Add cursor kind to separate hidden cursor from pos

Now IME cursor position should be correct since we can still set cursor
position without drawing the cursor.

7 files changed, 58 insertions, 34 deletions

diff --git a/helix-term/src/compositor.rs b/helix-term/src/compositor.rs
index 99f9bb0e..6b39bb62 100644
--- a/helix-term/src/compositor.rs
+++ b/helix-term/src/compositor.rs
@@ -4,7 +4,7 @@
 
 use crossterm::event::Event;
 use helix_core::Position;
-use tui::{buffer::Buffer as Surface, layout::Rect};
+use tui::{buffer::Buffer as Surface, layout::Rect, terminal::CursorKind};
 
 pub type Callback = Box<dyn FnOnce(&mut Compositor)>;
 
@@ -47,8 +47,9 @@ pub trait Component: Any + AnyComponent {
     /// Render the component onto the provided surface.
     fn render(&self, area: Rect, frame: &mut Surface, ctx: &mut Context);
 
-    fn cursor_position(&self, area: Rect, ctx: &Editor) -> Option<Position> {
-        None
+    /// Get cursor position and cursor kind.
+    fn cursor(&self, area: Rect, ctx: &Editor) -> (Option<Position>, CursorKind) {
+        (None, CursorKind::Hidden)
     }
 
     /// May be used by the parent component to compute the child area.
@@ -137,20 +138,19 @@ impl Compositor {
             layer.render(area, surface, cx)
         }
 
-        let pos = self
-            .cursor_position(area, cx.editor)
-            .map(|pos| (pos.col as u16, pos.row as u16));
+        let (pos, kind) = self.cursor(area, cx.editor);
+        let pos = pos.map(|pos| (pos.col as u16, pos.row as u16));
 
-        self.terminal.draw(pos);
+        self.terminal.draw(pos, kind);
     }
 
-    pub fn cursor_position(&self, area: Rect, editor: &Editor) -> Option<Position> {
+    pub fn cursor(&self, area: Rect, editor: &Editor) -> (Option<Position>, CursorKind) {
         for layer in self.layers.iter().rev() {
-            if let Some(pos) = layer.cursor_position(area, editor) {
-                return Some(pos);
+            if let (Some(pos), kind) = layer.cursor(area, editor) {
+                return (Some(pos), kind);
             }
         }
-        None
+        (None, CursorKind::Hidden)
     }
 
     pub fn find(&mut self, type_name: &str) -> Option<&mut dyn Component> {
diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
index 5913df29..95587b4c 100644
--- a/helix-term/src/ui/editor.rs
+++ b/helix-term/src/ui/editor.rs
@@ -26,6 +26,7 @@ use tui::{
     buffer::Buffer as Surface,
     layout::Rect,
     style::{Color, Modifier, Style},
+    terminal::CursorKind,
 };
 
 pub struct EditorView {
@@ -739,15 +740,12 @@ impl Component for EditorView {
         }
     }
 
-    fn cursor_position(&self, area: Rect, editor: &Editor) -> Option<Position> {
+    fn cursor(&self, area: Rect, editor: &Editor) -> (Option<Position>, CursorKind) {
         // match view.doc.mode() {
         //     Mode::Insert => write!(stdout, "\x1B[6 q"),
         //     mode => write!(stdout, "\x1B[2 q"),
         // };
-        // return editor.cursor_position()
-
-        // It's easier to just not render the cursor and use selection rendering instead.
-        None
+        editor.cursor()
     }
 }
 
diff --git a/helix-term/src/ui/picker.rs b/helix-term/src/ui/picker.rs
index 20d51d5d..0aec9894 100644
--- a/helix-term/src/ui/picker.rs
+++ b/helix-term/src/ui/picker.rs
@@ -16,6 +16,7 @@ use crate::ui::{Prompt, PromptEvent};
 use helix_core::Position;
 use helix_view::editor::Action;
 use helix_view::Editor;
+use tui::terminal::CursorKind;
 
 pub struct Picker<T> {
     options: Vec<T>,
@@ -304,7 +305,7 @@ impl<T: 'static> Component for Picker<T> {
         }
     }
 
-    fn cursor_position(&self, area: Rect, editor: &Editor) -> Option<Position> {
+    fn cursor(&self, area: Rect, editor: &Editor) -> (Option<Position>, CursorKind) {
         // TODO: this is mostly duplicate code
         let area = inner_rect(area);
         let block = Block::default().borders(Borders::ALL);
@@ -314,6 +315,6 @@ impl<T: 'static> Component for Picker<T> {
         // prompt area
         let area = Rect::new(inner.x + 1, inner.y, inner.width - 1, 1);
 
-        self.prompt.cursor_position(area, editor)
+        self.prompt.cursor(area, editor)
     }
 }
diff --git a/helix-term/src/ui/popup.rs b/helix-term/src/ui/popup.rs
index ca349403..8488d1c6 100644
--- a/helix-term/src/ui/popup.rs
+++ b/helix-term/src/ui/popup.rs
@@ -116,7 +116,7 @@ impl<T: Component> Component for Popup<T> {
 
         let position = self
             .position
-            .or_else(|| cx.editor.cursor_position())
+            .or_else(|| cx.editor.cursor().0)
             .unwrap_or_default();
 
         let (width, height) = self.size;
diff --git a/helix-term/src/ui/prompt.rs b/helix-term/src/ui/prompt.rs
index c388c315..7b8af820 100644
--- a/helix-term/src/ui/prompt.rs
+++ b/helix-term/src/ui/prompt.rs
@@ -4,6 +4,7 @@ use crossterm::event::{Event, KeyCode, KeyEvent, KeyModifiers};
 use helix_core::Position;
 use helix_view::{Editor, Theme};
 use std::{borrow::Cow, ops::RangeFrom};
+use tui::terminal::CursorKind;
 
 pub type Completion = (RangeFrom<usize>, Cow<'static, str>);
 
@@ -342,11 +343,14 @@ impl Component for Prompt {
         self.render_prompt(area, surface, cx)
     }
 
-    fn cursor_position(&self, area: Rect, editor: &Editor) -> Option<Position> {
+    fn cursor(&self, area: Rect, editor: &Editor) -> (Option<Position>, CursorKind) {
         let line = area.height as usize - 1;
-        Some(Position::new(
-            area.y as usize + line,
-            area.x as usize + self.prompt.len() + self.cursor,
-        ))
+        (
+            Some(Position::new(
+                area.y as usize + line,
+                area.x as usize + self.prompt.len() + self.cursor,
+            )),
+            CursorKind::Block,
+        )
     }
 }
diff --git a/helix-tui/src/terminal.rs b/helix-tui/src/terminal.rs
index ad1e8da3..e8f8f359 100644
--- a/helix-tui/src/terminal.rs
+++ b/helix-tui/src/terminal.rs
@@ -8,6 +8,19 @@ enum ResizeBehavior {
     Auto,
 }
 
+#[derive(Debug)]
+/// UNSTABLE
+pub enum CursorKind {
+    /// █
+    Block,
+    /// |
+    // Bar,
+    /// _
+    // Underline,
+    /// Hidden cursor, can set cursor position with this to let IME have correct cursor position.
+    Hidden,
+}
+
 #[derive(Debug, Clone, PartialEq)]
 /// UNSTABLE
 pub struct Viewport {
@@ -147,7 +160,11 @@ where
 
     /// Synchronizes terminal size, calls the rendering closure, flushes the current internal state
     /// and prepares for the next draw call.
-    pub fn draw(&mut self, cursor_position: Option<(u16, u16)>) -> io::Result<()> {
+    pub fn draw(
+        &mut self,
+        cursor_position: Option<(u16, u16)>,
+        cursor_kind: CursorKind,
+    ) -> io::Result<()> {
         // // Autoresize - otherwise we get glitches if shrinking or potential desync between widgets
         // // and the terminal (if growing), which may OOB.
         // self.autoresize()?;
@@ -162,12 +179,13 @@ where
         // Draw to stdout
         self.flush()?;
 
-        match cursor_position {
-            None => self.hide_cursor()?,
-            Some((x, y)) => {
-                self.show_cursor()?;
-                self.set_cursor(x, y)?;
-            }
+        if let Some((x, y)) = cursor_position {
+            self.set_cursor(x, y)?;
+        }
+
+        match cursor_kind {
+            CursorKind::Block => self.show_cursor()?,
+            CursorKind::Hidden => self.hide_cursor()?,
         }
 
         // Swap buffers
diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index 2fd01817..24f43c0e 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -1,5 +1,6 @@
 use crate::{theme::Theme, tree::Tree, Document, DocumentId, RegisterSelection, View, ViewId};
 use tui::layout::Rect;
+use tui::terminal::CursorKind;
 
 use std::path::PathBuf;
 
@@ -9,6 +10,7 @@ use anyhow::Error;
 
 pub use helix_core::diagnostic::Severity;
 pub use helix_core::register::Registers;
+use helix_core::Position;
 
 #[derive(Debug)]
 pub struct Editor {
@@ -276,7 +278,7 @@ impl Editor {
     //     let doc = &mut editor.documents[id];
     // }
 
-    pub fn cursor_position(&self) -> Option<helix_core::Position> {
+    pub fn cursor(&self) -> (Option<Position>, CursorKind) {
         const OFFSET: u16 = 7; // 1 diagnostic + 5 linenr + 1 gutter
         let view = self.view();
         let doc = &self.documents[view.doc];
@@ -284,8 +286,9 @@ impl Editor {
         if let Some(mut pos) = view.screen_coords_at_pos(doc, doc.text().slice(..), cursor) {
             pos.col += view.area.x as usize + OFFSET as usize;
             pos.row += view.area.y as usize;
-            return Some(pos);
+            (Some(pos), CursorKind::Hidden)
+        } else {
+            (None, CursorKind::Hidden)
         }
-        None
     }
 }