Move line-specific code into LayoutBlockFlow::positionForPoint().

third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/layout/LayoutBlockFlow.h"
 
 #include "core/dom/AXObjectCache.h"
+#include "core/editing/Editor.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLDialogElement.h"
 #include "core/layout/HitTestLocation.h"
 #include "core/layout/LayoutAnalyzer.h"
 #include "core/layout/LayoutFlowThread.h"
 #include "core/layout/LayoutMultiColumnFlowThread.h"
 #include "core/layout/LayoutMultiColumnSpannerPlaceholder.h"
 #include "core/layout/LayoutPagedFlowThread.h"
@@ skipping 3129 matching lines @@
 
     // FIXME: Glyph overflow will get lost in this case, but not really a big deal.
     GlyphOverflowAndFallbackFontsMap textBoxDataMap;
     for (ListHashSet<RootInlineBox*>::const_iterator it = lineBoxes.begin(); it != lineBoxes.end(); ++it) {
         RootInlineBox* box = *it;
         box->computeOverflow(box->lineTop(), box->lineBottom(), textBoxDataMap);
     }
     return childrenOverflowChanged;
 }
 
+PositionWithAffinity LayoutBlockFlow::positionForPoint(const LayoutPoint& point)
+{
+    if (isAtomicInlineLevel()) {
+        PositionWithAffinity position = positionForPointIfOutsideAtomicInlineLevel(point);
+        if (!position.isNull())
+            return position;
+    }
+    if (!childrenInline())
+        return LayoutBlock::positionForPoint(point);
+
+    LayoutPoint pointInContents = point;
+    offsetForContents(pointInContents);
+    LayoutPoint pointInLogicalContents(pointInContents);
+    if (!isHorizontalWritingMode())
+        pointInLogicalContents = pointInLogicalContents.transposedPoint();
+
+    if (!firstRootBox())
+        return createPositionWithAffinity(0);
+
+    bool linesAreFlipped = style()->isFlippedLinesWritingMode();
+    bool blocksAreFlipped = style()->isFlippedBlocksWritingMode();
+
+    // look for the closest line box in the root box which is at the passed-in y coordinate
+    InlineBox* closestBox = nullptr;
+    RootInlineBox* firstRootBoxWithChildren = nullptr;
+    RootInlineBox* lastRootBoxWithChildren = nullptr;
+    for (RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox()) {
+        if (!root->firstLeafChild())
+            continue;
+        if (!firstRootBoxWithChildren)
+            firstRootBoxWithChildren = root;
+
+        if (!linesAreFlipped && root->isFirstAfterPageBreak() && (pointInLogicalContents.y() < root->lineTopWithLeading()
+            || (blocksAreFlipped && pointInLogicalContents.y() == root->lineTopWithLeading())))
+            break;
+
+        lastRootBoxWithChildren = root;
+
+        // check if this root line box is located at this y coordinate
+        if (pointInLogicalContents.y() < root->selectionBottom() || (blocksAreFlipped && pointInLogicalContents.y() == root->selectionBottom())) {
+            if (linesAreFlipped) {
+                RootInlineBox* nextRootBoxWithChildren = root->nextRootBox();
+                while (nextRootBoxWithChildren && !nextRootBoxWithChildren->firstLeafChild())
+                    nextRootBoxWithChildren = nextRootBoxWithChildren->nextRootBox();
+
+                if (nextRootBoxWithChildren && nextRootBoxWithChildren->isFirstAfterPageBreak() && (pointInLogicalContents.y() > nextRootBoxWithChildren->lineTopWithLeading()
+                    || (!blocksAreFlipped && pointInLogicalContents.y() == nextRootBoxWithChildren->lineTopWithLeading())))
+                    continue;
+            }
+            closestBox = root->closestLeafChildForLogicalLeftPosition(pointInLogicalContents.x());
+            if (closestBox)
+                break;
+        }
+    }
+
+    bool moveCaretToBoundary = document().frame()->editor().behavior().shouldMoveCaretToHorizontalBoundaryWhenPastTopOrBottom();
+
+    if (!moveCaretToBoundary && !closestBox && lastRootBoxWithChildren) {
+        // y coordinate is below last root line box, pretend we hit it
+        closestBox = lastRootBoxWithChildren->closestLeafChildForLogicalLeftPosition(pointInLogicalContents.x());
+    }
+
+    if (closestBox) {
+        if (moveCaretToBoundary) {
+            LayoutUnit firstRootBoxWithChildrenTop = std::min<LayoutUnit>(firstRootBoxWithChildren->selectionTop(), firstRootBoxWithChildren->logicalTop());
+            if (pointInLogicalContents.y() < firstRootBoxWithChildrenTop
+                || (blocksAreFlipped && pointInLogicalContents.y() == firstRootBoxWithChildrenTop)) {
+                InlineBox* box = firstRootBoxWithChildren->firstLeafChild();
+                if (box->isLineBreak()) {
+                    if (InlineBox* newBox = box->nextLeafChildIgnoringLineBreak())
+                        box = newBox;
+                }
+                // y coordinate is above first root line box, so return the start of the first
+                return PositionWithAffinity(positionForBox(box, true));
+            }
+        }
+
+        // pass the box a top position that is inside it
+        LayoutPoint point(pointInLogicalContents.x(), closestBox->root().blockDirectionPointInLine());
+        if (!isHorizontalWritingMode())
+            point = point.transposedPoint();
+        if (closestBox->getLineLayoutItem().isAtomicInlineLevel())
+            return positionForPointRespectingEditingBoundaries(LineLayoutBox(closestBox->getLineLayoutItem()), point);
+        return closestBox->getLineLayoutItem().positionForPoint(point);
+    }
+
+    if (lastRootBoxWithChildren) {
+        // We hit this case for Mac behavior when the Y coordinate is below the last box.
+        ASSERT(moveCaretToBoundary);
+        InlineBox* logicallyLastBox;
+        if (lastRootBoxWithChildren->getLogicalEndBoxWithNode(logicallyLastBox))
+            return PositionWithAffinity(positionForBox(logicallyLastBox, false));
+    }
+
+    // Can't reach this. We have a root line box, but it has no kids.
+    // FIXME: This should ASSERT_NOT_REACHED(), but clicking on placeholder text
+    // seems to hit this code path.
+    return createPositionWithAffinity(0);
+}
+
 #ifndef NDEBUG
 
 void LayoutBlockFlow::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const LayoutObject* obj) const
 {
     showLayoutObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace blink