mus: Server-side implementation of modal windows

components/mus/ws/server_window.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/mus/ws/server_window.h"
 
 #include <inttypes.h>
 #include <stddef.h>
 
 #include "base/strings/stringprintf.h"
 #include "components/mus/common/transient_window_utils.h"
 #include "components/mus/ws/server_window_delegate.h"
 #include "components/mus/ws/server_window_observer.h"
 #include "components/mus/ws/server_window_surface_manager.h"
 #include "mojo/converters/geometry/geometry_type_converters.h"
 
 namespace mus {
 
 namespace ws {
 
+namespace {
+
+const ServerWindow* GetModalChildForWindowAncestor(const ServerWindow* window) {
+  for (const ServerWindow* ancestor = window; ancestor;
+       ancestor = ancestor->parent()) {
+    for (const auto& transient_child : ancestor->transient_children()) {
+      if (transient_child->is_modal() && transient_child->IsDrawn())
+        return transient_child;
+    }
+  }
+  return nullptr;
+}
+
+const ServerWindow* GetModalTargetForWindow(const ServerWindow* window) {
+  const ServerWindow* modal_window = GetModalChildForWindowAncestor(window);
+  if (!modal_window)
+    return window;
+  return GetModalTargetForWindow(modal_window);
+}
+
+}  // namespace
+
 ServerWindow::ServerWindow(ServerWindowDelegate* delegate, const WindowId& id)
     : ServerWindow(delegate, id, Properties()) {}
 
 ServerWindow::ServerWindow(ServerWindowDelegate* delegate,
                            const WindowId& id,
                            const Properties& properties)
     : delegate_(delegate),
       id_(id),
       parent_(nullptr),
       stacking_target_(nullptr),
       transient_parent_(nullptr),
+      is_modal_(false),
       visible_(false),
       cursor_id_(mojom::Cursor::CURSOR_NULL),
       opacity_(1),
       can_focus_(true),
       properties_(properties),
       // Don't notify newly added observers during notification. This causes
       // problems for code that adds an observer as part of an observer
       // notification (such as ServerWindowDrawTracker).
       observers_(
           base::ObserverList<ServerWindowObserver>::NOTIFY_EXISTING_ONLY) {
@@ skipping 192 matching lines @@
   // If |child| and its former transient parent share the same parent, |child|
   // should be restacked properly so it is not among transient children of its
   // former parent, anymore.
   if (parent() == child->parent())
     RestackTransientDescendants(this, &GetStackingTarget, &ReorderImpl);
 
   FOR_EACH_OBSERVER(ServerWindowObserver, observers_,
                     OnTransientWindowRemoved(this, child));
 }
 
+void ServerWindow::SetModal() {
+  is_modal_ = true;
+}
+
+bool ServerWindow::IsBlockedByModalWindow() const {
+  return !!GetModalChildForWindowAncestor(this);
+}
+
+const ServerWindow* ServerWindow::GetModalTarget() const {
+  return GetModalTargetForWindow(this);
+}
+
 bool ServerWindow::Contains(const ServerWindow* window) const {
   for (const ServerWindow* parent = window; parent; parent = parent->parent_) {
     if (parent == this)
       return true;
   }
   return false;
 }
 
 void ServerWindow::SetVisible(bool value) {
   if (visible_ == value)
@@ skipping 167 matching lines @@
 }
 
 // static
 ServerWindow** ServerWindow::GetStackingTarget(ServerWindow* window) {
   return &window->stacking_target_;
 }
 
 }  // namespace ws
 
 }  // namespace mus