#ifndef TILEDWEBVIEW_H

#define TILEDWEBVIEW_H

#include <QGraphicsWebView>

#include <QTime>

#include <QTimer>

#ifdef USE_OWN_TILED_CACHE

#define USE_TILED_CACHE

#endif

//#define USE_ASSISTANT_ITEM

#ifdef USE_ASSISTANT_ITEM

class TiledWebView;

class TiledWebViewAssistant : public QGraphicsWidget {

public:

    void paint(QPainter* painter, const QStyleOptionGraphicsItem* options, QWidget* widget);

    TiledWebView* m_master;

};

#endif

class TiledWebView : public QGraphicsWebView

{

    Q_OBJECT

protected:

    TiledWebView(QGraphicsItem* parent = 0);

    virtual ~TiledWebView();

    struct Tile {

        Tile();

        QPixmap img;

        QRectF dirtyRect; // in tile coordinates

        bool ready;

        bool used;

    };

    struct TileSet {

        TileSet(QPoint aT, QRectF aR) { t = aT; r = aR; }

        TileSet(const TileSet &o) { t = o.t; r = o.r; }

        QPoint t;

        QRectF r;

    };

    void paint(QPainter* painter, const QStyleOptionGraphicsItem* options, QWidget* widget);

    Tile* createTile(const QPoint& p);

    Tile* tileAt(const QPoint& p) const;

    Tile* tileAt(int x, int y) const { return tileAt(QPoint(x, y)); }

    void setTileAt(const QPoint& p,Tile* t);

    void setTileAt(int x, int y,Tile* t) { setTileAt(QPoint(x, y), t); }

    QPoint tileAtPoint(const QPointF& p) const;

    QRectF tileRect(const QPoint& t) const; // return is in tile coords

    QRectF mapToTileCoords(const QRectF& rect) const

        { return QRectF(mapToTileCoords(rect.topLeft()),mapToTileCoords(rect.size())); }

    QPointF mapToTileCoords(const QPointF& p) const     { return p * m_tilesScale; }

    QSizeF mapToTileCoords(const QSizeF& s) const     { return s * m_tilesScale; }

    QRectF mapFromTileCoords(const QRectF& rect) const

        { return QRectF(mapFromTileCoords(rect.topLeft()),mapFromTileCoords(rect.size())); }

    QPointF mapFromTileCoords(const QPointF& p) const     { return p / m_tilesScale; }

    QSizeF mapFromTileCoords(const QSizeF& s) const     { return s / m_tilesScale; }

    QRectF viewPortRect() const;

    QPoint findTile4Update(bool inView, bool addDirty = false) const;

    QList<QPoint> findTileLine4Update(bool dirty, bool inView, bool useScrollDirection = true) const;

    void boundTile(QPoint& t) const;

    QRectF updateTile(const QPoint& t);

    void paintTile(QPainter* painter, const QPoint& t, const QRectF& dirtyRect, QRegion& dirtyRegion);

    void createTileField();

    QRectF validateTileRect(const QRectF& rect, const QSize& dim) const;

    QRectF adjustedTileRect(const QSize& dim) const;

    QRectF centeredTileRect(const QSize& dim) const;

    void adjustTilesToViewPort(bool center = false);

    void moveTilesRect(const QRectF& newTilesRect);

    void resetTiles(const QRect& r, bool remove);

    void scrollTileField(const QPoint& diff);

    static QPixmap* getUnprepPixmap();

    void checkTilesField();

    void setPage(QWebPage* page);

    QList<QRectF> updateViewportTiles(QList<TileSet> *updatedTiles = 0);

    QList<QRectF> updateScrollAreaTilesChunk(QList<TileSet> *updatedTiles = 0, bool inPaint = 0);

    void doScaleCommit();

    void doTilesFieldRebuild();

    void updateSceneRects(const QList<QRectF>& dirtyTiles);

#ifdef USE_ASSISTANT_ITEM

    void resizeEvent(QGraphicsSceneResizeEvent *event);

#endif

    QSize getTileFieldDim();

    QVector<Tile*> m_tilesPool;

    Tile** m_tilesField;

    QSize  m_tilesDim;

    QRectF m_tilesRect;

    qreal  m_tilesScale;

    bool   m_inUpdate;

    bool   m_tilesRectCentered;

    QTime  m_userPaintTS;

    QTimer m_updateTimer;

    bool   m_tilesFrozen;

    bool   m_needViewportTilesUpdate;

    bool   m_needScaleCommit;

    bool   m_needTilesFieldRebuild;

    QPoint m_lastScrollDelta;

#ifdef USE_ASSISTANT_ITEM

    TiledWebViewAssistant* m_assistant;

#endif // USE_ASSISTANT_ITEM

private slots:

    void repaintRequested(QRect);

    void updateTimeout();

    void scheduleScaleUpdate();

    void startUpdateTimer();

    void stopUpdateTimer();

    void loadStarted();

public slots:

    void viewportUpdated();

    void commitZoom();

    void setTiledBackingStoreFrozen(bool frozen);

    void userActivity();

    void viewScrolled(QPoint& scrollPos, QPoint& delta);

  friend class TiledWebViewAssistant;

};

#endif // TILEDWEBVIEW_H