1 files changed, 84 insertions, 0 deletions
diff --git a/layout/style/TimelineManager.h b/layout/style/TimelineManager.h
new file mode 100644
index 0000000000..f52302a661
--- /dev/null
+++ b/layout/style/TimelineManager.h
@@ -0,0 +1,84 @@
+/* -*- 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/. */
+#ifndef mozilla_TimelineManager_h
+#define mozilla_TimelineManager_h
+
+#include "mozilla/Assertions.h"
+#include "mozilla/LinkedList.h"
+#include "mozilla/TimelineCollection.h"
+#include "nsStyleAutoArray.h"
+
+class nsPresContext;
+
+namespace mozilla {
+class ComputedStyle;
+enum class PseudoStyleType : uint8_t;
+
+namespace dom {
+class Element;
+class ScrollTimeline;
+class ViewTimeline;
+}  // namespace dom
+
+class TimelineManager {
+ public:
+  explicit TimelineManager(nsPresContext* aPresContext)
+      : mPresContext(aPresContext) {}
+
+  ~TimelineManager() {
+    MOZ_ASSERT(!mPresContext, "Disconnect should have been called");
+  }
+
+  void Disconnect() {
+    while (auto* head = mScrollTimelineCollections.getFirst()) {
+      head->Destroy();
+    }
+    while (auto* head = mViewTimelineCollections.getFirst()) {
+      head->Destroy();
+    }
+
+    mPresContext = nullptr;
+  }
+
+  enum class ProgressTimelineType : uint8_t {
+    Scroll,
+    View,
+  };
+  void UpdateTimelines(dom::Element* aElement, PseudoStyleType aPseudoType,
+                       const ComputedStyle* aComputedStyle,
+                       ProgressTimelineType aType);
+
+ private:
+  template <typename StyleType, typename TimelineType>
+  void DoUpdateTimelines(nsPresContext* aPresContext, dom::Element* aElement,
+                         PseudoStyleType aPseudoType,
+                         const nsStyleAutoArray<StyleType>& aStyleTimelines,
+                         size_t aTimelineCount);
+
+  template <typename T>
+  void AddTimelineCollection(TimelineCollection<T>* aCollection);
+
+  LinkedList<TimelineCollection<dom::ScrollTimeline>>
+      mScrollTimelineCollections;
+  LinkedList<TimelineCollection<dom::ViewTimeline>> mViewTimelineCollections;
+  nsPresContext* mPresContext;
+};
+
+template <>
+inline void TimelineManager::AddTimelineCollection(
+    TimelineCollection<dom::ScrollTimeline>* aCollection) {
+  mScrollTimelineCollections.insertBack(aCollection);
+}
+
+template <>
+inline void TimelineManager::AddTimelineCollection(
+    TimelineCollection<dom::ViewTimeline>* aCollection) {
+  mViewTimelineCollections.insertBack(aCollection);
+}
+
+}  // namespace mozilla
+
+#endif  // mozilla_TimelineManager_h