LibWeb: Add Page abstraction between PageView and main Frame

* A PageView is a view onto a Page object.
* A Page always has a main Frame (root of Frame tree.)
* Page has a PageClient. PageView is a PageClient.

The goal here is to allow building another kind of view onto
a Page while keeping the rest of LibWeb intact.

Libraries/LibWeb/Frame/EventHandler.cpp

@@ -105,7 +105,7 @@ bool EventHandler::handle_mousedown(const Gfx::Point& position, unsigned button,
         return false;
     auto& layout_root = *layout_root_ptr;
     auto& document = *m_frame.document();
-    auto& page_view = *m_frame.page_view();
+    auto& page_client = m_frame.page().client();
 
     auto result = layout_root.hit_test(position);
     if (!result.layout_node)
@@ -133,16 +133,16 @@ bool EventHandler::handle_mousedown(const Gfx::Point& position, unsigned button,
                 document.run_javascript(href.substring_view(11, href.length() - 11));
             } else {
                 if (m_frame.is_main_frame()) {
-                    page_view.notify_link_click({}, m_frame, link->href(), link->target(), modifiers);
+                    page_client.page_did_click_link(link->href(), link->target(), modifiers);
                 } else {
                     // FIXME: Handle different targets!
                     m_frame.loader().load(document.complete_url(link->href()));
                 }
             }
         } else if (button == GUI::MouseButton::Right) {
-            page_view.notify_link_context_menu_request({}, m_frame, position, link->href(), link->target(), modifiers);
+            page_client.page_did_request_link_context_menu(m_frame.to_main_frame_position(position), link->href(), link->target(), modifiers);
         } else if (button == GUI::MouseButton::Middle) {
-            page_view.notify_link_middle_click({}, m_frame, link->href(), link->target(), modifiers);
+            page_client.page_did_middle_click_link(link->href(), link->target(), modifiers);
         }
     } else {
         if (button == GUI::MouseButton::Left) {
@@ -161,7 +161,7 @@ bool EventHandler::handle_mousemove(const Gfx::Point& position, unsigned buttons
         return false;
     auto& layout_root = *layout_root_ptr;
     auto& document = *m_frame.document();
-    auto& page_view = *m_frame.page_view();
+    auto& page_client = m_frame.page().client();
 
     bool hovered_node_changed = false;
     bool is_hovering_link = false;
@@ -193,22 +193,23 @@ bool EventHandler::handle_mousemove(const Gfx::Point& position, unsigned buttons
         if (m_in_mouse_selection) {
             layout_root.selection().set_end({ result.layout_node, result.index_in_node });
             dump_selection("MouseMove");
-            page_view.update();
+            page_client.page_did_change_selection();
         }
     }
-    if (page_view.window())
-        page_view.window()->set_override_cursor(is_hovering_link ? GUI::StandardCursor::Hand : GUI::StandardCursor::None);
+    page_client.page_did_request_cursor_change(is_hovering_link ? GUI::StandardCursor::Hand : GUI::StandardCursor::None);
     if (hovered_node_changed) {
-        page_view.update();
         RefPtr<HTMLElement> hovered_html_element = document.hovered_node() ? document.hovered_node()->enclosing_html_element() : nullptr;
         if (hovered_html_element && !hovered_html_element->title().is_null()) {
-            page_view.notify_tooltip_area_enter({}, m_frame, position, hovered_html_element->title());
+            page_client.page_did_enter_tooltip_area(m_frame.to_main_frame_position(position), hovered_html_element->title());
         } else {
-            page_view.notify_tooltip_area_leave({}, m_frame);
+            page_client.page_did_leave_tooltip_area();
         }
     }
     if (is_hovering_link != was_hovering_link) {
-        page_view.notify_link_hover({}, m_frame, hovered_link_element ? document.complete_url(hovered_link_element->href()).to_string() : String());
+        if (is_hovering_link)
+            page_client.page_did_hover_link(document.complete_url(hovered_link_element->href()));
+        else
+            page_client.page_did_unhover_link();
     }
     return true;
 }

Libraries/LibWeb/Frame/Frame.cpp

@@ -33,18 +33,19 @@
 namespace Web {
 
 Frame::Frame(Element& host_element, Frame& main_frame)
-    : m_main_frame(main_frame)
+    : m_page(main_frame.page())
+    , m_main_frame(main_frame)
     , m_loader(*this)
     , m_event_handler({}, *this)
     , m_host_element(host_element.make_weak_ptr())
 {
 }
 
-Frame::Frame(PageView& page_view)
-    : m_main_frame(*this)
+Frame::Frame(Page& page)
+    : m_page(page)
+    , m_main_frame(*this)
     , m_loader(*this)
     , m_event_handler({}, *this)
-    , m_page_view(page_view.make_weak_ptr())
 {
 }
 
@@ -94,8 +95,7 @@ void Frame::set_needs_display(const Gfx::Rect& rect)
         return;
 
     if (is_main_frame()) {
-        if (page_view())
-            page_view()->notify_needs_display({}, *this, rect);
+        page().client().page_did_invalidate(to_main_frame_rect(rect));
         return;
     }
 
@@ -117,12 +117,31 @@ void Frame::did_scroll(Badge<PageView>)
 
 void Frame::scroll_to_anchor(const String& fragment)
 {
-    // FIXME: We should be able to scroll iframes to an anchor, too!
-    if (!m_page_view)
-        return;
     // FIXME: This logic is backwards, the work should be done in here,
     //        and then we just request that the "view" scrolls to a certain content offset.
-    m_page_view->scroll_to_anchor(fragment);
+    page().client().page_did_request_scroll_to_anchor(fragment);
+}
+
+Gfx::Rect Frame::to_main_frame_rect(const Gfx::Rect& a_rect)
+{
+    auto rect = a_rect;
+    rect.set_location(to_main_frame_position(a_rect.location()));
+    return rect;
+}
+
+Gfx::Point Frame::to_main_frame_position(const Gfx::Point& a_position)
+{
+    auto position = a_position;
+    for (auto* ancestor = parent(); ancestor; ancestor = ancestor->parent()) {
+        if (ancestor->is_main_frame())
+            break;
+        if (!ancestor->host_element())
+            return {};
+        if (!ancestor->host_element()->layout_node())
+            return {};
+        position.move_by(ancestor->host_element()->layout_node()->box_type_agnostic_position().to_int_point());
+    }
+    return position;
 }
 
 }

Libraries/LibWeb/Frame/Frame.h

@@ -42,7 +42,7 @@ namespace Web {
 class Frame : public TreeNode<Frame> {
 public:
     static NonnullRefPtr<Frame> create_subframe(Element& host_element, Frame& main_frame) { return adopt(*new Frame(host_element, main_frame)); }
-    static NonnullRefPtr<Frame> create(PageView& page_view) { return adopt(*new Frame(page_view)); }
+    static NonnullRefPtr<Frame> create(Page& page) { return adopt(*new Frame(page)); }
     ~Frame();
 
     bool is_main_frame() const { return this == &m_main_frame; }
@@ -52,8 +52,8 @@ public:
 
     void set_document(Document*);
 
-    PageView* page_view() { return is_main_frame() ? m_page_view : main_frame().m_page_view; }
-    const PageView* page_view() const { return is_main_frame() ? m_page_view : main_frame().m_page_view; }
+    Page& page() { return m_page; }
+    const Page& page() const { return m_page; }
 
     const Gfx::Size& size() const { return m_size; }
     void set_size(const Gfx::Size&);
@@ -84,17 +84,20 @@ public:
     Element* host_element() { return m_host_element; }
     const Element* host_element() const { return m_host_element; }
 
+    Gfx::Point to_main_frame_position(const Gfx::Point&);
+    Gfx::Rect to_main_frame_rect(const Gfx::Rect&);
+
 private:
     explicit Frame(Element& host_element, Frame& main_frame);
-    explicit Frame(PageView&);
+    explicit Frame(Page&);
 
+    Page& m_page;
     Frame& m_main_frame;
 
     FrameLoader m_loader;
     EventHandler m_event_handler;
 
     WeakPtr<Element> m_host_element;
-    WeakPtr<PageView> m_page_view;
     RefPtr<Document> m_document;
     Gfx::Size m_size;
     Gfx::Rect m_viewport_rect;