#include "TableHeaderView.h"
#include <QCheckBox>
#include <QApplication>
#include <QMouseEvent>
#include <qmessagebox.h>

#ifdef _MSC_VER
#pragma execution_character_set("utf-8")
#endif

#define CHECK_BOX_COLUMN 0
TableHeaderView::TableHeaderView(Qt::Orientation orientation, QWidget *parent)
    : QHeaderView(orientation, parent),
    m_bPressed(false),
    m_bChecked(false),
    m_bTristate(false),
    m_bNoChange(false),
    m_bMoving(false)

{
    setSectionsClickable(true); // 响应鼠标
}

TableHeaderView::~TableHeaderView()
{

}

// 槽函数，用于更新复选框状态
void TableHeaderView::onStateChanged(int state)
{
    if (state == Qt::PartiallyChecked) {
        m_bTristate = true;
        m_bNoChange = true;
    }
    else {
        m_bNoChange = false;
    }

    m_bChecked = (state != Qt::Unchecked);
    update();
}

// 绘制复选框
void TableHeaderView::paintSection(QPainter *painter, const QRect &rect, int logicalIndex) const
{
    painter->save();
    QHeaderView::paintSection(painter, rect, logicalIndex);
    painter->restore();

    if (logicalIndex == CHECK_BOX_COLUMN )
    {
        QStyleOptionButton option;
        option.initFrom(this);

        if (m_bChecked)
            option.state |= QStyle::State_Sunken;

        if (m_bTristate && m_bNoChange)
            option.state |= QStyle::State_NoChange;
        else
            option.state |= m_bChecked ? QStyle::State_On : QStyle::State_Off;
        if (testAttribute(Qt::WA_Hover) && underMouse()) {
            if (m_bMoving)
                option.state |= QStyle::State_MouseOver;
            else
                option.state &= ~QStyle::State_MouseOver;
        }

        QCheckBox checkBox;
        option.iconSize = QSize(20, 20);
        option.rect = rect;
        style()->drawPrimitive(QStyle::PE_IndicatorCheckBox, &option, painter, &checkBox);
    }
}

// 鼠标按下表头
void TableHeaderView::mousePressEvent(QMouseEvent *event)
{
    int nColumn = logicalIndexAt(event->pos());
    if ((event->buttons() & Qt::LeftButton) && (nColumn == CHECK_BOX_COLUMN))
    {
        m_bPressed = true;
    }
    else
    {
        QHeaderView::mousePressEvent(event);
    }
}

// 鼠标从表头释放，发送信号，更新model数据
void TableHeaderView::mouseReleaseEvent(QMouseEvent *event)
{

    if (m_bPressed)
    {
        if (m_bTristate && m_bNoChange)
        {
            m_bChecked = true;
            m_bNoChange = false;
        }
        else
        {
            m_bChecked = !m_bChecked;
        }

        update();

        Qt::CheckState state = m_bChecked ? Qt::Checked : Qt::Unchecked;

        emit stateChanged(state);

        updateSection(0);
    }
    else
    {
        QHeaderView::mouseReleaseEvent(event);
    }

    m_bPressed = false;
}

// 鼠标滑过、离开，更新复选框状态
bool TableHeaderView::event(QEvent *event)
{
    updateSection(0);
    if (event->type() == QEvent::Enter || event->type() == QEvent::Leave)
    {
        QMouseEvent *pEvent = static_cast<QMouseEvent *>(event);
        int nColumn = logicalIndexAt(pEvent->x());
        if (nColumn == CHECK_BOX_COLUMN)
        {
            m_bMoving = (event->type() == QEvent::Enter);

            update();
            return true;
        }
    }
    return QHeaderView::event(event);
}




CheckBoxDelegate::CheckBoxDelegate(QObject *parent) :QStyledItemDelegate(parent)
{

}

CheckBoxDelegate::~CheckBoxDelegate()
{

}

// 绘制复选框
void CheckBoxDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    QStyleOptionViewItem viewOption(option);
    initStyleOption(&viewOption, index);
    if (option.state.testFlag(QStyle::State_HasFocus))
        viewOption.state = viewOption.state ^ QStyle::State_HasFocus;

    QStyledItemDelegate::paint(painter, viewOption, index);

    if (index.column() == CHECK_BOX_COLUMN )
    {
        bool data = index.model()->data(index, Qt::UserRole).toBool();

        QStyleOptionButton checkBoxStyle;
        checkBoxStyle.state = data ? QStyle::State_On : QStyle::State_Off;
        checkBoxStyle.state |= QStyle::State_Enabled;
        checkBoxStyle.iconSize = QSize(20, 20);
        checkBoxStyle.rect = option.rect;

        QCheckBox checkBox;
        checkBoxStyle.iconSize = QSize(20, 20);
        checkBoxStyle.rect = option.rect;
        QApplication::style()->drawPrimitive(QStyle::PE_IndicatorCheckBox, &checkBoxStyle, painter, &checkBox);

        checkBox.setEnabled(false);
    }
}

// 响应鼠标事件，更新数据
bool CheckBoxDelegate::editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index)
{
    QRect decorationRect = option.rect;

    QMouseEvent *mouseEvent = static_cast<QMouseEvent *>(event);
    if (event->type() == QEvent::MouseButtonPress && decorationRect.contains(mouseEvent->pos()))
    {
        if (index.column() == CHECK_BOX_COLUMN )
        {

                bool data = model->data(index, Qt::UserRole).toBool();
                model->setData(index, !data, Qt::UserRole);

        }
    }

    return QStyledItemDelegate::editorEvent(event, model, option, index);
}