refactor: optimize clear screen

src/main.rs

@@ -1,9 +1,9 @@
 mod cli;
 mod client;
 mod config;
-mod editor;
 mod render;
 mod repl;
+mod term;
 mod utils;
 
 use std::sync::Arc;

src/repl.rs

@@ -1,7 +1,7 @@
 use crate::client::ChatGptClient;
 use crate::config::{Config, Role};
-use crate::editor;
 use crate::render::{self, MarkdownRender};
+use crate::term;
 use crate::utils::{copy, dump};
 use anyhow::{anyhow, Result};
 use crossbeam::channel::{unbounded, Sender};
@@ -115,7 +115,7 @@ impl Repl {
                     dump_repl_help();
                 }
                 ".clear" => match args {
-                    Some("screen") => self.editor.clear_scrollback()?,
+                    Some("screen") => term::clear_screen(0)?,
                     Some("history") => {
                         let history = Box::new(self.editor.history_mut());
                         history
@@ -139,7 +139,7 @@ impl Repl {
                         "// Entering editor mode (Ctrl+D to finish, Ctrl+C to cancel)",
                         1,
                     );
-                    let content = editor::edit()?;
+                    let content = term::edit()?;
                     dump("", 1);
                     handler.handle(ReplCmd::Submit(content))?;
                 }
@@ -189,6 +189,11 @@ impl Repl {
                 ReedlineEvent::MenuNext,
             ]),
         );
+        keybindings.add_binding(
+            KeyModifiers::CONTROL,
+            KeyCode::Char('l'),
+            ReedlineEvent::ExecuteHostCommand(".clear screen".into()),
+        );
         keybindings
     }
 

src/editor.rs → src/term.rs

@@ -6,7 +6,7 @@ use crossterm::{
     cursor,
     event::{self, Event, KeyCode, KeyModifiers},
     queue, style,
-    terminal::{self, disable_raw_mode, enable_raw_mode},
+    terminal::{self, disable_raw_mode, enable_raw_mode, ClearType},
 };
 
 use crate::utils::paste;
@@ -108,3 +108,29 @@ impl<'a, T: Write> Session<'a, T> {
         Ok(())
     }
 }
+
+pub fn clear_screen(keep_lines: u16) -> Result<()> {
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+
+    let ret = clear_screen_inner(&mut stdout, keep_lines);
+
+    // restore terminal
+    disable_raw_mode()?;
+
+    ret
+}
+
+fn clear_screen_inner(writer: &mut Stdout, keep_lines: u16) -> Result<()> {
+    let (_, h) = terminal::size()?;
+    queue!(
+        writer,
+        style::Print("\n".repeat((h - 2).into())),
+        terminal::ScrollUp(2),
+        cursor::MoveTo(0, 0),
+        terminal::Clear(ClearType::FromCursorDown),
+        terminal::ScrollUp(keep_lines),
+    )?;
+    writer.flush()?;
+    Ok(())
+}