Move everything unrelated to the frame tree out of Page and into Document or Window. Reduce the API surface of Page to a bare minimum to allow for easier future removal.

components/script/dom/window.rs

@@ -8,50 +8,59 @@ use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::WindowBinding;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
-use dom::bindings::codegen::InheritTypes::EventTargetCast;
+use dom::bindings::codegen::InheritTypes::{NodeCast, EventTargetCast};
 use dom::bindings::global::global_object_for_js_object;
 use dom::bindings::error::{report_pending_exception, Fallible};
 use dom::bindings::error::Error::InvalidCharacter;
 use dom::bindings::global::GlobalRef;
-use dom::bindings::js::{MutNullableJS, JSRef, Temporary};
-use dom::bindings::utils::Reflectable;
+use dom::bindings::js::{MutNullableJS, JSRef, Temporary, OptionalRootable, RootedReference};
+use dom::bindings::utils::{GlobalStaticData, Reflectable, WindowProxyHandler};
 use dom::browsercontext::BrowserContext;
 use dom::console::Console;
-use dom::document::Document;
+use dom::document::{Document, DocumentHelpers};
 use dom::element::Element;
 use dom::eventtarget::{EventTarget, EventTargetHelpers, EventTargetTypeId};
 use dom::location::Location;
 use dom::navigator::Navigator;
-use dom::node::window_from_node;
+use dom::node::{window_from_node, Node, TrustedNodeAddress, NodeHelpers};
 use dom::performance::Performance;
 use dom::screen::Screen;
 use dom::storage::Storage;
-use layout_interface::{ReflowGoal, ReflowQueryType};
+use layout_interface::{ReflowGoal, ReflowQueryType, LayoutRPC, LayoutChan, Reflow, Msg};
+use layout_interface::{ContentBoxResponse, ContentBoxesResponse};
 use page::Page;
 use script_task::{TimerSource, ScriptChan};
 use script_task::ScriptMsg;
 use script_traits::ScriptControlChan;
 use timers::{IsInterval, TimerId, TimerManager, TimerCallback};
 
+use devtools_traits::DevtoolsControlChan;
 use msg::compositor_msg::ScriptListener;
-use msg::constellation_msg::LoadData;
+use msg::constellation_msg::{LoadData, PipelineId, SubpageId, ConstellationChan, WindowSizeData};
 use net::image_cache_task::ImageCacheTask;
+use net::resource_task::ResourceTask;
 use net::storage_task::StorageTask;
+use util::geometry::{self, Au, MAX_RECT};
 use util::str::{DOMString,HTML_SPACE_CHARACTERS};
 
+use geom::{Point2D, Rect, Size2D};
 use js::jsapi::JS_EvaluateUCScript;
 use js::jsapi::JSContext;
 use js::jsapi::{JS_GC, JS_GetRuntime};
 use js::jsval::{JSVal, UndefinedValue};
-use js::rust::with_compartment;
+use js::rust::{Cx, with_compartment};
 use url::{Url, UrlParser};
 
 use libc;
 use rustc_serialize::base64::{FromBase64, ToBase64, STANDARD};
-use std::cell::{Ref, RefMut};
+use std::cell::{Cell, Ref, RefMut};
 use std::default::Default;
 use std::ffi::CString;
+use std::mem::replace;
+use std::num::Float;
 use std::rc::Rc;
+use std::sync::mpsc::{channel, Receiver};
+use std::sync::mpsc::TryRecvError::{Empty, Disconnected};
 use time;
 
 #[dom_struct]
@@ -71,18 +80,80 @@ pub struct Window {
     screen: MutNullableJS<Screen>,
     session_storage: MutNullableJS<Storage>,
     timers: TimerManager,
+
+    /// For providing instructions to an optional devtools server.
+    devtools_chan: Option<DevtoolsControlChan>,
+
+    /// A flag to indicate whether the developer tools have requested live updates of
+    /// page changes.
+    devtools_wants_updates: Cell<bool>,
+
+    next_subpage_id: Cell<SubpageId>,
+
+    /// Pending resize event, if any.
+    resize_event: Cell<Option<WindowSizeData>>,
+
+    /// Pipeline id associated with this page.
+    id: PipelineId,
+
+    /// Subpage id associated with this page, if any.
+    subpage_id: Option<SubpageId>,
+
+    /// Unique id for last reflow request; used for confirming completion reply.
+    last_reflow_id: Cell<uint>,
+
+    /// Global static data related to the DOM.
+    dom_static: GlobalStaticData,
+
+    /// The JavaScript context.
+    js_context: DOMRefCell<Option<Rc<Cx>>>,
+
+    /// A handle for communicating messages to the layout task.
+    layout_chan: LayoutChan,
+
+    /// A handle to perform RPC calls into the layout, quickly.
+    layout_rpc: Box<LayoutRPC+'static>,
+
+    /// The port that we will use to join layout. If this is `None`, then layout is not running.
+    layout_join_port: DOMRefCell<Option<Receiver<()>>>,
+
+    /// The current size of the window, in pixels.
+    window_size: Cell<WindowSizeData>,
+
+    /// Associated resource task for use by DOM objects like XMLHttpRequest
+    resource_task: ResourceTask,
+
+    /// A handle for communicating messages to the storage task.
+    storage_task: StorageTask,
+
+    /// A handle for communicating messages to the constellation task.
+    constellation_chan: ConstellationChan,
+
+    /// Pending scroll to fragment event, if any
+    fragment_name: DOMRefCell<Option<String>>,
+
+    /// An enlarged rectangle around the page contents visible in the viewport, used
+    /// to prevent creating display list items for content that is far away from the viewport.
+    page_clip_rect: Cell<Rect<Au>>,
 }
 
 impl Window {
     pub fn get_cx(&self) -> *mut JSContext {
-        let js_info = self.page().js_info();
-        (*js_info.as_ref().unwrap().js_context).ptr
+        self.js_context.borrow().as_ref().unwrap().ptr
     }
 
     pub fn script_chan(&self) -> Box<ScriptChan+Send> {
         self.script_chan.clone()
     }
 
+    pub fn pipeline(&self) -> PipelineId {
+        self.id.clone()
+    }
+
+    pub fn subpage(&self) -> Option<SubpageId> {
+        self.subpage_id.clone()
+    }
+
     pub fn control_chan<'a>(&'a self) -> &'a ScriptControlChan {
         &self.control_chan
     }
@@ -103,16 +174,8 @@ impl Window {
         &*self.page
     }
 
-    pub fn page_clone(&self) -> Rc<Page> {
-        self.page.clone()
-    }
-
-    pub fn get_url(&self) -> Url {
-        self.page().get_url()
-    }
-
     pub fn storage_task(&self) -> StorageTask {
-        self.page().storage_task.clone()
+        self.storage_task.clone()
     }
 }
 
@@ -197,12 +260,11 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
     }
 
     fn Close(self) {
-        self.script_chan.send(ScriptMsg::ExitWindow(self.page.id.clone())).unwrap();
+        self.script_chan.send(ScriptMsg::ExitWindow(self.id.clone())).unwrap();
     }
 
     fn Document(self) -> Temporary<Document> {
-        let frame = self.page().frame();
-        Temporary::new(frame.as_ref().unwrap().document.clone())
+        self.browser_context().as_ref().unwrap().active_document()
     }
 
     fn Location(self) -> Temporary<Location> {
@@ -230,7 +292,7 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
                                             args,
                                             timeout,
                                             IsInterval::NonInterval,
-                                            TimerSource::FromWindow(self.page.id.clone()),
+                                            TimerSource::FromWindow(self.id.clone()),
                                             self.script_chan.clone())
     }
 
@@ -239,7 +301,7 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
                                             args,
                                             timeout,
                                             IsInterval::NonInterval,
-                                            TimerSource::FromWindow(self.page.id.clone()),
+                                            TimerSource::FromWindow(self.id.clone()),
                                             self.script_chan.clone())
     }
 
@@ -252,7 +314,7 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
                                             args,
                                             timeout,
                                             IsInterval::Interval,
-                                            TimerSource::FromWindow(self.page.id.clone()),
+                                            TimerSource::FromWindow(self.id.clone()),
                                             self.script_chan.clone())
     }
 
@@ -261,7 +323,7 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
                                             args,
                                             timeout,
                                             IsInterval::Interval,
-                                            TimerSource::FromWindow(self.page.id.clone()),
+                                            TimerSource::FromWindow(self.id.clone()),
                                             self.script_chan.clone())
     }
 
@@ -330,10 +392,35 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
 }
 
 pub trait WindowHelpers {
+    fn clear_js_context(self);
+    fn clear_js_context_for_script_deallocation(self);
     fn flush_layout(self, goal: ReflowGoal, query: ReflowQueryType);
     fn init_browser_context(self, doc: JSRef<Document>, frame_element: Option<JSRef<Element>>);
     fn load_url(self, href: DOMString);
     fn handle_fire_timer(self, timer_id: TimerId);
+    fn reflow(self, goal: ReflowGoal, query_type: ReflowQueryType);
+    fn join_layout(self);
+    fn layout(&self) -> &LayoutRPC;
+    fn content_box_query(self, content_box_request: TrustedNodeAddress) -> Rect<Au>;
+    fn content_boxes_query(self, content_boxes_request: TrustedNodeAddress) -> Vec<Rect<Au>>;
+    fn handle_reflow_complete_msg(self, reflow_id: uint);
+    fn handle_resize_inactive_msg(self, new_size: WindowSizeData);
+    fn set_fragment_name(self, fragment: Option<String>);
+    fn steal_fragment_name(self) -> Option<String>;
+    fn set_window_size(self, size: WindowSizeData);
+    fn window_size(self) -> WindowSizeData;
+    fn get_url(self) -> Url;
+    fn resource_task(self) -> ResourceTask;
+    fn devtools_chan(self) -> Option<DevtoolsControlChan>;
+    fn layout_chan(self) -> LayoutChan;
+    fn constellation_chan(self) -> ConstellationChan;
+    fn windowproxy_handler(self) -> WindowProxyHandler;
+    fn get_next_subpage_id(self) -> SubpageId;
+    fn layout_is_idle(self) -> bool;
+    fn set_resize_event(self, event: WindowSizeData);
+    fn steal_resize_event(self) -> Option<WindowSizeData>;
+    fn set_page_clip_rect_with_new_viewport(self, viewport: Rect<f32>) -> bool;
+    fn set_devtools_wants_updates(self, value: bool);
     fn IndexedGetter(self, _index: u32, _found: &mut bool) -> Option<Temporary<Window>>;
     fn thaw(self);
     fn freeze(self);
@@ -373,8 +460,132 @@ impl<'a, T: Reflectable> ScriptHelpers for JSRef<'a, T> {
 }
 
 impl<'a> WindowHelpers for JSRef<'a, Window> {
+    fn clear_js_context(self) {
+        *self.js_context.borrow_mut() = None;
+        *self.browser_context.borrow_mut() = None;
+    }
+
+    #[allow(unsafe_blocks)]
+    fn clear_js_context_for_script_deallocation(self) {
+        unsafe {
+            *self.js_context.borrow_for_script_deallocation() = None;
+            *self.browser_context.borrow_for_script_deallocation() = None;
+        }
+    }
+
     fn flush_layout(self, goal: ReflowGoal, query: ReflowQueryType) {
-        self.page().flush_layout(goal, query);
+        self.reflow(goal, query);
+    }
+
+    /// Reflows the page if it's possible to do so and the page is dirty. This method will wait
+    /// for the layout thread to complete (but see the `TODO` below). If there is no window size
+    /// yet, the page is presumed invisible and no reflow is performed.
+    ///
+    /// TODO(pcwalton): Only wait for style recalc, since we have off-main-thread layout.
+    fn reflow(self, goal: ReflowGoal, query_type: ReflowQueryType) {
+        let document = self.Document().root();
+        let root = document.r().GetDocumentElement().root();
+        let root = match root.r() {
+            Some(root) => root,
+            None => return,
+        };
+
+        debug!("script: performing reflow for goal {:?}", goal);
+
+        let root: JSRef<Node> = NodeCast::from_ref(root);
+        if !root.get_has_dirty_descendants() {
+            debug!("root has no dirty descendants; avoiding reflow");
+            return
+        }
+
+        debug!("script: performing reflow for goal {:?}", goal);
+
+        // Layout will let us know when it's done.
+        let (join_chan, join_port) = channel();
+
+        {
+            let mut layout_join_port = self.layout_join_port.borrow_mut();
+            *layout_join_port = Some(join_port);
+        }
+
+        let last_reflow_id = &self.last_reflow_id;
+        last_reflow_id.set(last_reflow_id.get() + 1);
+
+        let window_size = self.window_size.get();
+
+        // Send new document and relevant styles to layout.
+        let reflow = box Reflow {
+            document_root: root.to_trusted_node_address(),
+            url: self.get_url(),
+            iframe: self.subpage_id.is_some(),
+            goal: goal,
+            window_size: window_size,
+            script_chan: self.control_chan.clone(),
+            script_join_chan: join_chan,
+            id: last_reflow_id.get(),
+            query_type: query_type,
+            page_clip_rect: self.page_clip_rect.get(),
+        };
+
+        let LayoutChan(ref chan) = self.layout_chan;
+        chan.send(Msg::Reflow(reflow)).unwrap();
+
+        debug!("script: layout forked");
+
+        self.join_layout();
+    }
+
+    // FIXME(cgaebel): join_layout is racey. What if the compositor triggers a
+    // reflow between the "join complete" message and returning from this
+    // function?
+
+    /// Sends a ping to layout and waits for the response. The response will arrive when the
+    /// layout task has finished any pending request messages.
+    fn join_layout(self) {
+        let mut layout_join_port = self.layout_join_port.borrow_mut();
+        if let Some(join_port) = replace(&mut *layout_join_port, None) {
+            match join_port.try_recv() {
+                Err(Empty) => {
+                    info!("script: waiting on layout");
+                    join_port.recv().unwrap();
+                }
+                Ok(_) => {}
+                Err(Disconnected) => {
+                    panic!("Layout task failed while script was waiting for a result.");
+                }
+            }
+
+            debug!("script: layout joined")
+        }
+    }
+
+    fn layout(&self) -> &LayoutRPC {
+        &*self.layout_rpc
+    }
+
+    fn content_box_query(self, content_box_request: TrustedNodeAddress) -> Rect<Au> {
+        self.flush_layout(ReflowGoal::ForScriptQuery, ReflowQueryType::ContentBoxQuery(content_box_request));
+        self.join_layout(); //FIXME: is this necessary, or is layout_rpc's mutex good enough?
+        let ContentBoxResponse(rect) = self.layout_rpc.content_box();
+        rect
+    }
+
+    fn content_boxes_query(self, content_boxes_request: TrustedNodeAddress) -> Vec<Rect<Au>> {
+        self.flush_layout(ReflowGoal::ForScriptQuery, ReflowQueryType::ContentBoxesQuery(content_boxes_request));
+        self.join_layout(); //FIXME: is this necessary, or is layout_rpc's mutex good enough?
+        let ContentBoxesResponse(rects) = self.layout_rpc.content_boxes();
+        rects
+    }
+
+    fn handle_reflow_complete_msg(self, reflow_id: uint) {
+        let last_reflow_id = self.last_reflow_id.get();
+        if last_reflow_id == reflow_id {
+            *self.layout_join_port.borrow_mut() = None;
+        }
+    }
+
+    fn handle_resize_inactive_msg(self, new_size: WindowSizeData) {
+        self.window_size.set(new_size);
     }
 
     fn init_browser_context(self, doc: JSRef<Document>, frame_element: Option<JSRef<Element>>) {
@@ -383,17 +594,17 @@ impl<'a> WindowHelpers for JSRef<'a, Window> {
 
     /// Commence a new URL load which will either replace this window or scroll to a fragment.
     fn load_url(self, href: DOMString) {
-        let base_url = self.page().get_url();
+        let base_url = self.get_url();
         debug!("current page url is {}", base_url);
         let url = UrlParser::new().base_url(&base_url).parse(href.as_slice());
         // FIXME: handle URL parse errors more gracefully.
         let url = url.unwrap();
         match url.fragment {
             Some(fragment) => {
-                self.script_chan.send(ScriptMsg::TriggerFragment(self.page.id, fragment)).unwrap();
+                self.script_chan.send(ScriptMsg::TriggerFragment(self.id, fragment)).unwrap();
             },
             None => {
-                self.script_chan.send(ScriptMsg::TriggerLoad(self.page.id, LoadData::new(url))).unwrap();
+                self.script_chan.send(ScriptMsg::TriggerLoad(self.id, LoadData::new(url))).unwrap();
             }
         }
     }
@@ -403,6 +614,97 @@ impl<'a> WindowHelpers for JSRef<'a, Window> {
         self.flush_layout(ReflowGoal::ForDisplay, ReflowQueryType::NoQuery);
     }
 
+    fn set_fragment_name(self, fragment: Option<String>) {
+        *self.fragment_name.borrow_mut() = fragment;
+    }
+
+    fn steal_fragment_name(self) -> Option<String> {
+        self.fragment_name.borrow_mut().take()
+    }
+
+    fn set_window_size(self, size: WindowSizeData) {
+        self.window_size.set(size);
+    }
+
+    fn window_size(self) -> WindowSizeData {
+        self.window_size.get()
+    }
+
+    fn get_url(self) -> Url {
+        let doc = self.Document().root();
+        doc.r().url()
+    }
+
+    fn resource_task(self) -> ResourceTask {
+        self.resource_task.clone()
+    }
+
+    fn devtools_chan(self) -> Option<DevtoolsControlChan> {
+        self.devtools_chan.clone()
+    }
+
+    fn layout_chan(self) -> LayoutChan {
+        self.layout_chan.clone()
+    }
+
+    fn constellation_chan(self) -> ConstellationChan {
+        self.constellation_chan.clone()
+    }
+
+    fn windowproxy_handler(self) -> WindowProxyHandler {
+        self.dom_static.windowproxy_handler
+    }
+
+    fn get_next_subpage_id(self) -> SubpageId {
+        let subpage_id = self.next_subpage_id.get();
+        let SubpageId(id_num) = subpage_id;
+        self.next_subpage_id.set(SubpageId(id_num + 1));
+        subpage_id
+    }
+
+    fn layout_is_idle(self) -> bool {
+        self.layout_join_port.borrow().is_none()
+    }
+
+    fn set_resize_event(self, event: WindowSizeData) {
+        self.resize_event.set(Some(event));
+    }
+
+    fn steal_resize_event(self) -> Option<WindowSizeData> {
+        let event = self.resize_event.get();
+        self.resize_event.set(None);
+        event
+    }
+
+    fn set_page_clip_rect_with_new_viewport(self, viewport: Rect<f32>) -> bool {
+        // We use a clipping rectangle that is five times the size of the of the viewport,
+        // so that we don't collect display list items for areas too far outside the viewport,
+        // but also don't trigger reflows every time the viewport changes.
+        static VIEWPORT_EXPANSION: f32 = 2.0; // 2 lengths on each side plus original length is 5 total.
+       let proposed_clip_rect = geometry::f32_rect_to_au_rect(
+           viewport.inflate(viewport.size.width * VIEWPORT_EXPANSION,
+           viewport.size.height * VIEWPORT_EXPANSION));
+       let clip_rect = self.page_clip_rect.get();
+       if proposed_clip_rect == clip_rect {
+           return false;
+       }
+
+       let had_clip_rect = clip_rect != MAX_RECT;
+       if had_clip_rect && !should_move_clip_rect(clip_rect, viewport) {
+           return false;
+       }
+
+       self.page_clip_rect.set(proposed_clip_rect);
+
+       // If we didn't have a clip rect, the previous display doesn't need rebuilding
+       // because it was built for infinite clip (MAX_RECT).
+       had_clip_rect
+   }
+
+   fn set_devtools_wants_updates(self, value: bool) {
+       self.devtools_wants_updates.set(value);
+   }
+
     // https://html.spec.whatwg.org/multipage/browsers.html#accessing-other-browsing-contexts
     fn IndexedGetter(self, _index: u32, _found: &mut bool) -> Option<Temporary<Window>> {
         None
@@ -419,13 +721,28 @@ impl<'a> WindowHelpers for JSRef<'a, Window> {
 }
 
 impl Window {
-    pub fn new(cx: *mut JSContext,
+    pub fn new(js_context: Rc<Cx>,
                page: Rc<Page>,
                script_chan: Box<ScriptChan+Send>,
                control_chan: ScriptControlChan,
                compositor: Box<ScriptListener+'static>,
-               image_cache_task: ImageCacheTask)
+               image_cache_task: ImageCacheTask,
+               resource_task: ResourceTask,
+               storage_task: StorageTask,
+               devtools_chan: Option<DevtoolsControlChan>,
+               constellation_chan: ConstellationChan,
+               layout_chan: LayoutChan,
+               id: PipelineId,
+               subpage_id: Option<SubpageId>,
+               window_size: WindowSizeData)
                -> Temporary<Window> {
+        let layout_rpc: Box<LayoutRPC> = {
+            let (rpc_send, rpc_recv) = channel();
+            let LayoutChan(ref lchan) = layout_chan;
+            lchan.send(Msg::GetRPC(rpc_send)).unwrap();
+            rpc_recv.recv().unwrap()
+        };
+
         let win = box Window {
             eventtarget: EventTarget::new_inherited(EventTargetTypeId::Window),
             script_chan: script_chan,
@@ -435,6 +752,7 @@ impl Window {
             page: page,
             navigator: Default::default(),
             image_cache_task: image_cache_task,
+            devtools_chan: devtools_chan,
             browser_context: DOMRefCell::new(None),
             performance: Default::default(),
             navigation_start: time::get_time().sec as u64,
@@ -442,8 +760,43 @@ impl Window {
             screen: Default::default(),
             session_storage: Default::default(),
             timers: TimerManager::new(),
+            id: id,
+            subpage_id: subpage_id,
+            dom_static: GlobalStaticData::new(),
+            js_context: DOMRefCell::new(Some(js_context.clone())),
+            resource_task: resource_task,
+            storage_task: storage_task,
+            constellation_chan: constellation_chan,
+            page_clip_rect: Cell::new(MAX_RECT),
+            fragment_name: DOMRefCell::new(None),
+            last_reflow_id: Cell::new(0),
+            resize_event: Cell::new(None),
+            next_subpage_id: Cell::new(SubpageId(0)),
+            layout_chan: layout_chan,
+            layout_rpc: layout_rpc,
+            layout_join_port: DOMRefCell::new(None),
+            window_size: Cell::new(window_size),
+            devtools_wants_updates: Cell::new(false),
         };
 
-        WindowBinding::Wrap(cx, win)
+        WindowBinding::Wrap(js_context.ptr, win)
     }
 }
+
+fn should_move_clip_rect(clip_rect: Rect<Au>, new_viewport: Rect<f32>) -> bool{
+    let clip_rect = Rect(Point2D(geometry::to_frac_px(clip_rect.origin.x) as f32,
+                                 geometry::to_frac_px(clip_rect.origin.y) as f32),
+                         Size2D(geometry::to_frac_px(clip_rect.size.width) as f32,
+                                geometry::to_frac_px(clip_rect.size.height) as f32));
+
+    // We only need to move the clip rect if the viewport is getting near the edge of
+    // our preexisting clip rect. We use half of the size of the viewport as a heuristic
+    // for "close."
+    static VIEWPORT_SCROLL_MARGIN_SIZE: f32 = 0.5;
+    let viewport_scroll_margin = new_viewport.size * VIEWPORT_SCROLL_MARGIN_SIZE;
+
+    (clip_rect.origin.x - new_viewport.origin.x).abs() <= viewport_scroll_margin.width ||
+    (clip_rect.max_x() - new_viewport.max_x()).abs() <= viewport_scroll_margin.width ||
+    (clip_rect.origin.y - new_viewport.origin.y).abs() <= viewport_scroll_margin.height ||
+    (clip_rect.max_y() - new_viewport.max_y()).abs() <= viewport_scroll_margin.height
+}