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

#ifndef TB_SCROLL_CONTAINER_H
#define TB_SCROLL_CONTAINER_H

#include "tb_widgets_common.h"

namespace tb {

enum SCROLL_MODE {
    SCROLL_MODE_X_Y,			///< X and Y always			scroll-mode: xy
    SCROLL_MODE_Y,				///< Y always (X never)		scroll-mode: y
    SCROLL_MODE_Y_AUTO,			///< Y auto (X never)		scroll-mode: y-auto
    SCROLL_MODE_X_AUTO_Y_AUTO,	///< X auto, Y auto			scroll-mode: auto
    SCROLL_MODE_OFF				///< X any Y never			scroll-mode: off
};

/** TBScrollContainerRoot - Internal for TBScrollContainer */

class TBScrollContainerRoot : public TBWidget
{
private: // May only be used by TBScrollContainer.
    friend class TBScrollContainer;
    TBScrollContainerRoot() {}
public:
    virtual void OnPaintChildren(const PaintProps &paint_props);
    virtual void GetChildTranslation(int &x, int &y) const;
};

/** TBScrollBarVisibility - Helper for TBScrollContainer or any other scrollable
    container that needs to solve scrollbar visibility according to SCROLL_MODE. */
class TBScrollBarVisibility
{
public:
    TBScrollBarVisibility () : x_on(false), y_on(false), visible_w(0), visible_h(0) {}

    static TBScrollBarVisibility Solve(SCROLL_MODE mode, int content_w, int content_h,
                                       int available_w, int available_h,
                                       int scrollbar_x_h, int scrollbar_y_w);
    static bool IsAlwaysOnX(SCROLL_MODE mode) { return mode == SCROLL_MODE_X_Y; }
    static bool IsAlwaysOnY(SCROLL_MODE mode) { return mode == SCROLL_MODE_X_Y || mode == SCROLL_MODE_Y; }
public:
    bool x_on, y_on;
    int visible_w, visible_h;
};

/** TBScrollContainer - A container with scrollbars that can scroll its children. */

class TBScrollContainer : public TBWidget
{
    friend class TBScrollContainerRoot;
public:
    // For safe typecasting
    TBOBJECT_SUBCLASS(TBScrollContainer, TBWidget);

    TBScrollContainer();
    ~TBScrollContainer();

    /** Set to true if the preferred size of this container should adapt to the preferred
        size of the content. This is disabled by default. */
    void SetAdaptToContentSize(bool adapt);
    bool GetAdaptToContentSize() { return m_adapt_to_content_size; }

    /** Set to true if the content should adapt to the available size of this container
        when it's larger than the preferred size. */
    void SetAdaptContentSize(bool adapt);
    bool GetAdaptContentSize() { return m_adapt_content_size; }

    void SetIgnoreScrollEvents(bool ignore) { m_ignore_scroll_events = ignore; }

    void SetScrollMode(SCROLL_MODE mode);
    SCROLL_MODE GetScrollMode() { return m_mode; }

    virtual void ScrollTo(int x, int y);
    virtual TBWidget::ScrollInfo GetScrollInfo();
    virtual TBWidget *GetScrollRoot() { return &m_root; }

    virtual void InvalidateLayout(INVALIDATE_LAYOUT il);

    virtual TBRect GetPaddingRect();
    virtual PreferredSize OnCalculatePreferredContentSize(const SizeConstraints &constraints);

    virtual void OnInflate(const INFLATE_INFO &info);
    virtual bool OnEvent(const TBWidgetEvent &ev);
    virtual void OnProcess();
    virtual void OnResized(int old_w, int old_h);

    virtual TBWidget *GetContentRoot() { return &m_root; }
protected:
    TBScrollBar m_scrollbar_x;
    TBScrollBar m_scrollbar_y;
    TBScrollContainerRoot m_root;
    bool m_adapt_to_content_size;
    bool m_adapt_content_size;
    bool m_layout_is_invalid;
    bool m_ignore_scroll_events;
    SCROLL_MODE m_mode;
    void ValidateLayout(const SizeConstraints &constraints);
};

};

#endif // TB_SCROLL_CONTAINER_H