1 files changed, 139 insertions, 0 deletions
diff --git a/dom/svg/SVGSwitchElement.cpp b/dom/svg/SVGSwitchElement.cpp
new file mode 100644
index 0000000000..e049d07496
--- /dev/null
+++ b/dom/svg/SVGSwitchElement.cpp
@@ -0,0 +1,139 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/SVGSwitchElement.h"
+
+#include "nsLayoutUtils.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/SVGUtils.h"
+#include "mozilla/dom/SVGSwitchElementBinding.h"
+
+class nsIFrame;
+
+NS_IMPL_NS_NEW_SVG_ELEMENT(Switch)
+
+namespace mozilla::dom {
+
+JSObject* SVGSwitchElement::WrapNode(JSContext* aCx,
+                                     JS::Handle<JSObject*> aGivenProto) {
+  return SVGSwitchElement_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+//----------------------------------------------------------------------
+// nsISupports methods
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(SVGSwitchElement, SVGSwitchElementBase,
+                                   mActiveChild)
+
+NS_IMPL_ADDREF_INHERITED(SVGSwitchElement, SVGSwitchElementBase)
+NS_IMPL_RELEASE_INHERITED(SVGSwitchElement, SVGSwitchElementBase)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(SVGSwitchElement)
+NS_INTERFACE_MAP_END_INHERITING(SVGSwitchElementBase)
+
+//----------------------------------------------------------------------
+// Implementation
+
+SVGSwitchElement::SVGSwitchElement(
+    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
+    : SVGSwitchElementBase(std::move(aNodeInfo)) {}
+
+void SVGSwitchElement::MaybeInvalidate() {
+  // We must not change mActiveChild until after
+  // InvalidateAndScheduleBoundsUpdate has been called, otherwise
+  // it will not correctly invalidate the old mActiveChild area.
+
+  nsIContent* newActiveChild = FindActiveChild();
+
+  if (newActiveChild == mActiveChild) {
+    return;
+  }
+
+  nsIFrame* frame = GetPrimaryFrame();
+  if (frame) {
+    nsLayoutUtils::PostRestyleEvent(this, RestyleHint{0},
+                                    nsChangeHint_InvalidateRenderingObservers);
+    SVGUtils::ScheduleReflowSVG(frame);
+  }
+
+  mActiveChild = newActiveChild;
+}
+
+//----------------------------------------------------------------------
+// nsINode methods
+
+NS_IMPL_ELEMENT_CLONE_WITH_INIT(SVGSwitchElement)
+
+//----------------------------------------------------------------------
+// nsINode methods
+
+void SVGSwitchElement::InsertChildBefore(nsIContent* aKid,
+                                         nsIContent* aBeforeThis, bool aNotify,
+                                         ErrorResult& aRv) {
+  SVGSwitchElementBase::InsertChildBefore(aKid, aBeforeThis, aNotify, aRv);
+  if (aRv.Failed()) {
+    return;
+  }
+
+  MaybeInvalidate();
+}
+
+void SVGSwitchElement::RemoveChildNode(nsIContent* aKid, bool aNotify) {
+  SVGSwitchElementBase::RemoveChildNode(aKid, aNotify);
+  MaybeInvalidate();
+}
+
+//----------------------------------------------------------------------
+// Implementation Helpers:
+
+nsIContent* SVGSwitchElement::FindActiveChild() const {
+  nsAutoString acceptLangs;
+  Preferences::GetLocalizedString("intl.accept_languages", acceptLangs);
+
+  int32_t bestLanguagePreferenceRank = -1;
+  nsIContent* bestChild = nullptr;
+  nsIContent* defaultChild = nullptr;
+  for (nsIContent* child = nsINode::GetFirstChild(); child;
+       child = child->GetNextSibling()) {
+    if (!child->IsElement()) {
+      continue;
+    }
+    nsCOMPtr<SVGTests> tests(do_QueryInterface(child));
+    if (tests) {
+      if (tests->PassesConditionalProcessingTestsIgnoringSystemLanguage()) {
+        int32_t languagePreferenceRank =
+            tests->GetBestLanguagePreferenceRank(acceptLangs);
+        switch (languagePreferenceRank) {
+          case 0:
+            // best possible match
+            return child;
+          case -1:
+            // no match
+            break;
+          case -2:
+            // no systemLanguage attribute. If there's nothing better
+            // we'll use the first such child.
+            if (!defaultChild) {
+              defaultChild = child;
+            }
+            break;
+          default:
+            if (bestLanguagePreferenceRank == -1 ||
+                languagePreferenceRank < bestLanguagePreferenceRank) {
+              bestLanguagePreferenceRank = languagePreferenceRank;
+              bestChild = child;
+            }
+            break;
+        }
+      }
+    } else if (!bestChild) {
+      bestChild = child;
+    }
+  }
+  return bestChild ? bestChild : defaultChild;
+}
+
+}  // namespace mozilla::dom