tb_layout.h

// ================================================================================
// ==      This file is a part of Turbo Badger. (C) 2011-2014, Emil Segerås      ==
// ==                     See tb_core.h for more information.                    ==
// ================================================================================

#ifndef TB_LAYOUT_H
#define TB_LAYOUT_H

#include "tb_widgets.h"

namespace tb {

#define SPACING_FROM_SKIN TB_INVALID_DIMENSION

enum LAYOUT_SIZE {
    LAYOUT_SIZE_GRAVITY,    
    LAYOUT_SIZE_PREFERRED,  
    LAYOUT_SIZE_AVAILABLE   
};

enum LAYOUT_POSITION {
    LAYOUT_POSITION_CENTER,         
    LAYOUT_POSITION_LEFT_TOP,       
    LAYOUT_POSITION_RIGHT_BOTTOM,   
    LAYOUT_POSITION_GRAVITY,        
};

enum LAYOUT_DISTRIBUTION {
    LAYOUT_DISTRIBUTION_PREFERRED,  
    LAYOUT_DISTRIBUTION_AVAILABLE,  
    LAYOUT_DISTRIBUTION_GRAVITY     
};

enum LAYOUT_DISTRIBUTION_POSITION {
    LAYOUT_DISTRIBUTION_POSITION_CENTER,        
    LAYOUT_DISTRIBUTION_POSITION_LEFT_TOP,      
    LAYOUT_DISTRIBUTION_POSITION_RIGHT_BOTTOM   
};

enum LAYOUT_ORDER {
    LAYOUT_ORDER_BOTTOM_TO_TOP, 
    LAYOUT_ORDER_TOP_TO_BOTTOM  
};

enum LAYOUT_OVERFLOW {
    LAYOUT_OVERFLOW_CLIP,   
    LAYOUT_OVERFLOW_SCROLL  
    //LAYOUT_OVERFLOW_WRAP
};

class TBLayout : public TBWidget
{
public:
    // For safe typecasting
    TBOBJECT_SUBCLASS(TBLayout, TBWidget);

    TBLayout(AXIS axis = AXIS_X);

    virtual void SetAxis(AXIS axis);
    virtual AXIS GetAxis() const { return m_axis; }

    void SetSpacing(int spacing);
    int GetSpacing() const { return m_spacing; }

    void SetOverflowScroll(int overflow_scroll);
    int GetOverflowScroll() const { return m_overflow_scroll; }

    void SetPaintOverflowFadeout(bool paint_fadeout) { m_packed.paint_overflow_fadeout = paint_fadeout; }

    void SetLayoutSize(LAYOUT_SIZE size);

    void SetLayoutPosition(LAYOUT_POSITION pos);

    void SetLayoutOverflow(LAYOUT_OVERFLOW overflow);

    void SetLayoutDistribution(LAYOUT_DISTRIBUTION distribution);

    void SetLayoutDistributionPosition(LAYOUT_DISTRIBUTION_POSITION distribution_pos);

    void SetLayoutOrder(LAYOUT_ORDER order);

    virtual void InvalidateLayout(INVALIDATE_LAYOUT il);

    virtual PreferredSize OnCalculatePreferredContentSize(const SizeConstraints &constraints);

    virtual void OnInflate(const INFLATE_INFO &info);
    virtual void OnDeflate(const INFLATE_INFO &info);
    virtual WIDGET_HIT_STATUS GetHitStatus(int x, int y);
    virtual bool OnEvent(const TBWidgetEvent &ev);
    virtual void OnPaintChildren(const PaintProps &paint_props);
    virtual void OnProcess();
    virtual void OnResized(int old_w, int old_h);
    virtual void OnInflateChild(TBWidget *child);
    virtual void GetChildTranslation(int &x, int &y) const;
    virtual void ScrollTo(int x, int y);
    virtual TBWidget::ScrollInfo GetScrollInfo();
protected:
    AXIS m_axis;
    int m_spacing;
    int m_overflow;
    int m_overflow_scroll;
    union {
        struct {
            uint32_t layout_is_invalid      : 1;
            uint32_t layout_mode_size           : 4;
            uint32_t layout_mode_pos            : 4;
            uint32_t layout_mode_overflow       : 4;
            uint32_t layout_mode_dist           : 4;
            uint32_t layout_mode_dist_pos       : 4;
            uint32_t mode_reverse_order     : 1;
            uint32_t paint_overflow_fadeout : 1;
        } m_packed;
        uint32_t m_packed_init;
    };
    void ValidateLayout(const SizeConstraints &constraints, PreferredSize *calculate_ps = nullptr);
    bool QualifyForExpansion(WIDGET_GRAVITY gravity) const;
    int GetWantedHeight(WIDGET_GRAVITY gravity, const PreferredSize &ps, int available_height) const;
    TBWidget *GetNextNonCollapsedWidget(TBWidget *child) const;
    int GetTrailingSpace(TBWidget *child, int spacing) const;
    int CalculateSpacing();
    TBWidget *GetFirstInLayoutOrder() const;
    TBWidget *GetNextInLayoutOrder(TBWidget *child) const;
};

};

#endif // TB_LAYOUT_H