tick = Instant::now();
+        }
+    }
+    Ok(())
+}
+
+fn recover_cursor(writer: &mut Stdout, terminal_columns: u16, buffer: &str) -> Result<()> {
+    let buffer_rows = (buffer.width() as u16 + terminal_columns - 1) / terminal_columns;
+    let (_, row) = cursor::position()?;
+    if row + 1 >= buffer_rows {
+        queue!(writer, cursor::MoveTo(0, row + 1 - buffer_rows))?;
+    } else {
+        queue!(
+            writer,
+            terminal::ScrollUp(buffer_rows - 1 - row),
+            cursor::MoveTo(0, 0)
+        )?;
+    }
+    Ok(())
+}