/**
 * @file PaiHeaderView.cpp
 * @date 2012-11-09
 */
#include <QPainter>
#include <QApplication>
#include <QMouseEvent>
#include <QToolButton>
#include <QMenu>
#include <QCheckBox>

#include "PaiHeaderView.h"
#include "PaiSettings.h"

const int SORT_ARRAW_LEN  = 30; // 可以排序时右侧的盘需模式指示标记宽度
const int LAST_SECTION_ADD_SPACE_LEN  = 15; //最后一列加点空隙不让pSectionSelectTBtn遮挡

#define LOGICAL_INDEX "logic index" //QCheckBox用于记录自身所属逻辑列数

using namespace pai::gui;

PaiHeaderView::PaiHeaderView(Qt::Orientation orientation, QWidget *pParent)
    : QHeaderView(orientation, pParent),
    m_SectionSelectableVisible(false)
{
    m_pSectionSelectToolButton = new QToolButton(this);
    // 该ToolButton底色需与HeaderView底色保持一致
    m_pSectionSelectToolButton->setStyleSheet(QString::fromUtf8("background-color: qlineargradient(x1:0, y1:0, x2:0, y2:1, \n"
                                    "stop:0 #FEFEFF, stop:1 #E9F2F8);\n"
                                    "border-left: 1px solid #C9D5DC;\n"
                                    "border-right: 0px;\n"
                                    "border-top: 1px solid #C9D5DC;\n"
                                    "border-bottom: 1px solid #C9D5DC;"));
    m_pSectionSelectToolButton->setIcon(QIcon(":/add_01.png"));
    m_pSectionSelectToolButton->setVisible(m_SectionSelectableVisible);

    // setClickable(true);
    setStretchLastSection(true);    // PAI风格默认

    connect(this, SIGNAL(sectionResized(int, int, int)),
            this, SLOT(AdjustSectionSuitable(int, int, int)));
    connect(m_pSectionSelectToolButton, SIGNAL(clicked()),
            this, SLOT(ShowSectionVisibleMenu()));
}

PaiHeaderView::~PaiHeaderView()
{
}

void PaiHeaderView::SetSectionVisibleSelectable(bool selectable)
{
    m_SectionSelectableVisible = selectable;
    m_pSectionSelectToolButton->setVisible(m_SectionSelectableVisible);
}

void PaiHeaderView::paintSection(QPainter *pPainter, const QRect & rect, int logicalIndex) const
{
    // 当显示列选择功能时，需单独绘制最后一列，以使标题信息不被选择按钮挡住
    if(m_SectionSelectableVisible && (logicalIndex == LastVisibleSection()))
    {
        int adjustSize = m_pSectionSelectToolButton->width()-1; // -1px来保证做测边界只有一个边被显示

        // 分两部分绘制，此处为前半部分
        QHeaderView::paintSection(pPainter, rect.adjusted(0, 0, -adjustSize, 0), logicalIndex);

        // 后半部分，其实就是不绘制任何图像
        QStyleOptionHeader opt;
        initStyleOption(&opt);
        opt.sortIndicator = QStyleOptionHeader::None;
        opt.rect = rect.adjusted(rect.width() - adjustSize, 0, 0, 0);
        opt.section = logicalIndex;
        opt.position = QStyleOptionHeader::End;
        QApplication::style()->drawControl(QStyle::CE_Header, &opt, pPainter, this);
    }
    else    // 其它列绘制
    {
        QHeaderView::paintSection(pPainter, rect, logicalIndex);
    }

    // 调整CheckBox位置
    if(m_ColumnCheckBoxMap.contains(logicalIndex))
    {
        QCheckBox *pCheckBox = m_ColumnCheckBoxMap.value(logicalIndex);

        int x = rect.x(); //靠左
        int y = (rect.height() - pCheckBox->height()) / 2; //垂直居中

        pCheckBox->move(x, y);
    }
}

void PaiHeaderView::resizeEvent(QResizeEvent *pEvent)
{
    QHeaderView::resizeEvent(pEvent);

    // 使列选择按钮始终在表格右上角
    if(m_SectionSelectableVisible)
    {
        m_pSectionSelectToolButton->resize(height(), height());
        m_pSectionSelectToolButton->move(width()-height(), 0);
    }
}

void PaiHeaderView::mousePressEvent(QMouseEvent *pEvent)
{
    QHeaderView::mousePressEvent(pEvent);

    if(Qt::RightButton == pEvent->button())
    {
        emit TitleRightClicked(logicalIndexAt(pEvent->pos()), pEvent->globalPos());
    }
}

void PaiHeaderView::ShowSectionVisibleMenu()
{
    QMenu contextMenu;

    for(int i = 0; i < count(); ++i)
    {
        QString colText = model()->headerData(i, Qt::Horizontal).toString();
        if(!m_UnselectableSections.contains(colText))
        {
            QAction *pVisibleAct = contextMenu.addAction(colText, this, SLOT(ReverseSectionVisible()));
            pVisibleAct->setCheckable(true);
            pVisibleAct->setChecked(!isSectionHidden(i));
            pVisibleAct->setData(i);    // 以该值来标记action所代表的列
        }
    }

    contextMenu.exec(mapToGlobal(m_pSectionSelectToolButton->geometry().bottomLeft()));
}

void PaiHeaderView::CheckBoxStateChanged()
{
    QCheckBox *pCheckBox = dynamic_cast<QCheckBox *>(sender());

    if(pCheckBox != NULL)
    {
        emit CheckStateChanged(pCheckBox->property(LOGICAL_INDEX).toInt(), pCheckBox->checkState());
    }
}

void PaiHeaderView::ReverseSectionVisible()
{
    QAction *pAct = qobject_cast<QAction*>(sender());

    if(pAct)
    {
        int index = LastVisibleSection();  // 显示列索引变为逻辑索引
        if((index >= 0) && (index < count()))
        {
            int size = SectionSuitableWidth(index);
            if(sectionSize(index) > size)
            {
                resizeSection(index, size);
            }
        }

        int sectionIndex = pAct->data().toInt();
        if((sectionIndex >= 0) && (sectionIndex < count())) // 判断逻辑索引是否超出范围
        {
            SetSectionHidden(sectionIndex, !isSectionHidden(sectionIndex)); // 交换显示状态
            // 隐藏一列后将最后一列重新resize下，不让pSectionSelectTBtn遮挡住
            resizeSection (LastVisibleSection(), SectionSuitableWidth(LastVisibleSection()));
        }
    }
}

void PaiHeaderView::RememberCurrentSections()
{
    if(!m_SectionSelectableVisible)
    {
        return;
    }
    if(parent() == NULL)
    {
        return;
    }
    // 生成对应的KEY
    QString objName = parent()->objectName();
    if(objName.isEmpty())
    {
        return;
    }
    QString key = objName.append("_VISIBLE_SECTIONS");

    // 将当前显示的列索引记录到sections中
    QStringList sections;
    int cn = count();
    for(int i = 0; i < cn; i++)
    {
        if(!isSectionHidden(i))
        {
            sections.append(QString::number(i));
        }
    }

    PaiSettings settings;
    settings.setValue(key, sections.join(","));
}

void PaiHeaderView::SetColumnCheckable(const int logicalIndex, const bool checkable, QCheckBox *pCheckBox)
{
    if(checkable)
    {
        pCheckBox->setParent(this);
        pCheckBox->setProperty(LOGICAL_INDEX, QString::number(logicalIndex));
        pCheckBox->setFixedSize(20, 20);
        connect(pCheckBox, SIGNAL(stateChanged(int)), this, SLOT(CheckBoxStateChanged()));

        m_ColumnCheckBoxMap.insert(logicalIndex, pCheckBox);
    }
    else
    {
        //从Map移除，并返回NULL
        if(m_ColumnCheckBoxMap.contains(logicalIndex))
        {
            delete m_ColumnCheckBoxMap.value(logicalIndex);
            m_ColumnCheckBoxMap.remove(logicalIndex);
        }
    }

    update();
}

void PaiHeaderView::AdjustCheckBoxMap(bool insert, int column)
{
    QMap<int, QCheckBox*> newMap;

    if(insert)
    {
        //如果为插入操作，则将插入所在序列后的列序号+1
        foreach(int index , m_ColumnCheckBoxMap.keys())
        {
            if(index < column)
            {
                newMap.insert(index, m_ColumnCheckBoxMap.value(index));
            }
            else
            {
                newMap.insert(index + 1, m_ColumnCheckBoxMap.value(index));

                // 调整CheckBox对应的逻辑列
                QCheckBox *pCheckBox = newMap.value(index + 1);
                if(pCheckBox != NULL)
                {
                    pCheckBox->setProperty(LOGICAL_INDEX, QString::number(index + 1));
                }
            }
        }
    }
    else
    {
        // 如果为删除操作，则将删除所在序列后的列序号-1
        foreach(int index , m_ColumnCheckBoxMap.keys())
        {
            if(index < column)
            {
                newMap.insert(index, m_ColumnCheckBoxMap.value(index));
            }
            else if(index == column)
            {
                // 如果此行为删除行，则将CheckBox解析掉
                QCheckBox *pCheckBox = m_ColumnCheckBoxMap.value(index);
                if(pCheckBox != NULL)
                {
                    delete pCheckBox;
                    pCheckBox = NULL;
                }
            }
            else
            {
                newMap.insert(index - 1, m_ColumnCheckBoxMap.value(index));

                // 调整CheckBox对应的逻辑列
                QCheckBox *pCheckBox = newMap.value(index - 1);
                if(pCheckBox != NULL)
                {
                    pCheckBox->setProperty(LOGICAL_INDEX, QString::number(index - 1));
                }
            }
        }
    }

    // 替换为调整后的Map
    m_ColumnCheckBoxMap = newMap;
    update();
}

void PaiHeaderView::RecallMemberedSections()
{
    if(!m_SectionSelectableVisible)
    {
        return;
    }

    if(parent() == NULL)
    {
        return;
    }

    QString objName = parent()->objectName();
    if(objName.isEmpty())
    {
        return;
    }
    // 生成当前表格显示列记录的KEY
    QString key = objName.append("_VISIBLE_SECTIONS");
    PaiSettings setting;
    if(setting.contains(key))
    {
        int count = this->count();
        // 余下可隐藏的默认显示列也设置其为隐藏
        for(int i = 0; i < count; i++)
        {
            QString colText = model()->headerData(i, Qt::Horizontal).toString();
            if(!m_UnselectableSections.contains(colText))
            {
                SetSectionHidden(i, true);
            }
        }

        QString value = setting.value(key).toString();
        if(value.isEmpty())
        {
            return;
        }
        QStringList indexs = value.split(",");

        int size = indexs.size();
        bool ok;
        for(int i = 0; i < size; i++)
        {
            int index = indexs.at(i).toInt(&ok, 10);
            if(ok && (index < count) && (index >= 0))
            {
                SetSectionHidden(index, false);
            }
        }
    }
}

void PaiHeaderView::SetSectionHidden(int logicalIndex, bool hide)
{
    setSectionHidden(logicalIndex, hide);
    emit SectionVisibleChanged(logicalIndex, !hide);
}

void PaiHeaderView::AdjustSectionSuitable(int logicalIndex, int /*oldSize*/, int newSize)
{
    // 为0的时候，认为其将要被隐藏，这时就不能再限制它的长度，注意这里使用isSectionHidden无效
    if(newSize != 0)
    {
        int sSize = SectionSuitableWidth(logicalIndex); // 获得该列的最适大小
        if(newSize < sSize) // 当最新的宽度小于最适大小时，重新调整其大小
        {
            resizeSection(logicalIndex, sSize);
        }
    }
}

int PaiHeaderView::SectionSuitableWidth(int logicalIndex)
{
    // 文本长度
    int sw = fontMetrics().width(model()->headerData(logicalIndex, Qt::Horizontal).toString());
    if(isSortIndicatorShown()) // 当有排序箭头时，加上该箭头的宽度
    {
        sw += SORT_ARRAW_LEN;
    }
    if(m_SectionSelectableVisible && (logicalIndex == LastVisibleSection())) // 当时最后显示列的时候，加上列选择按钮宽度
    {
        sw += m_pSectionSelectToolButton->width();
        sw += LAST_SECTION_ADD_SPACE_LEN;//加长点要不最后一列的后两个字母被pSectionSelectTBtn遮挡
    }
    return sw;
}

int PaiHeaderView::LastVisibleSection() const
{
    for(int i = count() - 1; i >= 0; --i)
    {
        int lgIndex = logicalIndex(i); // 显示列索引变为逻辑索引
        if(!isSectionHidden(lgIndex))
        {
            return lgIndex;
        }
    }

    return -1;
}

void PaiHeaderView::SetUnselectableSections(const QStringList & sectionList)
{
    m_UnselectableSections = sectionList;
}