From 4855b8f3dea4f765d7684899955fe1756a22fcd6 Mon Sep 17 00:00:00 2001
From: Antonio Scandurra <me@as-cii.com>
Date: Tue, 10 Oct 2023 20:02:23 +0200
Subject: [PATCH] WIP

---
 crates/gpui3/src/elements.rs           |   2 +
 crates/gpui3/src/elements/pressable.rs | 229 ++++++++++++++++++-------
 2 files changed, 169 insertions(+), 62 deletions(-)

diff --git a/crates/gpui3/src/elements.rs b/crates/gpui3/src/elements.rs
index 5c8381ad77d9ee1467abbe5c312f860e7daef77f..b2653b22a3231aae904dbc39ea405cb0296e3ccd 100644
--- a/crates/gpui3/src/elements.rs
+++ b/crates/gpui3/src/elements.rs
@@ -2,6 +2,7 @@ mod div;
 mod hoverable;
 mod identified;
 mod img;
+mod pressable;
 mod stateless;
 mod svg;
 mod text;
@@ -10,6 +11,7 @@ pub use div::*;
 pub use hoverable::*;
 pub use identified::*;
 pub use img::*;
+pub use pressable::*;
 pub use stateless::*;
 pub use svg::*;
 pub use text::*;
diff --git a/crates/gpui3/src/elements/pressable.rs b/crates/gpui3/src/elements/pressable.rs
index 6e9b031edae0905541d14bcd6b232589936bb3cd..9390785ba853092ec9f573142ea64ba6f83af49a 100644
--- a/crates/gpui3/src/elements/pressable.rs
+++ b/crates/gpui3/src/elements/pressable.rs
@@ -1,106 +1,211 @@
 use crate::{
-    element::{AnyElement, Element, IntoElement, Layout, ParentElement},
-    interactive::{InteractionHandlers, Interactive},
-    style::{Style, StyleHelpers, Styleable},
-    ViewContext,
+    AnyElement, Bounds, DispatchPhase, Element, Identified, Interactive, MouseDownEvent,
+    MouseEventListeners, MouseMoveEvent, MouseUpEvent, ParentElement, Pixels, Styled, ViewContext,
 };
 use anyhow::Result;
-use gpui::{geometry::vector::Vector2F, platform::MouseButtonEvent, LayoutId};
 use refineable::{CascadeSlot, Refineable, RefinementCascade};
 use smallvec::SmallVec;
-use std::{cell::Cell, rc::Rc};
+use std::sync::{
+    atomic::{AtomicBool, Ordering::SeqCst},
+    Arc,
+};
 
-pub struct Pressable<E: Styleable> {
-    pressed: Rc<Cell<bool>>,
-    pressed_style: <E::Style as Refineable>::Refinement,
+pub struct Pressable<E: Styled> {
+    pressed: Arc<AtomicBool>,
     cascade_slot: CascadeSlot,
+    pressed_style: <E::Style as Refineable>::Refinement,
     child: E,
 }
 
-pub fn pressable<E: Styleable>(mut child: E) -> Pressable<E> {
-    Pressable {
-        pressed: Rc::new(Cell::new(false)),
-        pressed_style: Default::default(),
-        cascade_slot: child.style_cascade().reserve(),
-        child,
+impl<E: Identified + Styled> Pressable<E> {
+    pub fn new(mut child: E) -> Self {
+        Self {
+            pressed: Arc::new(AtomicBool::new(false)),
+            cascade_slot: child.style_cascade().reserve(),
+            pressed_style: Default::default(),
+            child,
+        }
     }
 }
 
-impl<E: Styleable> Styleable for Pressable<E> {
+impl<E> Styled for Pressable<E>
+where
+    E: Styled,
+{
     type Style = E::Style;
 
-    fn declared_style(&mut self) -> &mut <Self::Style as Refineable>::Refinement {
+    fn style_cascade(&mut self) -> &mut RefinementCascade<E::Style> {
+        self.child.style_cascade()
+    }
+
+    fn declared_style(&mut self) -> &mut <Self::Style as refineable::Refineable>::Refinement {
         &mut self.pressed_style
     }
+}
 
-    fn style_cascade(&mut self) -> &mut RefinementCascade<E::Style> {
-        self.child.style_cascade()
+impl<S: 'static + Send + Sync, E: Interactive<S> + Styled> Interactive<S> for Pressable<E> {
+    fn listeners(&mut self) -> &mut MouseEventListeners<S> {
+        self.child.listeners()
     }
 }
 
-impl<V: 'static, E: Element<V> + Styleable> Element<V> for Pressable<E> {
-    type PaintState = E::PaintState;
+impl<E: Element + Identified + Styled> Element for Pressable<E> {
+    type State = E::State;
+    type FrameState = E::FrameState;
 
     fn layout(
         &mut self,
-        view: &mut V,
-        cx: &mut ViewContext<V>,
-    ) -> Result<(LayoutId, Self::PaintState)>
-    where
-        Self: Sized,
-    {
-        self.child.layout(view, cx)
+        state: &mut Self::State,
+        cx: &mut ViewContext<Self::State>,
+    ) -> Result<(crate::LayoutId, Self::FrameState)> {
+        Ok(self.child.layout(state, cx)?)
     }
 
     fn paint(
         &mut self,
-        view: &mut V,
-        parent_origin: Vector2F,
-        layout: &Layout,
-        paint_state: &mut Self::PaintState,
-        cx: &mut ViewContext<V>,
-    ) where
-        Self: Sized,
-    {
+        bounds: Bounds<Pixels>,
+        state: &mut Self::State,
+        frame_state: &mut Self::FrameState,
+        cx: &mut ViewContext<Self::State>,
+    ) -> Result<()> {
+        let pressed = bounds.contains_point(cx.mouse_position());
         let slot = self.cascade_slot;
-        let style = self.pressed.get().then_some(self.pressed_style.clone());
+        let style = pressed.then_some(self.pressed_style.clone());
         self.style_cascade().set(slot, style);
+        self.pressed.store(pressed, SeqCst);
 
-        let pressed = self.pressed.clone();
-        let bounds = layout.bounds + parent_origin;
-        cx.on_event(layout.order, move |_view, event: &MouseButtonEvent, cx| {
-            if event.is_down {
-                if bounds.contains_point(event.position) {
-                    pressed.set(true);
-                    cx.repaint();
+        let hovered = self.pressed.clone();
+        cx.on_mouse_event(move |event: &MouseDownEvent, phase, cx| {
+            if phase == DispatchPhase::Capture {
+                if bounds.contains_point(event.position) != hovered.load(SeqCst) {
+                    cx.notify();
+                }
+            }
+        });
+        cx.on_mouse_event(move |event: &MouseUpEvent, phase, cx| {
+            if phase == DispatchPhase::Capture {
+                if bounds.contains_point(event.position) != hovered.load(SeqCst) {
+                    cx.notify();
                 }
-            } else if pressed.get() {
-                pressed.set(false);
-                cx.repaint();
             }
         });
 
-        self.child
-            .paint(view, parent_origin, layout, paint_state, cx);
+        self.child.paint(bounds, state, frame_state, cx)?;
+        Ok(())
     }
 }
 
-impl<V: 'static, E: Interactive<V> + Styleable> Interactive<V> for Pressable<E> {
-    fn interaction_handlers(&mut self) -> &mut InteractionHandlers<V> {
-        self.child.interaction_handlers()
-    }
-}
+impl<E: ParentElement + Styled> ParentElement for Pressable<E> {
+    type State = E::State;
 
-impl<V: 'static, E: ParentElement<V> + Styleable> ParentElement<V> for Pressable<E> {
-    fn children_mut(&mut self) -> &mut SmallVec<[AnyElement<V>; 2]> {
+    fn children_mut(&mut self) -> &mut SmallVec<[AnyElement<Self::State>; 2]> {
         self.child.children_mut()
     }
 }
 
-impl<V: 'static, E: Element<V> + Styleable> IntoElement<V> for Pressable<E> {
-    type Element = Self;
+// use crate::{
+//     element::{AnyElement, Element, IntoElement, Layout, ParentElement},
+//     interactive::{InteractionHandlers, Interactive},
+//     style::{Style, StyleHelpers, Styleable},
+//     ViewContext,
+// };
+// use anyhow::Result;
+// use gpui::{geometry::vector::Vector2F, platform::MouseButtonEvent, LayoutId};
+// use refineable::{CascadeSlot, Refineable, RefinementCascade};
+// use smallvec::SmallVec;
+// use std::{cell::Cell, rc::Rc};
 
-    fn into_element(self) -> Self::Element {
-        self
-    }
-}
+// pub struct Pressable<E: Styleable> {
+//     pressed: Rc<Cell<bool>>,
+//     pressed_style: <E::Style as Refineable>::Refinement,
+//     cascade_slot: CascadeSlot,
+//     child: E,
+// }
+
+// pub fn pressable<E: Styleable>(mut child: E) -> Pressable<E> {
+//     Pressable {
+//         pressed: Rc::new(Cell::new(false)),
+//         pressed_style: Default::default(),
+//         cascade_slot: child.style_cascade().reserve(),
+//         child,
+//     }
+// }
+
+// impl<E: Styleable> Styleable for Pressable<E> {
+//     type Style = E::Style;
+
+//     fn declared_style(&mut self) -> &mut <Self::Style as Refineable>::Refinement {
+//         &mut self.pressed_style
+//     }
+
+//     fn style_cascade(&mut self) -> &mut RefinementCascade<E::Style> {
+//         self.child.style_cascade()
+//     }
+// }
+
+// impl<V: 'static, E: Element<V> + Styleable> Element<V> for Pressable<E> {
+//     type PaintState = E::PaintState;
+
+//     fn layout(
+//         &mut self,
+//         view: &mut V,
+//         cx: &mut ViewContext<V>,
+//     ) -> Result<(LayoutId, Self::PaintState)>
+//     where
+//         Self: Sized,
+//     {
+//         self.child.layout(view, cx)
+//     }
+
+//     fn paint(
+//         &mut self,
+//         view: &mut V,
+//         parent_origin: Vector2F,
+//         layout: &Layout,
+//         paint_state: &mut Self::PaintState,
+//         cx: &mut ViewContext<V>,
+//     ) where
+//         Self: Sized,
+//     {
+//         let slot = self.cascade_slot;
+//         let style = self.pressed.get().then_some(self.pressed_style.clone());
+//         self.style_cascade().set(slot, style);
+
+//         let pressed = self.pressed.clone();
+//         let bounds = layout.bounds + parent_origin;
+//         cx.on_event(layout.order, move |_view, event: &MouseButtonEvent, cx| {
+//             if event.is_down {
+//                 if bounds.contains_point(event.position) {
+//                     pressed.set(true);
+//                     cx.repaint();
+//                 }
+//             } else if pressed.get() {
+//                 pressed.set(false);
+//                 cx.repaint();
+//             }
+//         });
+
+//         self.child
+//             .paint(view, parent_origin, layout, paint_state, cx);
+//     }
+// }
+
+// impl<V: 'static, E: Interactive<V> + Styleable> Interactive<V> for Pressable<E> {
+//     fn interaction_handlers(&mut self) -> &mut InteractionHandlers<V> {
+//         self.child.interaction_handlers()
+//     }
+// }
+
+// impl<V: 'static, E: ParentElement<V> + Styleable> ParentElement<V> for Pressable<E> {
+//     fn children_mut(&mut self) -> &mut SmallVec<[AnyElement<V>; 2]> {
+//         self.child.children_mut()
+//     }
+// }
+
+// impl<V: 'static, E: Element<V> + Styleable> IntoElement<V> for Pressable<E> {
+//     type Element = Self;
+
+//     fn into_element(self) -> Self::Element {
+//         self
+//     }
+// }