From 5b4e544911f3613186b03daa095a16f0573af8ea Mon Sep 17 00:00:00 2001
From: Matt Hunzinger <matthunz2@gmail.com>
Date: Fri, 21 Jun 2024 14:23:08 -0400
Subject: [PATCH] Send basic tree updates on dom change

---
 packages/dioxus-blitz/src/window.rs | 65 ++++++++++++++++++++++++++++-
 packages/dom/src/document.rs        | 11 ++++-
 2 files changed, 73 insertions(+), 3 deletions(-)

diff --git a/packages/dioxus-blitz/src/window.rs b/packages/dioxus-blitz/src/window.rs
index e90573c6..b78fc578 100644
--- a/packages/dioxus-blitz/src/window.rs
+++ b/packages/dioxus-blitz/src/window.rs
@@ -1,12 +1,13 @@
 use crate::waker::UserEvent;
 use blitz::{RenderState, Renderer, Viewport};
-use blitz_dom::DocumentLike;
+use blitz_dom::{Document, DocumentLike, Node};
 use winit::keyboard::PhysicalKey;
 
 #[allow(unused)]
 use wgpu::rwh::HasWindowHandle;
 
 use muda::{AboutMetadata, Menu, MenuId, MenuItem, PredefinedMenuItem, Submenu};
+use std::mem;
 use std::sync::Arc;
 use std::task::Waker;
 use vello::Scene;
@@ -23,10 +24,40 @@ struct State {
     #[cfg(feature = "accesskit")]
     node_ids: std::collections::HashMap<accesskit::NodeId, usize>,
 
+    #[cfg(feature = "accesskit")]
+    next_id: u64,
+
     /// Main menu bar of this view's window.
     _menu: Menu,
 }
 
+impl State {
+    fn build_node(&mut self, node_id: usize, node: &Node) -> (accesskit::NodeId, accesskit::Node) {
+        let mut node_builder = accesskit::NodeBuilder::default();
+        if let Some(element_data) = node.element_data() {
+            let name = element_data.name.local.to_string();
+            let role = match &*name {
+                "button" => accesskit::Role::Button,
+                "div" | "section" => accesskit::Role::Group,
+                "p" => accesskit::Role::Paragraph,
+                _ => accesskit::Role::Unknown,
+            };
+
+            node_builder.set_role(role);
+            node_builder.set_name(name);
+        } else if node.is_text_node() {
+            node_builder.set_role(accesskit::Role::StaticText);
+            node_builder.set_name(node.text_content());
+        }
+
+        let id = accesskit::NodeId(self.next_id);
+        self.next_id += 1;
+
+        self.node_ids.insert(id, node_id);
+        (id, node_builder.build())
+    }
+}
+
 pub(crate) struct View<'s, Doc: DocumentLike> {
     pub(crate) renderer: Renderer<'s, Window, Doc>,
     pub(crate) scene: Scene,
@@ -57,7 +88,35 @@ impl<'a, Doc: DocumentLike> View<'a, Doc> {
             None => false,
             Some(waker) => {
                 let cx = std::task::Context::from_waker(waker);
-                self.renderer.poll(cx)
+                if self.renderer.poll(cx) {
+                    let Some(ref mut state) = self.state else {
+                        return true;
+                    };
+
+                    let changed = mem::take(&mut self.renderer.dom.as_mut().changed);
+                    if !changed.is_empty() {
+                        let doc = self.renderer.dom.as_ref();
+
+                        let nodes = changed
+                            .iter()
+                            .map(|id| {
+                                let node = doc.get_node(*id).unwrap();
+                                state.build_node(*id, node)
+                            })
+                            .collect();
+
+                        let tree_update = accesskit::TreeUpdate {
+                            nodes,
+                            tree: None,
+                            focus: accesskit::NodeId(1),
+                        };
+                        state.adapter.update_if_active(|| tree_update);
+                    }
+
+                    true
+                } else {
+                    false
+                }
             }
         }
     }
@@ -366,6 +425,8 @@ impl<'a, Doc: DocumentLike> View<'a, Doc> {
                 adapter: accesskit_winit::Adapter::with_event_loop_proxy(&window, proxy.clone()),
                 #[cfg(feature = "accesskit")]
                 node_ids: Default::default(),
+                #[cfg(feature = "accesskit")]
+                next_id: 1,
                 _menu: menu,
             });
 
diff --git a/packages/dom/src/document.rs b/packages/dom/src/document.rs
index 7fe878a4..5182c8ea 100644
--- a/packages/dom/src/document.rs
+++ b/packages/dom/src/document.rs
@@ -5,7 +5,7 @@ use crate::{Node, NodeData, TextNodeData};
 use selectors::{matching::QuirksMode, Element};
 use slab::Slab;
 use std::any::Any;
-use std::collections::{HashMap, VecDeque};
+use std::collections::{HashMap, HashSet, VecDeque};
 use style::invalidation::element::restyle_hints::RestyleHint;
 use style::selector_parser::ServoElementSnapshot;
 use style::servo::media_queries::FontMetricsProvider;
@@ -92,6 +92,8 @@ pub struct Document {
     pub(crate) layout_ctx: parley::LayoutContext<TextBrush>,
 
     pub(crate) hover_node_id: Option<usize>,
+
+    pub changed: HashSet<usize>,
 }
 
 impl Document {
@@ -122,6 +124,7 @@ impl Document {
             layout_ctx: parley::LayoutContext::new(),
 
             hover_node_id: None,
+            changed: HashSet::new(),
         };
 
         // Initialise document with root Document node
@@ -184,6 +187,9 @@ impl Document {
         //     id as usize,
         // );
 
+        // Mark the new node as changed.
+        self.changed.insert(id);
+
         id
     }
 
@@ -227,6 +233,9 @@ impl Document {
         let parent_id = node.parent.unwrap_or_default();
         let parent = &mut self.nodes[parent_id];
 
+        // Mark the node's parent as changed.
+        self.changed.insert(parent_id);
+
         let mut children = std::mem::take(&mut parent.children);
         children.splice(
             node_child_idx..node_child_idx,