text: /*
   * (C) 1999 Lars Knoll (knoll@kde.org)
   * (C) 2000 Dirk Mueller (mueller@kde.org)
   * Copyright (C) 2004-2009, 2013 Apple 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.
   *
   */
  
  #ifndef WEEX_UIKIT_CORE_RENDERING_RENDERTEXT_H_
  #define WEEX_UIKIT_CORE_RENDERING_RENDERTEXT_H_
  
  #include <vector>
  
  #include "render/core/rendering/RenderObject.h"
  #include "render/platform/LengthFunctions.h"
  #include "render/platform/text/TextPath.h"
  #include "render/wtf/Forward.h"
  #include "render/wtf/PassRefPtr.h"
  
  namespace blink {
  class InlineTextBox;
  class TextBox;
  
  class RenderText : public RenderObject {
   public:
    // FIXME: If the node argument is not a Text node or the string argument is
    // not the content of the Text node, updating text-transform property
    // doesn't re-transform the string.
    RenderText(PassRefPtr<StringImpl>);
  #if ENABLE(ASSERT)
    virtual ~RenderText();
  #endif
  
    virtual const char* renderName() const override;
  
    void extractTextBox(InlineTextBox*);
    void attachTextBox(InlineTextBox*);
    void removeTextBox(InlineTextBox*);
  
    const String& text() const { return m_text; }
    virtual unsigned textStartOffset() const { return 0; }
  
    InlineTextBox* createInlineTextBox();
    void dirtyLineBoxes(bool fullLayout);
  
    void appendAbsoluteTextBoxesForRange(std::vector<TextBox>&,
                                         unsigned startOffset = 0,
                                         unsigned endOffset = INT_MAX);
  
    virtual void absoluteQuads(Vector<FloatQuad>&) const override final;
    void absoluteQuadsForRange(Vector<FloatQuad>&,
                               unsigned startOffset = 0,
                               unsigned endOffset = INT_MAX,
                               bool useSelectionHeight = false);
  
    enum ClippingOption { NoClipping, ClipToEllipsis };
    void absoluteQuads(Vector<FloatQuad>&, ClippingOption = NoClipping) const;
  
    virtual PositionWithAffinity positionForPoint(const LayoutPoint&) override;
  
    bool is8Bit() const { return m_text.is8Bit(); }
    const LChar* characters8() const { return m_text.impl()->characters8(); }
    const UChar* characters16() const { return m_text.impl()->characters16(); }
    bool hasEmptyText() const { return m_text.isEmpty(); }
    String substring(unsigned position, unsigned length) const {
      return m_text.substring(position, length);
    }
    UChar characterAt(unsigned) const;
    UChar uncheckedCharacterAt(unsigned) const;
    UChar operator[](unsigned i) const { return uncheckedCharacterAt(i); }
    unsigned textLength() const {
      return m_text.length();
    }  // non virtual implementation of length()
    void positionLineBox(InlineBox*);
  
    virtual float width(unsigned from,
                        unsigned len,
                        const Font&,
                        float xPos,
                        TextDirection,
                        HashSet<const SimpleFontData*>* fallbackFonts = 0,
                        GlyphOverflow* = 0) const;
    virtual float width(unsigned from,
                        unsigned len,
                        float xPos,
                        TextDirection,
                        bool firstLine = false,
                        HashSet<const SimpleFontData*>* fallbackFonts = 0,
                        GlyphOverflow* = 0) const;
  
    float minLogicalWidth() const;
    float maxLogicalWidth() const;
  
    void trimmedPrefWidths(float leadWidth,
                           float& firstLineMinWidth,
                           bool& hasBreakableStart,
                           float& lastLineMinWidth,
                           bool& hasBreakableEnd,
                           bool& hasBreakableChar,
                           bool& hasBreak,
                           float& firstLineMaxWidth,
                           float& lastLineMaxWidth,
                           float& minWidth,
                           float& maxWidth,
                           bool& stripFrontSpaces,
                           TextDirection);
  
    virtual IntRect linesBoundingBox() const;
    LayoutRect linesVisualOverflowBoundingBox() const;
  
    FloatPoint firstRunOrigin() const;
    float firstRunX() const;
    float firstRunY() const;
  
    virtual void setText(PassRefPtr<StringImpl>, bool force = false);
    void setTextWithOffset(PassRefPtr<StringImpl>,
                           unsigned offset,
                           unsigned len,
                           bool force = false);
  
    virtual bool canBeSelectionLeaf() const override { return true; }
    virtual void setSelectionState(SelectionState s) override final;
    virtual LayoutRect localCaretRect(
        InlineBox*,
        int caretOffset,
        LayoutUnit* extraWidthToEndOfLine = 0) override;
  
    LayoutUnit marginLeft() const {
      return minimumValueForLength(style()->marginLeft(), 0);
    }
    LayoutUnit marginRight() const {
      return minimumValueForLength(style()->marginRight(), 0);
    }
  
    InlineTextBox* firstTextBox() const { return m_firstTextBox; }
    InlineTextBox* lastTextBox() const { return m_lastTextBox; }
  
    virtual int caretMinOffset() const override;
    virtual int caretMaxOffset() const override;
    unsigned renderedTextLength() const;
  
    virtual int previousOffset(int current) const override final;
    virtual int previousOffsetForBackwardDeletion(
        int current) const override final;
    virtual int nextOffset(int current) const override final;
  
    bool containsReversedText() const { return m_containsReversedText; }
  
    void checkConsistency() const;
  
    bool isAllCollapsibleWhitespace() const;
  
    bool canUseSimpleFontCodePath() const { return m_canUseSimpleFontCodePath; }
  
    void removeAndDestroyTextBoxes();
  
    virtual bool nodeAtPoint(const HitTestRequest& request,
                             HitTestResult& result,
                             const HitTestLocation& location,
                             const LayoutPoint& point) override final {
      return RenderObject::nodeAtPoint(request, result, location, point);
    }
  
   protected:
    virtual void willBeDestroyed() override;
  
    virtual void styleWillChange(StyleDifference,
                                 const RenderStyle&) override final {}
    virtual void styleDidChange(StyleDifference,
                                const RenderStyle* oldStyle) override;
  
    virtual void setTextInternal(PassRefPtr<StringImpl>);
    virtual UChar previousCharacter() const;
  
    InlineTextBox* createTextBox();
  
   private:
    void computePreferredLogicalWidths(float leadWidth);
    void computePreferredLogicalWidths(
        float leadWidth,
        HashSet<const SimpleFontData*>& fallbackFonts,
        GlyphOverflow&);
  
    bool computeCanUseSimpleFontCodePath() const;
  
    // Make length() private so that callers that have a RenderText*
    // will use the more efficient textLength() instead, while
    // callers with a RenderObject* can continue to use length().
    virtual unsigned length() const override final { return textLength(); }
  
    virtual void paint(PaintInfo&,
                       const LayoutPoint&,
                       Vector<RenderBox*>& layers) override final {
      ASSERT_NOT_REACHED();
    }
    virtual void layout() override final { ASSERT_NOT_REACHED(); }
  
  
    void deleteTextBoxes();
    bool containsOnlyWhitespace(unsigned from, unsigned len) const;
    float widthFromCache(const Font&,
                         int start,
                         int len,
                         float xPos,
                         TextDirection,
                         HashSet<const SimpleFontData*>* fallbackFonts,
                         GlyphOverflow*) const;
    bool isAllASCII() const { return m_isAllASCII; }
  
    bool isText() const =
        delete;  // This will catch anyone doing an unnecessary check.
  
    // We put the bitfield first to minimize padding on 64-bit.
    bool m_hasBreakableChar : 1;  // Whether or not we can be broken into multiple
                                  // lines.
    bool m_hasBreak : 1;  // Whether or not we have a hard break (e.g., <pre> with
                          // '\n').
    bool m_hasTab : 1;    // Whether or not we have a variable width tab character
                          // (e.g., <pre> with '\t').
    bool m_hasBreakableStart : 1;
    bool m_hasBreakableEnd : 1;
    bool m_hasEndWhiteSpace : 1;
    bool m_linesDirty : 1;  // This bit indicates that the text run has already
                            // dirtied specific line boxes, and this hint will
                            // enable RenderParagraph::layoutChildren to avoid
                            // just dirtying everything when character data is
                            // modified (e.g., appended/inserted or removed).
    bool m_containsReversedText : 1;
    bool m_isAllASCII : 1;
    bool m_canUseSimpleFontCodePath : 1;
    mutable bool m_knownToHaveNoOverflowAndNoFallbackFonts : 1;
  
    float m_minWidth;
    float m_maxWidth;
    float m_firstLineMinWidth;
    float m_lastLineLineMinWidth;
  
    String m_text;
  
    InlineTextBox* m_firstTextBox;
    InlineTextBox* m_lastTextBox;
  };
  
  inline UChar RenderText::uncheckedCharacterAt(unsigned i) const {
    ASSERT_WITH_SECURITY_IMPLICATION(i < textLength());
    return is8Bit() ? characters8()[i] : characters16()[i];
  }
  
  inline UChar RenderText::characterAt(unsigned i) const {
    if (i >= textLength())
      return 0;
  
    return uncheckedCharacterAt(i);
  }
  
  DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderText, isText());
  
  #if !ENABLE(ASSERT)
  inline void RenderText::checkConsistency() const {}
  #endif
  
  }  // namespace blink
  
  #endif  // WEEX_UIKIT_CORE_RENDERING_RENDERTEXT_H_
  