Draft `input_method` support

5 files changed, 183 insertions, 8 deletions

diff --git a/widget/src/combo_box.rs b/widget/src/combo_box.rs
index 500d2bec..d7c7c922 100644
--- a/widget/src/combo_box.rs
+++ b/widget/src/combo_box.rs
@@ -564,6 +564,7 @@ where
                 }
             }
         }
+        shell.update_caret_info(local_shell.caret_info());
 
         // Then finally react to them here
         for message in local_messages {
@@ -742,6 +743,8 @@ where
                 published_message_to_shell = true;
 
                 // Unfocus the input
+                let mut local_messages = Vec::new();
+                let mut local_shell = Shell::new(&mut local_messages);
                 self.text_input.update(
                     &mut tree.children[0],
                     Event::Mouse(mouse::Event::ButtonPressed(
@@ -751,9 +754,10 @@ where
                     mouse::Cursor::Unavailable,
                     renderer,
                     clipboard,
-                    &mut Shell::new(&mut vec![]),
+                    &mut local_shell,
                     viewport,
                 );
+                shell.update_caret_info(local_shell.caret_info());
             }
         });
 
diff --git a/widget/src/lazy/component.rs b/widget/src/lazy/component.rs
index 15b8b62e..b9fbde58 100644
--- a/widget/src/lazy/component.rs
+++ b/widget/src/lazy/component.rs
@@ -355,6 +355,7 @@ where
                 }
             }
         }
+        shell.update_caret_info(local_shell.caret_info());
 
         if !local_messages.is_empty() {
             let mut heads = self.state.take().unwrap().into_heads();
@@ -640,6 +641,7 @@ where
                 }
             }
         }
+        shell.update_caret_info(local_shell.caret_info());
 
         if !local_messages.is_empty() {
             let mut inner =
diff --git a/widget/src/scrollable.rs b/widget/src/scrollable.rs
index 312aee29..7df7a0e5 100644
--- a/widget/src/scrollable.rs
+++ b/widget/src/scrollable.rs
@@ -33,8 +33,9 @@ use crate::core::widget::operation::{self, Operation};
 use crate::core::widget::tree::{self, Tree};
 use crate::core::window;
 use crate::core::{
-    self, Background, Clipboard, Color, Element, Event, Layout, Length,
-    Padding, Pixels, Point, Rectangle, Shell, Size, Theme, Vector, Widget,
+    self, Background, CaretInfo, Clipboard, Color, Element, Event, Layout,
+    Length, Padding, Pixels, Point, Rectangle, Shell, Size, Theme, Vector,
+    Widget,
 };
 use crate::runtime::task::{self, Task};
 use crate::runtime::Action;
@@ -729,6 +730,7 @@ where
                 let translation =
                     state.translation(self.direction, bounds, content_bounds);
 
+                let children_may_have_caret = shell.caret_info().is_none();
                 self.content.as_widget_mut().update(
                     &mut tree.children[0],
                     event.clone(),
@@ -743,6 +745,19 @@ where
                         ..bounds
                     },
                 );
+
+                if children_may_have_caret {
+                    if let Some(caret_info) = shell.caret_info() {
+                        shell.update_caret_info(Some(CaretInfo {
+                            position: Point::new(
+                                caret_info.position.x - translation.x,
+                                caret_info.position.y - translation.y,
+                            ),
+                            input_method_allowed: caret_info
+                                .input_method_allowed,
+                        }));
+                    }
+                }
             };
 
             if matches!(
diff --git a/widget/src/text_editor.rs b/widget/src/text_editor.rs
index f1ec589b..2931e7f6 100644
--- a/widget/src/text_editor.rs
+++ b/widget/src/text_editor.rs
@@ -33,6 +33,7 @@
 //! ```
 use crate::core::alignment;
 use crate::core::clipboard::{self, Clipboard};
+use crate::core::input_method;
 use crate::core::keyboard;
 use crate::core::keyboard::key;
 use crate::core::layout::{self, Layout};
@@ -46,8 +47,8 @@ use crate::core::widget::operation;
 use crate::core::widget::{self, Widget};
 use crate::core::window;
 use crate::core::{
-    Background, Border, Color, Element, Event, Length, Padding, Pixels, Point,
-    Rectangle, Shell, Size, SmolStr, Theme, Vector,
+    Background, Border, CaretInfo, Color, Element, Event, Length, Padding,
+    Pixels, Point, Rectangle, Shell, Size, SmolStr, Theme, Vector,
 };
 
 use std::borrow::Cow;
@@ -322,6 +323,46 @@ where
         self.class = class.into();
         self
     }
+
+    fn caret_rect(
+        &self,
+        tree: &widget::Tree,
+        renderer: &Renderer,
+        layout: Layout<'_>,
+    ) -> Option<Rectangle> {
+        let bounds = layout.bounds();
+
+        let internal = self.content.0.borrow_mut();
+        let state = tree.state.downcast_ref::<State<Highlighter>>();
+
+        let text_bounds = bounds.shrink(self.padding);
+        let translation = text_bounds.position() - Point::ORIGIN;
+
+        if let Some(_) = state.focus.as_ref() {
+            let position = match internal.editor.cursor() {
+                Cursor::Caret(position) => position,
+                Cursor::Selection(ranges) => ranges
+                    .first()
+                    .cloned()
+                    .unwrap_or(Rectangle::default())
+                    .position(),
+            };
+            Some(Rectangle::new(
+                position + translation,
+                Size::new(
+                    1.0,
+                    self.line_height
+                        .to_absolute(
+                            self.text_size
+                                .unwrap_or_else(|| renderer.default_size()),
+                        )
+                        .into(),
+                ),
+            ))
+        } else {
+            None
+        }
+    }
 }
 
 /// The content of a [`TextEditor`].
@@ -605,7 +646,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
-        _renderer: &Renderer,
+        renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, Message>,
         _viewport: &Rectangle,
@@ -701,6 +742,11 @@ where
                     }));
                     shell.capture_event();
                 }
+                Update::Commit(text) => {
+                    shell.publish(on_edit(Action::Edit(Edit::Paste(
+                        Arc::new(text),
+                    ))));
+                }
                 Update::Binding(binding) => {
                     fn apply_binding<
                         H: text::Highlighter,
@@ -825,6 +871,19 @@ where
             }
         };
 
+        shell.update_caret_info(if state.is_focused() {
+            let rect = self
+                .caret_rect(tree, renderer, layout)
+                .unwrap_or(Rectangle::default());
+            let bottom_left = Point::new(rect.x, rect.y + rect.height);
+            Some(CaretInfo {
+                position: bottom_left,
+                input_method_allowed: true,
+            })
+        } else {
+            None
+        });
+
         if is_redraw {
             self.last_status = Some(status);
         } else if self
@@ -1129,6 +1188,7 @@ enum Update<Message> {
     Drag(Point),
     Release,
     Scroll(f32),
+    Commit(String),
     Binding(Binding<Message>),
 }
 
@@ -1191,6 +1251,9 @@ impl<Message> Update<Message> {
                 }
                 _ => None,
             },
+            Event::InputMethod(input_method::Event::Commit(text)) => {
+                Some(Update::Commit(text))
+            }
             Event::Keyboard(keyboard::Event::KeyPressed {
                 key,
                 modifiers,
diff --git a/widget/src/text_input.rs b/widget/src/text_input.rs
index 57ebe46a..f2756b5b 100644
--- a/widget/src/text_input.rs
+++ b/widget/src/text_input.rs
@@ -36,6 +36,7 @@ mod value;
 pub mod cursor;
 
 pub use cursor::Cursor;
+use iced_runtime::core::input_method;
 pub use value::Value;
 
 use editor::Editor;
@@ -56,8 +57,8 @@ use crate::core::widget::operation::{self, Operation};
 use crate::core::widget::tree::{self, Tree};
 use crate::core::window;
 use crate::core::{
-    Background, Border, Color, Element, Event, Layout, Length, Padding, Pixels,
-    Point, Rectangle, Shell, Size, Theme, Vector, Widget,
+    Background, Border, CaretInfo, Color, Element, Event, Layout, Length,
+    Padding, Pixels, Point, Rectangle, Shell, Size, Theme, Vector, Widget,
 };
 use crate::runtime::task::{self, Task};
 use crate::runtime::Action;
@@ -391,6 +392,58 @@ where
         }
     }
 
+    fn caret_rect(
+        &self,
+        tree: &Tree,
+        layout: Layout<'_>,
+        value: Option<&Value>,
+    ) -> Option<Rectangle> {
+        let state = tree.state.downcast_ref::<State<Renderer::Paragraph>>();
+        let value = value.unwrap_or(&self.value);
+
+        let secure_value = self.is_secure.then(|| value.secure());
+        let value = secure_value.as_ref().unwrap_or(value);
+
+        let mut children_layout = layout.children();
+        let text_bounds = children_layout.next().unwrap().bounds();
+
+        if let Some(_) = state
+            .is_focused
+            .as_ref()
+            .filter(|focus| focus.is_window_focused)
+        {
+            let caret_index = match state.cursor.state(value) {
+                cursor::State::Index(position) => position,
+                cursor::State::Selection { start, end } => {
+                    let left = start.min(end);
+                    left
+                }
+            };
+            let text = state.value.raw();
+            let (caret_x, offset) = measure_cursor_and_scroll_offset(
+                text,
+                text_bounds,
+                caret_index,
+            );
+
+            let alignment_offset = alignment_offset(
+                text_bounds.width,
+                text.min_width(),
+                self.alignment,
+            );
+
+            let x = (text_bounds.x + caret_x).floor();
+            Some(Rectangle {
+                x: (alignment_offset - offset) + x,
+                y: text_bounds.y,
+                width: 1.0,
+                height: text_bounds.height,
+            })
+        } else {
+            None
+        }
+    }
+
     /// Draws the [`TextInput`] with the given [`Renderer`], overriding its
     /// [`Value`] if provided.
     ///
@@ -1197,6 +1250,31 @@ where
 
                 state.keyboard_modifiers = *modifiers;
             }
+            Event::InputMethod(input_method::Event::Commit(string)) => {
+                let state = state::<Renderer>(tree);
+
+                if let Some(focus) = &mut state.is_focused {
+                    let Some(on_input) = &self.on_input else {
+                        return;
+                    };
+
+                    state.is_pasting = None;
+
+                    let mut editor =
+                        Editor::new(&mut self.value, &mut state.cursor);
+
+                    editor.paste(Value::new(&string));
+
+                    let message = (on_input)(editor.contents());
+                    shell.publish(message);
+
+                    focus.updated_at = Instant::now();
+
+                    update_cache(state, &self.value);
+
+                    shell.capture_event();
+                }
+            }
             Event::Window(window::Event::Unfocused) => {
                 let state = state::<Renderer>(tree);
 
@@ -1256,6 +1334,19 @@ where
             Status::Active
         };
 
+        shell.update_caret_info(if state.is_focused() {
+            let rect = self
+                .caret_rect(tree, layout, Some(&self.value))
+                .unwrap_or(Rectangle::with_size(Size::<f32>::default()));
+            let bottom_left = Point::new(rect.x, rect.y + rect.height);
+            Some(CaretInfo {
+                position: bottom_left,
+                input_method_allowed: true,
+            })
+        } else {
+            None
+        });
+
         if let Event::Window(window::Event::RedrawRequested(_now)) = event {
             self.last_status = Some(status);
         } else if self