#pragma once

#include <iPlotBase_global.h>
#include <QObject>
#include <QHash>
#include <QList>
#include <QRectF>

class ZxRenderItem;
class ZxSceneItem;
class QTimer;
class QTime;

/// 当前选择的图件列表.
/// 已经为大数据量及频繁选择做了优化.
class I_PLOTBASE_EXPORT ZxRenderSelection : public QObject
{
    Q_OBJECT
    struct Node
    {
        ZxRenderItem * item;
        Node  * prev;
        Node  * next;
    };

    static Node * alloc();

    bool m_bChanged;
    Node * head;
    Node * tail;
    QHash<ZxRenderItem*, Node*> dict;

    void listAdd(Node * n);
    void listRemove(Node * n);

    void doAdd(ZxRenderItem * w, bool force);
    void doRemove(Node * n);

    void setChanged();

    QTime * m_pLazyChangedTime;
    QTimer * m_pTimer;
public:
    ZxRenderSelection(ZxSceneItem * pScene);
    ZxSceneItem * getScene();

    /// 选择
    void add(ZxRenderItem * p, bool force = false);
    /// 取消选择
    void remove(ZxRenderItem * p);
    /// 反选
    void invert(ZxRenderItem * p, bool force = false);

    void clear();

    ZxRenderItem * first() const;
    ZxRenderItem * last() const;

    QList<ZxRenderItem *> toList();

    class I_PLOTBASE_EXPORT const_iterator
    {
        Node * p;
        const_iterator(Node * p);
    public:
        ZxRenderItem * operator*();
        bool operator!=( const const_iterator& ) const;
        bool operator==( const const_iterator& ) const;
        const_iterator& operator++();
        friend class ZxRenderSelection;
    };

    const_iterator begin() const;
    const_iterator end() const;

    bool empty() const;
    bool isEmpty() const;
    bool isSingle() const;
    int  count() const;

    QRectF getBounds();

    bool hasSameParent() const;

    void move(float dx, float dy);

signals:

    /// 个别图件被加进列表
    void sigItemAdded(ZxRenderItem * p);

    /// 个别图件被从列表移除
    void sigItemRemoved(ZxRenderItem * p);

    /// 选中列表被改变(即时)
    void sigSelectionChanged();

    /// 选中列表被改变(非即时)
    void sigSelectionChangedLazy();


protected:
    friend class ZxRenderView;
   // ZxRenderSelection();
   // ~ZxRenderSelection();
protected slots:
    virtual void onTimer();
private:
    ZxSceneItem * m_pScene;
    ZxRenderSelection(const ZxRenderSelection & c);
};