/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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#ifndef INCLUDED_VCL_INC_SALLAYOUT_HXX
#define INCLUDED_VCL_INC_SALLAYOUT_HXX

#include <iostream>

#include <tools/gen.hxx>
#include <basegfx/polygon/b2dpolypolygon.hxx>
#include <i18nlangtag/languagetag.hxx>

#ifndef _TOOLS_LANG_HXX
typedef unsigned short LanguageType;
#endif

#include <vector>
#include <list>
#include <vcl/dllapi.h>

// for typedef sal_UCS4
#include <vcl/vclenum.hxx>
#include "salglyphid.hxx"

class SalGraphics;
class PhysicalFontFace;

#define MAX_FALLBACK 16

// Layout options
#define SAL_LAYOUT_BIDI_RTL                 0x0001
#define SAL_LAYOUT_BIDI_STRONG              0x0002
#define SAL_LAYOUT_RIGHT_ALIGN              0x0004
#define SAL_LAYOUT_KERNING_PAIRS            0x0010
#define SAL_LAYOUT_KERNING_ASIAN            0x0020
#define SAL_LAYOUT_VERTICAL                 0x0040
#define SAL_LAYOUT_COMPLEX_DISABLED         0x0100
#define SAL_LAYOUT_ENABLE_LIGATURES         0x0200
#define SAL_LAYOUT_SUBSTITUTE_DIGITS        0x0400
#define SAL_LAYOUT_KASHIDA_JUSTIFICATON     0x0800
#define SAL_LAYOUT_DISABLE_GLYPH_PROCESSING 0x1000
#define SAL_LAYOUT_FOR_FALLBACK             0x2000

// used for managing runs e.g. for BiDi, glyph and script fallback
class VCL_PLUGIN_PUBLIC ImplLayoutRuns
{
private:
    int                 mnRunIndex;
    std::vector<int>    maRuns;

public:
            ImplLayoutRuns() { mnRunIndex = 0; maRuns.reserve(8); }

    void    Clear()             { maRuns.clear(); }
    bool    AddPos( int nCharPos, bool bRTL );
    bool    AddRun( int nMinRunPos, int nEndRunPos, bool bRTL );

    bool    IsEmpty() const     { return maRuns.empty(); }
    void    ResetPos()          { mnRunIndex = 0; }
    void    NextRun()           { mnRunIndex += 2; }
    bool    GetRun( int* nMinRunPos, int* nEndRunPos, bool* bRTL ) const;
    bool    GetNextPos( int* nCharPos, bool* bRTL );
    bool    PosIsInRun( int nCharPos ) const;
    bool    PosIsInAnyRun( int nCharPos ) const;
};


class ImplLayoutArgs
{
public:
    // string related inputs
    LanguageTag         maLanguageTag;
    int                 mnFlags;
    int                 mnLength;
    int                 mnMinCharPos;
    int                 mnEndCharPos;
    const sal_Unicode*  mpStr;

    // positioning related inputs
    const sal_Int32*    mpDXArray;          // in pixel units
    long                mnLayoutWidth;      // in pixel units
    int                 mnOrientation;      // in 0-3600 system

    // data for bidi and glyph+script fallback
    ImplLayoutRuns      maRuns;
    ImplLayoutRuns      maFallbackRuns;

public:
                ImplLayoutArgs( const sal_Unicode* pStr, int nLength,
                    int nMinCharPos, int nEndCharPos, int nFlags, const LanguageTag& rLanguageTag );

    void        SetLayoutWidth( long nWidth )       { mnLayoutWidth = nWidth; }
    void        SetDXArray( const sal_Int32* pDXArray )  { mpDXArray = pDXArray; }
    void        SetOrientation( int nOrientation )  { mnOrientation = nOrientation; }

    void        ResetPos()
                    { maRuns.ResetPos(); }
    bool        GetNextPos( int* nCharPos, bool* bRTL )
                    { return maRuns.GetNextPos( nCharPos, bRTL ); }
    bool        GetNextRun( int* nMinRunPos, int* nEndRunPos, bool* bRTL );
    bool        NeedFallback( int nCharPos, bool bRTL )
                    { return maFallbackRuns.AddPos( nCharPos, bRTL ); }
    bool        NeedFallback( int nMinRunPos, int nEndRunPos, bool bRTL )
                    { return maFallbackRuns.AddRun( nMinRunPos, nEndRunPos, bRTL ); }
    // methods used by BiDi and glyph fallback
    bool        NeedFallback() const
                    { return !maFallbackRuns.IsEmpty(); }
    bool        PrepareFallback();

protected:
    void        AddRun( int nMinCharPos, int nEndCharPos, bool bRTL );
};

// For nice SAL_INFO logging of ImplLayoutArgs values
std::ostream &operator <<(std::ostream& s, ImplLayoutArgs &rArgs);

// helper functions often used with ImplLayoutArgs
bool IsDiacritic( sal_UCS4 );
int GetVerticalFlags( sal_UCS4 );
sal_UCS4 GetVerticalChar( sal_UCS4 );

// all positions/widths are in font units
// one exception: drawposition is in pixel units

// Unfortunately there is little documentation to help implementors of
// new classes derived from SalLayout ("layout engines"), and the code
// and data structures are far from obvious.

// For instance, I *think* the important virtual functions in the
// layout engines are called in this order:

// * InitFont()
// * LayoutText()
// * AdjustLayout(), any number of times (but presumably
// usually not at all or just once)
// * Optionally, DrawText()

// Functions that just return information like GetTexWidth() and
// FillDXArray() are called after LayoutText() and before DrawText().

// Another important questions is which parts of an ImplLayoutArgs can
// be changed by callers between LayoutText() and AdjustLayout()
// calls. It probably makes sense only if one assumes that the "string
// related inputs" part are not changed after LayoutText().

// But why use the same ImplLayoutArgs structure as parameter for both
// LayoutText() and AdjustLayout() in the first place? And why
// duplicate some of the fields in both SalLayout and ImplLayoutArgs
// (mnMinCharPos, mnEndCharPos, mnLayoutFlags==mnFlags,
// mnOrientation)? Lost in history...

class VCL_PLUGIN_PUBLIC SalLayout
{
public:
    // used by upper layers
    Point&          DrawBase()                              { return maDrawBase; }
    const Point&    DrawBase() const                        { return maDrawBase; }
    Point&          DrawOffset()                            { return maDrawOffset; }
    const Point&    DrawOffset() const                      { return maDrawOffset; }
    Point           GetDrawPosition( const Point& rRelative = Point(0,0) ) const;

    virtual bool    LayoutText( ImplLayoutArgs& ) = 0;  // first step of layouting
    virtual void    AdjustLayout( ImplLayoutArgs& );    // adjusting after fallback etc.
    virtual void    InitFont() const {}
    virtual void    DrawText( SalGraphics& ) const = 0;

    int             GetUnitsPerPixel() const                { return mnUnitsPerPixel; }
    int             GetOrientation() const                  { return mnOrientation; }

    // methods using string indexing
    virtual sal_Int32 GetTextBreak(long nMaxWidth, long nCharExtra=0, int nFactor=1) const = 0;
    virtual long    FillDXArray( sal_Int32* pDXArray ) const = 0;
    virtual long    GetTextWidth() const { return FillDXArray( NULL ); }
    virtual void    GetCaretPositions( int nArraySize, sal_Int32* pCaretXArray ) const = 0;
    virtual bool    IsKashidaPosValid ( int /*nCharPos*/ ) const { return true; } // i60594

    // methods using glyph indexing
    virtual int     GetNextGlyphs( int nLen, sal_GlyphId* pGlyphIdAry, Point& rPos, int&,
                        sal_Int32* pGlyphAdvAry = NULL, int* pCharPosAry = NULL,
                        const PhysicalFontFace** pFallbackFonts = NULL ) const = 0;
    virtual bool    GetOutline( SalGraphics&, ::basegfx::B2DPolyPolygonVector& ) const;
    virtual bool    GetBoundRect( SalGraphics&, Rectangle& ) const;

    virtual bool    IsSpacingGlyph( sal_GlyphId ) const;

    // reference counting
    void            Release() const;

    // used by glyph+font+script fallback
    virtual void    MoveGlyph( int nStart, long nNewXPos ) = 0;
    virtual void    DropGlyph( int nStart ) = 0;
    virtual void    Simplify( bool bIsBase ) = 0;
    virtual void    DisableGlyphInjection( bool /*bDisable*/ ) {}

protected:
    // used by layout engines
                    SalLayout();
    virtual         ~SalLayout();

    // used by layout layers
    void            SetUnitsPerPixel( int n )               { mnUnitsPerPixel = n; }
    void            SetOrientation( int nOrientation )      // in 0-3600 system
                    { mnOrientation = nOrientation; }

    static int      CalcAsianKerning( sal_UCS4, bool bLeft, bool bVertical );

private:
    // enforce proper copy semantic
    SAL_DLLPRIVATE  SalLayout( const SalLayout& );
    SAL_DLLPRIVATE  SalLayout& operator=( const SalLayout& );

protected:
    int             mnMinCharPos;
    int             mnEndCharPos;
    int             mnLayoutFlags;

    int             mnUnitsPerPixel;
    int             mnOrientation;

    mutable int     mnRefCount;
    mutable Point   maDrawOffset;
    Point           maDrawBase;
};

class VCL_PLUGIN_PUBLIC MultiSalLayout : public SalLayout
{
public:
    virtual void    DrawText( SalGraphics& ) const;
    virtual sal_Int32 GetTextBreak(long nMaxWidth, long nCharExtra, int nFactor) const SAL_OVERRIDE;
    virtual long    FillDXArray( sal_Int32* pDXArray ) const;
    virtual void    GetCaretPositions( int nArraySize, sal_Int32* pCaretXArray ) const;
    virtual int     GetNextGlyphs( int nLen, sal_GlyphId* pGlyphIdxAry, Point& rPos,
                                   int&, sal_Int32* pGlyphAdvAry, int* pCharPosAry,
                                   const PhysicalFontFace** pFallbackFonts ) const;
    virtual bool    GetOutline( SalGraphics&, ::basegfx::B2DPolyPolygonVector& ) const;

    // used only by OutputDevice::ImplLayout, TODO: make friend
    explicit        MultiSalLayout( SalLayout& rBaseLayout,
                                    const PhysicalFontFace* pBaseFont = NULL );
    virtual bool    AddFallback( SalLayout& rFallbackLayout,
                                 ImplLayoutRuns&, const PhysicalFontFace* pFallbackFont );
    virtual bool    LayoutText( ImplLayoutArgs& );
    virtual void    AdjustLayout( ImplLayoutArgs& );
    virtual void    InitFont() const;

    void SetInComplete(bool bInComplete = true);

protected:
    virtual         ~MultiSalLayout();

private:
    // dummy implementations
    virtual void    MoveGlyph( int, long ) {}
    virtual void    DropGlyph( int ) {}
    virtual void    Simplify( bool ) {}

    // enforce proper copy semantic
    SAL_DLLPRIVATE  MultiSalLayout( const MultiSalLayout& );
    SAL_DLLPRIVATE  MultiSalLayout& operator=( const MultiSalLayout& );

private:
    SalLayout*      mpLayouts[ MAX_FALLBACK ];
    const PhysicalFontFace* mpFallbackFonts[ MAX_FALLBACK ];
    ImplLayoutRuns  maFallbackRuns[ MAX_FALLBACK ];
    int             mnLevel;
    bool            mbInComplete;
};

struct GlyphItem
{
    int     mnFlags;
    int     mnCharPos;      // index in string
    int     mnOrigWidth;    // original glyph width
    int     mnNewWidth;     // width after adjustments
    int     mnXOffset;
    sal_GlyphId maGlyphId;
    Point   maLinearPos;    // absolute position of non rotated string

public:
            GlyphItem() {}

            GlyphItem( int nCharPos, sal_GlyphId aGlyphId, const Point& rLinearPos,
                long nFlags, int nOrigWidth )
            :   mnFlags(nFlags), mnCharPos(nCharPos),
                mnOrigWidth(nOrigWidth), mnNewWidth(nOrigWidth),
                mnXOffset(0),
                maGlyphId(aGlyphId), maLinearPos(rLinearPos)
            {}

            GlyphItem( int nCharPos, sal_GlyphId aGlyphId, const Point& rLinearPos,
                long nFlags, int nOrigWidth, int nXOffset )
            :   mnFlags(nFlags), mnCharPos(nCharPos),
                mnOrigWidth(nOrigWidth), mnNewWidth(nOrigWidth),
                mnXOffset(nXOffset),
                maGlyphId(aGlyphId), maLinearPos(rLinearPos)
            {}


    enum{ FALLBACK_MASK=0xFF, IS_IN_CLUSTER=0x100, IS_RTL_GLYPH=0x200, IS_DIACRITIC=0x400 };

    bool    IsClusterStart() const  { return ((mnFlags & IS_IN_CLUSTER) == 0); }
    bool    IsRTLGlyph() const      { return ((mnFlags & IS_RTL_GLYPH) != 0); }
    bool    IsDiacritic() const     { return ((mnFlags & IS_DIACRITIC) != 0); }
};

typedef std::list<GlyphItem> GlyphList;
typedef std::vector<GlyphItem> GlyphVector;

class VCL_PLUGIN_PUBLIC GenericSalLayout : public SalLayout
{
public:
    // used by layout engines
    void            AppendGlyph( const GlyphItem& );
    void            Reserve(int size) { m_GlyphItems.reserve(size + 1); }
    virtual void    AdjustLayout( ImplLayoutArgs& );
    virtual void    ApplyDXArray( ImplLayoutArgs& );
    virtual void    Justify( long nNewWidth );
    void            KashidaJustify( long nIndex, int nWidth );
    void            ApplyAsianKerning( const sal_Unicode*, int nLength );
    void            SortGlyphItems();

    // used by upper layers
    virtual long    GetTextWidth() const;
    virtual long    FillDXArray( sal_Int32* pDXArray ) const;
    virtual sal_Int32 GetTextBreak(long nMaxWidth, long nCharExtra, int nFactor) const SAL_OVERRIDE;
    virtual void    GetCaretPositions( int nArraySize, sal_Int32* pCaretXArray ) const;

    // used by display layers
    virtual int     GetNextGlyphs( int nLen, sal_GlyphId* pGlyphIdxAry, Point& rPos, int&,
                        sal_Int32* pGlyphAdvAry = NULL, int* pCharPosAry = NULL,
                        const PhysicalFontFace** pFallbackFonts = NULL ) const;

protected:
                    GenericSalLayout();
    virtual         ~GenericSalLayout();

    // for glyph+font+script fallback
    virtual void    MoveGlyph( int nStart, long nNewXPos );
    virtual void    DropGlyph( int nStart );
    virtual void    Simplify( bool bIsBase );

    bool            GetCharWidths( sal_Int32* pCharWidths ) const;

    GlyphVector     m_GlyphItems;

private:
    mutable Point   maBasePoint;

    // enforce proper copy semantic
    SAL_DLLPRIVATE  GenericSalLayout( const GenericSalLayout& );
    SAL_DLLPRIVATE  GenericSalLayout& operator=( const GenericSalLayout& );
};

#undef SalGraphics

#endif // INCLUDED_VCL_INC_SALLAYOUT_HXX

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