Reapply and fix r73019. BalloonViewImpl has a different implemementation on

chrome/browser/notifications/balloon_collection_impl.cc

+// Copyright (c) 2010 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 "chrome/browser/notifications/balloon_collection_impl.h"
+
+#include "base/logging.h"
+#include "base/stl_util-inl.h"
+#include "chrome/browser/notifications/balloon.h"
+#include "chrome/browser/notifications/balloon_host.h"
+#include "chrome/browser/notifications/notification.h"
+#include "chrome/browser/ui/window_sizer.h"
+#include "gfx/rect.h"
+#include "gfx/size.h"
+
+namespace {
+
+// Portion of the screen allotted for notifications. When notification balloons
+// extend over this, no new notifications are shown until some are closed.
+const double kPercentBalloonFillFactor = 0.7;
+
+// Allow at least this number of balloons on the screen.
+const int kMinAllowedBalloonCount = 2;
+
+// Delay from the mouse leaving the balloon collection before
+// there is a relayout, in milliseconds.
+const int kRepositionDelay = 300;
+
+}  // namespace
+
+BalloonCollectionImpl::BalloonCollectionImpl()
+#if USE_OFFSETS
+    : ALLOW_THIS_IN_INITIALIZER_LIST(reposition_factory_(this)),
+      added_as_message_loop_observer_(false)
+#endif
+{
+
+  SetPositionPreference(BalloonCollection::DEFAULT_POSITION);
+}
+
+BalloonCollectionImpl::~BalloonCollectionImpl() {
+}
+
+void BalloonCollectionImpl::Add(const Notification& notification,
+                                Profile* profile) {
+  Balloon* new_balloon = MakeBalloon(notification, profile);
+  // The +1 on width is necessary because width is fixed on notifications,
+  // so since we always have the max size, we would always hit the scrollbar
+  // condition.  We are only interested in comparing height to maximum.
+  new_balloon->set_min_scrollbar_size(gfx::Size(1 + layout_.max_balloon_width(),
+                                                layout_.max_balloon_height()));
+  new_balloon->SetPosition(layout_.OffScreenLocation(), false);
+  new_balloon->Show();
+#if USE_OFFSETS
+  int count = base_.count();
+  if (count > 0 && layout_.RequiresOffsets())
+    new_balloon->set_offset(base_.balloons()[count - 1]->offset());
+#endif
+  base_.Add(new_balloon);
+  PositionBalloons(false);
+
+  // There may be no listener in a unit test.
+  if (space_change_listener_)
+    space_change_listener_->OnBalloonSpaceChanged();
+
+  // This is used only for testing.
+  if (on_collection_changed_callback_.get())
+    on_collection_changed_callback_->Run();
+}
+
+bool BalloonCollectionImpl::RemoveById(const std::string& id) {
+  return base_.CloseById(id);
+}
+
+bool BalloonCollectionImpl::RemoveBySourceOrigin(const GURL& origin) {
+  return base_.CloseAllBySourceOrigin(origin);
+}
+
+void BalloonCollectionImpl::RemoveAll() {
+  base_.CloseAll();
+}
+
+bool BalloonCollectionImpl::HasSpace() const {
+  int count = base_.count();
+  if (count < kMinAllowedBalloonCount)
+    return true;
+
+  int max_balloon_size = 0;
+  int total_size = 0;
+  layout_.GetMaxLinearSize(&max_balloon_size, &total_size);
+
+  int current_max_size = max_balloon_size * count;
+  int max_allowed_size = static_cast<int>(total_size *
+                                          kPercentBalloonFillFactor);
+  return current_max_size < max_allowed_size - max_balloon_size;
+}
+
+void BalloonCollectionImpl::ResizeBalloon(Balloon* balloon,
+                                          const gfx::Size& size) {
+  balloon->set_content_size(Layout::ConstrainToSizeLimits(size));
+  PositionBalloons(true);
+}
+
+void BalloonCollectionImpl::DisplayChanged() {
+  layout_.RefreshSystemMetrics();
+  PositionBalloons(true);
+}
+
+void BalloonCollectionImpl::OnBalloonClosed(Balloon* source) {
+  // We want to free the balloon when finished.
+  const Balloons& balloons = base_.balloons();
+  Balloons::const_iterator it = balloons.begin();
+
+#if USE_OFFSETS
+  if (layout_.RequiresOffsets()) {
+    gfx::Point offset;
+    bool apply_offset = false;
+    while (it != balloons.end()) {
+      if (*it == source) {
+        ++it;
+        if (it != balloons.end()) {
+          apply_offset = true;
+          offset.set_y((source)->offset().y() - (*it)->offset().y() +
+              (*it)->content_size().height() - source->content_size().height());
+        }
+      } else {
+        if (apply_offset)
+          (*it)->add_offset(offset);
+        ++it;
+      }
+    }
+    // Start listening for UI events so we cancel the offset when the mouse
+    // leaves the balloon area.
+    if (apply_offset)
+      AddMessageLoopObserver();
+  }
+#endif
+
+  base_.Remove(source);
+  PositionBalloons(true);
+
+  // There may be no listener in a unit test.
+  if (space_change_listener_)
+    space_change_listener_->OnBalloonSpaceChanged();
+
+  // This is used only for testing.
+  if (on_collection_changed_callback_.get())
+    on_collection_changed_callback_->Run();
+}
+
+const BalloonCollection::Balloons& BalloonCollectionImpl::GetActiveBalloons() {
+  return base_.balloons();
+}
+
+void BalloonCollectionImpl::PositionBalloonsInternal(bool reposition) {
+  const Balloons& balloons = base_.balloons();
+
+  layout_.RefreshSystemMetrics();
+  gfx::Point origin = layout_.GetLayoutOrigin();
+  for (Balloons::const_iterator it = balloons.begin();
+       it != balloons.end();
+       ++it) {
+    gfx::Point upper_left = layout_.NextPosition((*it)->GetViewSize(), &origin);
+    (*it)->SetPosition(upper_left, reposition);
+  }
+}
+
+gfx::Rect BalloonCollectionImpl::GetBalloonsBoundingBox() const {
+  // Start from the layout origin.
+  gfx::Rect bounds = gfx::Rect(layout_.GetLayoutOrigin(), gfx::Size(0, 0));
+
+  // For each balloon, extend the rectangle.  This approach is indifferent to
+  // the orientation of the balloons.
+  const Balloons& balloons = base_.balloons();
+  Balloons::const_iterator iter;
+  for (iter = balloons.begin(); iter != balloons.end(); ++iter) {
+    gfx::Rect balloon_box = gfx::Rect((*iter)->GetPosition(),
+                                      (*iter)->GetViewSize());
+    bounds = bounds.Union(balloon_box);
+  }
+
+  return bounds;
+}
+
+#if USE_OFFSETS
+void BalloonCollectionImpl::AddMessageLoopObserver() {
+  if (!added_as_message_loop_observer_) {
+    MessageLoopForUI::current()->AddObserver(this);
+    added_as_message_loop_observer_ = true;
+  }
+}
+
+void BalloonCollectionImpl::RemoveMessageLoopObserver() {
+  if (added_as_message_loop_observer_) {
+    MessageLoopForUI::current()->RemoveObserver(this);
+    added_as_message_loop_observer_ = false;
+  }
+}
+
+void BalloonCollectionImpl::CancelOffsets() {
+  reposition_factory_.RevokeAll();
+
+  // Unhook from listening to all UI events.
+  RemoveMessageLoopObserver();
+
+  const Balloons& balloons = base_.balloons();
+  for (Balloons::const_iterator it = balloons.begin();
+       it != balloons.end();
+       ++it)
+    (*it)->set_offset(gfx::Point(0, 0));
+
+  PositionBalloons(true);
+}
+
+void BalloonCollectionImpl::HandleMouseMoveEvent() {
+  if (!IsCursorInBalloonCollection()) {
+    // Mouse has left the region.  Schedule a reposition after
+    // a short delay.
+    if (reposition_factory_.empty()) {
+      MessageLoop::current()->PostDelayedTask(
+          FROM_HERE,
+          reposition_factory_.NewRunnableMethod(
+              &BalloonCollectionImpl::CancelOffsets),
+          kRepositionDelay);
+    }
+  } else {
+    // Mouse moved back into the region.  Cancel the reposition.
+    reposition_factory_.RevokeAll();
+  }
+}
+#endif
+
+BalloonCollectionImpl::Layout::Layout() {
+  RefreshSystemMetrics();
+}
+
+void BalloonCollectionImpl::Layout::GetMaxLinearSize(int* max_balloon_size,
+                                                     int* total_size) const {
+  DCHECK(max_balloon_size && total_size);
+
+  // All placement schemes are vertical, so we only care about height.
+  *total_size = work_area_.height();
+  *max_balloon_size = max_balloon_height();
+}
+
+gfx::Point BalloonCollectionImpl::Layout::GetLayoutOrigin() const {
+  int x = 0;
+  int y = 0;
+  switch (placement_) {
+    case VERTICALLY_FROM_TOP_LEFT:
+      x = work_area_.x() + HorizontalEdgeMargin();
+      y = work_area_.y() + VerticalEdgeMargin();
+      break;
+    case VERTICALLY_FROM_TOP_RIGHT:
+      x = work_area_.right() - HorizontalEdgeMargin();
+      y = work_area_.y() + VerticalEdgeMargin();
+      break;
+    case VERTICALLY_FROM_BOTTOM_LEFT:
+      x = work_area_.x() + HorizontalEdgeMargin();
+      y = work_area_.bottom() - VerticalEdgeMargin();
+      break;
+    case VERTICALLY_FROM_BOTTOM_RIGHT:
+      x = work_area_.right() - HorizontalEdgeMargin();
+      y = work_area_.bottom() - VerticalEdgeMargin();
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+  return gfx::Point(x, y);
+}
+
+gfx::Point BalloonCollectionImpl::Layout::NextPosition(
+    const gfx::Size& balloon_size,
+    gfx::Point* position_iterator) const {
+  DCHECK(position_iterator);
+
+  int x = 0;
+  int y = 0;
+  switch (placement_) {
+    case VERTICALLY_FROM_TOP_LEFT:
+      x = position_iterator->x();
+      y = position_iterator->y();
+      position_iterator->set_y(position_iterator->y() + balloon_size.height() +
+                               InterBalloonMargin());
+      break;
+    case VERTICALLY_FROM_TOP_RIGHT:
+      x = position_iterator->x() - balloon_size.width();
+      y = position_iterator->y();
+      position_iterator->set_y(position_iterator->y() + balloon_size.height() +
+                               InterBalloonMargin());
+      break;
+    case VERTICALLY_FROM_BOTTOM_LEFT:
+      position_iterator->set_y(position_iterator->y() - balloon_size.height() -
+                               InterBalloonMargin());
+      x = position_iterator->x();
+      y = position_iterator->y();
+      break;
+    case VERTICALLY_FROM_BOTTOM_RIGHT:
+      position_iterator->set_y(position_iterator->y() - balloon_size.height() -
+                               InterBalloonMargin());
+      x = position_iterator->x() - balloon_size.width();
+      y = position_iterator->y();
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+  return gfx::Point(x, y);
+}
+
+gfx::Point BalloonCollectionImpl::Layout::OffScreenLocation() const {
+  int x = 0;
+  int y = 0;
+  switch (placement_) {
+    case VERTICALLY_FROM_TOP_LEFT:
+      x = work_area_.x() + HorizontalEdgeMargin();
+      y = work_area_.y() + kBalloonMaxHeight + VerticalEdgeMargin();
+      break;
+    case VERTICALLY_FROM_TOP_RIGHT:
+      x = work_area_.right() - kBalloonMaxWidth - HorizontalEdgeMargin();
+      y = work_area_.y() + kBalloonMaxHeight + VerticalEdgeMargin();
+      break;
+    case VERTICALLY_FROM_BOTTOM_LEFT:
+      x = work_area_.x() + HorizontalEdgeMargin();
+      y = work_area_.bottom() + kBalloonMaxHeight + VerticalEdgeMargin();
+      break;
+    case VERTICALLY_FROM_BOTTOM_RIGHT:
+      x = work_area_.right() - kBalloonMaxWidth - HorizontalEdgeMargin();
+      y = work_area_.bottom() + kBalloonMaxHeight + VerticalEdgeMargin();
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+  return gfx::Point(x, y);
+}
+
+bool BalloonCollectionImpl::Layout::RequiresOffsets() const {
+  // Layout schemes that grow up from the bottom require offsets;
+  // schemes that grow down do not require offsets.
+  bool offsets = (placement_ == VERTICALLY_FROM_BOTTOM_LEFT ||
+                  placement_ == VERTICALLY_FROM_BOTTOM_RIGHT);
+
+#if defined(OS_MACOSX)
+  // These schemes are in screen-coordinates, and top and bottom
+  // are inverted on Mac.
+  offsets = !offsets;
+#endif
+
+  return offsets;
+}
+
+// static
+gfx::Size BalloonCollectionImpl::Layout::ConstrainToSizeLimits(
+    const gfx::Size& size) {
+  // restrict to the min & max sizes
+  return gfx::Size(
+      std::max(min_balloon_width(),
+               std::min(max_balloon_width(), size.width())),
+      std::max(min_balloon_height(),
+               std::min(max_balloon_height(), size.height())));
+}
+
+bool BalloonCollectionImpl::Layout::RefreshSystemMetrics() {
+  bool changed = false;
+
+#if defined(OS_MACOSX)
+  gfx::Rect new_work_area = GetMacWorkArea();
+#else
+  scoped_ptr<WindowSizer::MonitorInfoProvider> info_provider(
+      WindowSizer::CreateDefaultMonitorInfoProvider());
+  gfx::Rect new_work_area = info_provider->GetPrimaryMonitorWorkArea();
+#endif
+  if (!work_area_.Equals(new_work_area)) {
+    work_area_.SetRect(new_work_area.x(), new_work_area.y(),
+                       new_work_area.width(), new_work_area.height());
+    changed = true;
+  }
+
+  return changed;
+}