Separate LineBreaker from RenderBlockLineLayout

Source/core/rendering/line/LineBreaker.cpp

+/*
+ * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
+ * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
+ * Copyright (C) 2010 Google Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "config.h"
+#include "core/rendering/line/LineBreaker.h"
+
+#include "core/rendering/line/BreakingContextInlineHeaders.h"
+
+namespace WebCore {
+
+void LineBreaker::skipLeadingWhitespace(InlineBidiResolver& resolver, LineInfo& lineInfo,
+    FloatingObject* lastFloatFromPreviousLine, LineWidth& width)
+{
+    while (!resolver.position().atEnd() && !requiresLineBox(resolver.position(), lineInfo, LeadingWhitespace)) {
+        RenderObject* object = resolver.position().object();
+        if (object->isOutOfFlowPositioned()) {
+            setStaticPositions(m_block, toRenderBox(object));
+            if (object->style()->isOriginalDisplayInlineType()) {
+                resolver.runs().addRun(createRun(0, 1, object, resolver));
+                lineInfo.incrementRunsFromLeadingWhitespace();
+            }
+        } else if (object->isFloating()) {
+            m_block->positionNewFloatOnLine(m_block->insertFloatingObject(toRenderBox(object)), lastFloatFromPreviousLine, lineInfo, width);
+        } else if (object->isText() && object->style()->hasTextCombine() && object->isCombineText() && !toRenderCombineText(object)->isCombined()) {
+            toRenderCombineText(object)->combineText();
+            if (toRenderCombineText(object)->isCombined())
+                continue;
+        }
+        resolver.position().increment(&resolver);
+    }
+    resolver.commitExplicitEmbedding();
+}
+
+void LineBreaker::reset()
+{
+    m_positionedObjects.clear();
+    m_hyphenated = false;
+    m_clear = CNONE;
+}
+
+InlineIterator LineBreaker::nextLineBreak(InlineBidiResolver& resolver, LineInfo& lineInfo, RenderTextInfo& renderTextInfo, FloatingObject* lastFloatFromPreviousLine, unsigned consecutiveHyphenatedLines, WordMeasurements& wordMeasurements)
+{
+    ShapeInsideInfo* shapeInsideInfo = m_block->layoutShapeInsideInfo();
+
+    if (!shapeInsideInfo || !shapeInsideInfo->lineOverlapsShapeBounds())
+        return nextSegmentBreak(resolver, lineInfo, renderTextInfo, lastFloatFromPreviousLine, consecutiveHyphenatedLines, wordMeasurements);
+
+    InlineIterator end = resolver.position();
+    InlineIterator oldEnd = end;
+
+    if (!shapeInsideInfo->hasSegments()) {
+        end = nextSegmentBreak(resolver, lineInfo, renderTextInfo, lastFloatFromPreviousLine, consecutiveHyphenatedLines, wordMeasurements);
+        resolver.setPositionIgnoringNestedIsolates(oldEnd);
+        return oldEnd;
+    }
+
+    const SegmentList& segments = shapeInsideInfo->segments();
+    SegmentRangeList& segmentRanges = shapeInsideInfo->segmentRanges();
+
+    for (unsigned i = 0; i < segments.size() && !end.atEnd(); i++) {
+        const InlineIterator segmentStart = resolver.position();
+        end = nextSegmentBreak(resolver, lineInfo, renderTextInfo, lastFloatFromPreviousLine, consecutiveHyphenatedLines, wordMeasurements);
+
+        ASSERT(segmentRanges.size() == i);
+        if (resolver.position().atEnd()) {
+            segmentRanges.append(LineSegmentRange(segmentStart, end));
+            break;
+        }
+        if (resolver.position() == end) {
+            // Nothing fit this segment
+            end = segmentStart;
+            segmentRanges.append(LineSegmentRange(segmentStart, segmentStart));
+            resolver.setPositionIgnoringNestedIsolates(segmentStart);
+        } else {
+            // Note that resolver.position is already skipping some of the white space at the beginning of the line,
+            // so that's why segmentStart might be different than resolver.position().
+            LineSegmentRange range(resolver.position(), end);
+            segmentRanges.append(range);
+            resolver.setPosition(end, numberOfIsolateAncestors(end));
+
+            if (lineInfo.previousLineBrokeCleanly()) {
+                // If we hit a new line break, just stop adding anything to this line.
+                break;
+            }
+        }
+    }
+    resolver.setPositionIgnoringNestedIsolates(oldEnd);
+    return end;
+}
+
+InlineIterator LineBreaker::nextSegmentBreak(InlineBidiResolver& resolver, LineInfo& lineInfo, RenderTextInfo& renderTextInfo, FloatingObject* lastFloatFromPreviousLine, unsigned consecutiveHyphenatedLines, WordMeasurements& wordMeasurements)
+{
+    reset();
+
+    ASSERT(resolver.position().root() == m_block);
+
+    bool appliedStartWidth = resolver.position().offset() > 0;
+
+    LineWidth width(*m_block, lineInfo.isFirstLine(), requiresIndent(lineInfo.isFirstLine(), lineInfo.previousLineBrokeCleanly(), m_block->style()));
+
+    skipLeadingWhitespace(resolver, lineInfo, lastFloatFromPreviousLine, width);
+
+    if (resolver.position().atEnd())
+        return resolver.position();
+
+    BreakingContext context(resolver, lineInfo, width, renderTextInfo, lastFloatFromPreviousLine, appliedStartWidth, m_block);
+
+    while (context.currentObject()) {
+        context.initializeForCurrentObject();
+        if (context.currentObject()->isBR()) {
+            context.handleBR(m_clear);
+        } else if (context.currentObject()->isOutOfFlowPositioned()) {
+            context.handleOutOfFlowPositioned(m_positionedObjects);
+        } else if (context.currentObject()->isFloating()) {
+            context.handleFloat();
+        } else if (context.currentObject()->isRenderInline()) {
+            context.handleEmptyInline();
+        } else if (context.currentObject()->isReplaced()) {
+            context.handleReplaced();
+        } else if (context.currentObject()->isText()) {
+            if (context.handleText(wordMeasurements, m_hyphenated)) {
+                // We've hit a hard text line break. Our line break iterator is updated, so go ahead and early return.
+                return context.lineBreak();
+            }
+        } else {
+            ASSERT_NOT_REACHED();
+        }
+
+        if (context.atEnd())
+            return context.handleEndOfLine();
+
+        context.commitAndUpdateLineBreakIfNeeded();
+
+        if (context.atEnd())
+            return context.handleEndOfLine();
+
+        context.increment();
+    }
+
+    context.clearLineBreakIfFitsOnLine();
+
+    return context.handleEndOfLine();
+}
+
+}