Move LayouetSelection function definition from layout/LayoutView.cpp to editing/LayoutSelection.cpp

third_party/WebKit/Source/core/editing/LayoutSelection.cpp

Index: third_party/WebKit/Source/core/editing/LayoutSelection.cpp
diff --git a/third_party/WebKit/Source/core/editing/LayoutSelection.cpp b/third_party/WebKit/Source/core/editing/LayoutSelection.cpp
index 540146afea59317b2f41c95f2de8b3f74415c3f7..1dccdebda0a3ee1b88a8e1343b95427310c1fd8c 100644
--- a/third_party/WebKit/Source/core/editing/LayoutSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/LayoutSelection.cpp
@@ -28,6 +28,7 @@
 #include "core/editing/VisibleUnits.h"
 #include "core/html/TextControlElement.h"
 #include "core/layout/LayoutView.h"
+#include "core/paint/PaintLayer.h"
 
 namespace blink {
 
@@ -111,6 +112,231 @@ SelectionInFlatTree LayoutSelection::CalcVisibleSelection(
   return builder.Build();
 }
 
+static LayoutObject* LayoutObjectAfterPosition(LayoutObject* object,
+                                               unsigned offset) {
+  if (!object)
+    return nullptr;
+
+  LayoutObject* child = object->ChildAt(offset);
+  return child ? child : object->NextInPreOrderAfterChildren();
+}
+
+// When exploring the LayoutTree looking for the nodes involved in the
+// Selection, sometimes it's required to change the traversing direction because
+// the "start" position is below the "end" one.
+static inline LayoutObject* GetNextOrPrevLayoutObjectBasedOnDirection(
+    const LayoutObject* o,
+    const LayoutObject* stop,
+    bool& continue_exploring,
+    bool& exploring_backwards) {
+  LayoutObject* next;
+  if (exploring_backwards) {
+    next = o->PreviousInPreOrder();
+    continue_exploring = next && !(next)->IsLayoutView();
+  } else {
+    next = o->NextInPreOrder();
+    continue_exploring = next && next != stop;
+    exploring_backwards = !next && (next != stop);
+    if (exploring_backwards) {
+      next = stop->PreviousInPreOrder();
+      continue_exploring = next && !next->IsLayoutView();
+    }
+  }
+
+  return next;
+}
+
+void LayoutSelection::SetSelection(
+    LayoutObject* start,
+    int start_pos,
+    LayoutObject* end,
+    int end_pos,
+    SelectionPaintInvalidationMode block_paint_invalidation_mode) {
+  // This code makes no assumptions as to if the layout tree is up to date or
+  // not and will not try to update it. Currently clearSelection calls this
+  // (intentionally) without updating the layout tree as it doesn't care.
+  // Other callers may want to force recalc style before calling this.
+
+  // Make sure both our start and end objects are defined.
+  // Check www.msnbc.com and try clicking around to find the case where this
+  // happened.
+  if ((start && !end) || (end && !start))
+    return;
+
+  // Just return if the selection hasn't changed.
+  if (selection_start_ == start && selection_start_pos_ == start_pos &&
+      selection_end_ == end && selection_end_pos_ == end_pos)
+    return;
+
+  // Record the old selected objects. These will be used later when we compare
+  // against the new selected objects.
+  int old_start_pos = selection_start_pos_;
+  int old_end_pos = selection_end_pos_;
+
+  // Objects each have a single selection rect to examine.
+  typedef HashMap<LayoutObject*, SelectionState> SelectedObjectMap;
+  SelectedObjectMap old_selected_objects;
+  // FIXME: |newSelectedObjects| doesn't really need to store the
+  // SelectionState, it's just more convenient to have it use the same data
+  // structure as |oldSelectedObjects|.
+  SelectedObjectMap new_selected_objects;
+
+  // Blocks contain selected objects and fill gaps between them, either on the
+  // left, right, or in between lines and blocks.
+  // In order to get the visual rect right, we have to examine left, middle, and
+  // right rects individually, since otherwise the union of those rects might
+  // remain the same even when changes have occurred.
+  typedef HashMap<LayoutBlock*, SelectionState> SelectedBlockMap;
+  SelectedBlockMap old_selected_blocks;
+  // FIXME: |newSelectedBlocks| doesn't really need to store the SelectionState,
+  // it's just more convenient to have it use the same data structure as
+  // |oldSelectedBlocks|.
+  SelectedBlockMap new_selected_blocks;
+
+  LayoutObject* os = selection_start_;
+  LayoutObject* stop =
+      LayoutObjectAfterPosition(selection_end_, selection_end_pos_);
+  bool exploring_backwards = false;
+  bool continue_exploring = os && (os != stop);
+  while (continue_exploring) {
+    if ((os->CanBeSelectionLeaf() || os == selection_start_ ||
+         os == selection_end_) &&
+        os->GetSelectionState() != SelectionNone) {
+      // Blocks are responsible for painting line gaps and margin gaps.  They
+      // must be examined as well.
+      old_selected_objects.Set(os, os->GetSelectionState());
+      if (block_paint_invalidation_mode == kPaintInvalidationNewXOROld) {
+        LayoutBlock* cb = os->ContainingBlock();
+        while (cb && !cb->IsLayoutView()) {
+          SelectedBlockMap::AddResult result =
+              old_selected_blocks.insert(cb, cb->GetSelectionState());
+          if (!result.is_new_entry)
+            break;
+          cb = cb->ContainingBlock();
+        }
+      }
+    }
+
+    os = GetNextOrPrevLayoutObjectBasedOnDirection(os, stop, continue_exploring,
+                                                   exploring_backwards);
+  }
+
+  // Now clear the selection.
+  SelectedObjectMap::iterator old_objects_end = old_selected_objects.end();
+  for (SelectedObjectMap::iterator i = old_selected_objects.begin();
+       i != old_objects_end; ++i)
+    i->key->SetSelectionStateIfNeeded(SelectionNone);
+
+  // set selection start and end
+  selection_start_ = start;
+  selection_start_pos_ = start_pos;
+  selection_end_ = end;
+  selection_end_pos_ = end_pos;
+
+  // Update the selection status of all objects between m_selectionStart and
+  // m_selectionEnd
+  if (start && start == end) {
+    start->SetSelectionStateIfNeeded(SelectionBoth);
+  } else {
+    if (start)
+      start->SetSelectionStateIfNeeded(SelectionStart);
+    if (end)
+      end->SetSelectionStateIfNeeded(SelectionEnd);
+  }
+
+  LayoutObject* o = start;
+  stop = LayoutObjectAfterPosition(end, end_pos);
+
+  while (o && o != stop) {
+    if (o != start && o != end && o->CanBeSelectionLeaf())
+      o->SetSelectionStateIfNeeded(SelectionInside);
+    o = o->NextInPreOrder();
+  }
+
+  // Now that the selection state has been updated for the new objects, walk
+  // them again and put them in the new objects list.
+  o = start;
+  exploring_backwards = false;
+  continue_exploring = o && (o != stop);
+  while (continue_exploring) {
+    if ((o->CanBeSelectionLeaf() || o == start || o == end) &&
+        o->GetSelectionState() != SelectionNone) {
+      new_selected_objects.Set(o, o->GetSelectionState());
+      LayoutBlock* cb = o->ContainingBlock();
+      while (cb && !cb->IsLayoutView()) {
+        SelectedBlockMap::AddResult result =
+            new_selected_blocks.insert(cb, cb->GetSelectionState());
+        if (!result.is_new_entry)
+          break;
+        cb = cb->ContainingBlock();
+      }
+    }
+
+    o = GetNextOrPrevLayoutObjectBasedOnDirection(o, stop, continue_exploring,
+                                                  exploring_backwards);
+  }
+
+  // TODO(yoichio): DCHECK(frame_selection_->,,,->GetFrameView());
+  if (!frame_selection_->GetDocument().GetLayoutView()->GetFrameView())
+    return;
+
+  // Have any of the old selected objects changed compared to the new selection?
+  for (SelectedObjectMap::iterator i = old_selected_objects.begin();
+       i != old_objects_end; ++i) {
+    LayoutObject* obj = i->key;
+    SelectionState new_selection_state = obj->GetSelectionState();
+    SelectionState old_selection_state = i->value;
+    if (new_selection_state != old_selection_state ||
+        (selection_start_ == obj && old_start_pos != selection_start_pos_) ||
+        (selection_end_ == obj && old_end_pos != selection_end_pos_)) {
+      obj->SetShouldInvalidateSelection();
+      new_selected_objects.erase(obj);
+    }
+  }
+
+  // Any new objects that remain were not found in the old objects dict, and so
+  // they need to be updated.
+  SelectedObjectMap::iterator new_objects_end = new_selected_objects.end();
+  for (SelectedObjectMap::iterator i = new_selected_objects.begin();
+       i != new_objects_end; ++i)
+    i->key->SetShouldInvalidateSelection();
+
+  // Have any of the old blocks changed?
+  SelectedBlockMap::iterator old_blocks_end = old_selected_blocks.end();
+  for (SelectedBlockMap::iterator i = old_selected_blocks.begin();
+       i != old_blocks_end; ++i) {
+    LayoutBlock* block = i->key;
+    SelectionState new_selection_state = block->GetSelectionState();
+    SelectionState old_selection_state = i->value;
+    if (new_selection_state != old_selection_state) {
+      block->SetShouldInvalidateSelection();
+      new_selected_blocks.erase(block);
+    }
+  }
+
+  // Any new blocks that remain were not found in the old blocks dict, and so
+  // they need to be updated.
+  SelectedBlockMap::iterator new_blocks_end = new_selected_blocks.end();
+  for (SelectedBlockMap::iterator i = new_selected_blocks.begin();
+       i != new_blocks_end; ++i)
+    i->key->SetShouldInvalidateSelection();
+}
+
+void LayoutSelection::SelectionStartEnd(int& start_pos, int& end_pos) {
+  Commit(*frame_selection_->GetDocument().GetLayoutView());
+  start_pos = selection_start_pos_;
+  end_pos = selection_end_pos_;
+}
+
+void LayoutSelection::ClearSelection() {
+  // For querying Layer::compositingState()
+  // This is correct, since destroying layout objects needs to cause eager paint
+  // invalidations.
+  DisableCompositingQueryAsserts disabler;
+
+  SetSelection(0, -1, 0, -1, kPaintInvalidationNewMinusOld);
+}
+
 void LayoutSelection::Commit(LayoutView& layout_view) {
   if (!HasPendingSelection())
     return;
@@ -176,6 +402,66 @@ void LayoutSelection::OnDocumentShutdown() {
   selection_end_pos_ = -1;
 }
 
+static LayoutRect SelectionRectForLayoutObject(const LayoutObject* object) {
+  if (!object->IsRooted())
+    return LayoutRect();
+
+  if (!object->CanUpdateSelectionOnRootLineBoxes())
+    return LayoutRect();
+
+  return object->SelectionRectInViewCoordinates();
+}
+
+IntRect LayoutSelection::SelectionBounds() {
+  // Now create a single bounding box rect that encloses the whole selection.
+  LayoutRect sel_rect;
+
+  typedef HashSet<const LayoutBlock*> VisitedContainingBlockSet;
+  VisitedContainingBlockSet visited_containing_blocks;
+
+  Commit(*frame_selection_->GetDocument().GetLayoutView());
+  LayoutObject* os = selection_start_;
+  LayoutObject* stop =
+      LayoutObjectAfterPosition(selection_end_, selection_end_pos_);
+  while (os && os != stop) {
+    if ((os->CanBeSelectionLeaf() || os == selection_start_ ||
+         os == selection_end_) &&
+        os->GetSelectionState() != SelectionNone) {
+      // Blocks are responsible for painting line gaps and margin gaps. They
+      // must be examined as well.
+      sel_rect.Unite(SelectionRectForLayoutObject(os));
+      const LayoutBlock* cb = os->ContainingBlock();
+      while (cb && !cb->IsLayoutView()) {
+        sel_rect.Unite(SelectionRectForLayoutObject(cb));
+        VisitedContainingBlockSet::AddResult add_result =
+            visited_containing_blocks.insert(cb);
+        if (!add_result.is_new_entry)
+          break;
+        cb = cb->ContainingBlock();
+      }
+    }
+
+    os = os->NextInPreOrder();
+  }
+
+  return PixelSnappedIntRect(sel_rect);
+}
+
+void LayoutSelection::InvalidatePaintForSelection() {
+  LayoutObject* end =
+      LayoutObjectAfterPosition(selection_end_, selection_end_pos_);
+  for (LayoutObject* o = selection_start_; o && o != end;
+       o = o->NextInPreOrder()) {
+    if (!o->CanBeSelectionLeaf() && o != selection_start_ &&
+        o != selection_end_)
+      continue;
+    if (o->GetSelectionState() == SelectionNone)
+      continue;
+
+    o->SetShouldInvalidateSelection();
+  }
+}
+
 DEFINE_TRACE(LayoutSelection) {
   visitor->Trace(frame_selection_);
 }