Basic support for animating window properties in Mus.

components/mus/ws/animation_runner.cc

Index: components/mus/ws/animation_runner.cc
diff --git a/components/mus/ws/animation_runner.cc b/components/mus/ws/animation_runner.cc
new file mode 100644
index 0000000000000000000000000000000000000000..080fb2c0f45cde3c4b9e8077d5269f390f39c76e
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+++ b/components/mus/ws/animation_runner.cc
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+// 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/animation_runner.h"
+
+#include "base/memory/scoped_vector.h"
+#include "components/mus/ws/animation_runner_observer.h"
+#include "components/mus/ws/scheduled_animation_group.h"
+#include "components/mus/ws/server_window.h"
+
+namespace mus {
+namespace ws {
+namespace {
+
+bool ConvertWindowAndAnimationPairsToScheduledAnimationGroups(
+    const std::vector<AnimationRunner::WindowAndAnimationPair>& pairs,
+    AnimationRunner::AnimationId id,
+    base::TimeTicks now,
+    std::vector<std::unique_ptr<ScheduledAnimationGroup>>* groups) {
+  for (const auto& window_animation_pair : pairs) {
+    DCHECK(window_animation_pair.first);
+    DCHECK(window_animation_pair.second);
+    std::unique_ptr<ScheduledAnimationGroup> group(
+        ScheduledAnimationGroup::Create(window_animation_pair.first, now, id,
+                                        *(window_animation_pair.second)));
+    if (!group.get())
+      return false;
+    groups->push_back(std::move(group));
+  }
+  return true;
+}
+
+}  // namespace
+
+AnimationRunner::AnimationRunner(base::TimeTicks now)
+    : next_id_(1), last_tick_time_(now) {}
+
+AnimationRunner::~AnimationRunner() {}
+
+void AnimationRunner::AddObserver(AnimationRunnerObserver* observer) {
+  observers_.AddObserver(observer);
+}
+
+void AnimationRunner::RemoveObserver(AnimationRunnerObserver* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+AnimationRunner::AnimationId AnimationRunner::Schedule(
+    const std::vector<WindowAndAnimationPair>& pairs,
+    base::TimeTicks now) {
+  DCHECK_GE(now, last_tick_time_);
+
+  const AnimationId animation_id = next_id_++;
+  std::vector<std::unique_ptr<ScheduledAnimationGroup>> groups;
+  if (!ConvertWindowAndAnimationPairsToScheduledAnimationGroups(
+          pairs, animation_id, now, &groups)) {
+    return 0;
+  }
+
+  // Cancel any animations for the affected windows. If the cancelled animations
+  // also animated properties that are not animated by the new group - instantly
+  // set those to the target value.
+  for (auto& group : groups) {
+    ScheduledAnimationGroup* current_group =
+        window_to_animation_map_[group->window()].get();
+    if (current_group)
+      current_group->SetValuesToTargetValuesForPropertiesNotIn(*group.get());
+
+    CancelAnimationForWindowImpl(group->window(), CANCEL_SOURCE_SCHEDULE);
+  }
+
+  // Update internal maps
+  for (auto& group : groups) {
+    group->ObtainStartValues();
+    ServerWindow* window = group->window();
+    window_to_animation_map_[window] = std::move(group);
+    DCHECK(!id_to_windows_map_[animation_id].count(window));
+    id_to_windows_map_[animation_id].insert(window);
+  }
+
+  FOR_EACH_OBSERVER(AnimationRunnerObserver, observers_,
+                    OnAnimationScheduled(animation_id));
+  return animation_id;
+}
+
+void AnimationRunner::CancelAnimation(AnimationId id) {
+  if (id_to_windows_map_.count(id) == 0)
+    return;
+
+  std::set<ServerWindow*> windows(id_to_windows_map_[id]);
+  for (ServerWindow* window : windows)
+    CancelAnimationForWindow(window);
+}
+
+void AnimationRunner::CancelAnimationForWindow(ServerWindow* window) {
+  CancelAnimationForWindowImpl(window, CANCEL_SOURCE_CANCEL);
+}
+
+void AnimationRunner::Tick(base::TimeTicks time) {
+  DCHECK(time >= last_tick_time_);
+  last_tick_time_ = time;
+  if (window_to_animation_map_.empty())
+    return;
+
+  // The animation ids of any windows whose animation completes are added here.
+  // We notify after processing all windows so that if an observer mutates us in
+  // some way we're aren't left in a weird state.
+  std::set<AnimationId> animations_completed;
+  for (WindowToAnimationMap::iterator i = window_to_animation_map_.begin();
+       i != window_to_animation_map_.end();) {
+    bool animation_done = i->second->Tick(time);
+    if (animation_done) {
+      const AnimationId animation_id = i->second->id();
+      ServerWindow* window = i->first;
+      ++i;
+      bool animation_completed = RemoveWindowFromMaps(window);
+      if (animation_completed)
+        animations_completed.insert(animation_id);
+    } else {
+      ++i;
+    }
+  }
+  for (const AnimationId& id : animations_completed) {
+    FOR_EACH_OBSERVER(AnimationRunnerObserver, observers_, OnAnimationDone(id));
+  }
+}
+
+void AnimationRunner::CancelAnimationForWindowImpl(ServerWindow* window,
+                                                   CancelSource source) {
+  if (!window_to_animation_map_[window])
+    return;
+
+  const AnimationId animation_id = window_to_animation_map_[window]->id();
+  if (RemoveWindowFromMaps(window)) {
+    // This was the last window in the group.
+    if (source == CANCEL_SOURCE_CANCEL) {
+      FOR_EACH_OBSERVER(AnimationRunnerObserver, observers_,
+                        OnAnimationCanceled(animation_id));
+    } else {
+      FOR_EACH_OBSERVER(AnimationRunnerObserver, observers_,
+                        OnAnimationInterrupted(animation_id));
+    }
+  }
+}
+
+bool AnimationRunner::RemoveWindowFromMaps(ServerWindow* window) {
+  DCHECK(window_to_animation_map_[window]);
+
+  const AnimationId animation_id = window_to_animation_map_[window]->id();
+  window_to_animation_map_.erase(window);
+
+  DCHECK(id_to_windows_map_.count(animation_id));
+  id_to_windows_map_[animation_id].erase(window);
+  if (!id_to_windows_map_[animation_id].empty())
+    return false;
+
+  id_to_windows_map_.erase(animation_id);
+  return true;
+}
+
+}  // namespace ws
+}  // namespace mus