/**
 * @file PaiTitleBar.cpp
 * @date 2012-11-29
 */
#include <QMouseEvent>
#include <QHBoxLayout>
#include <QPainter>
#include <QMenu>

#include "PaiTitleBar.h"
#include "PaiToolButton.h"

using namespace pai::gui;

const int titleBarHeight = 30;
const int titleNameCenterStand = 1300; // titlename默认采用titlebar整个宽幅居中，当titlebar宽幅小于此值时，为显示美观及避免文字被遮挡采用titlebar空白居中
const int titleSpaceCenterStand = 300; // 当titlebar整个除去标题文字后的空白小于此值时，为显示美观采用titlebar空白居中

PaiStatusBar::PaiStatusBar(QWidget *pParent) :
    QStatusBar(pParent)
{
    setObjectName("PaiStatusBar");
    setSizeGripEnabled(false);
    setStyleSheet("QStatusBar#PaiStatusBar{background-color: #E4EEFA}");
}

PaiStatusBar::~PaiStatusBar()
{
}

///////////////////////////////////////////////
PaiTitleBar::PaiTitleBar(QWidget *parent) :
    QWidget(parent)
{
    setMaximumHeight(titleBarHeight);
    setMinimumHeight(titleBarHeight);

    setContentsMargins(0, 0, 0, 0);

    m_pMinimumButton = new PaiToolButton(this);
    m_pMinimumButton->setObjectName("MinimumButton");

    m_pMaximumButton = new PaiToolButton(this);
    m_pMaximumButton->setObjectName("MaximumButton");

    m_pExitButton = new PaiToolButton(this);
    m_pExitButton->setObjectName("ExitButton");

    m_pLogoButton = new PaiToolButton(this);
    m_pLogoButton->setObjectName("LogoButton");

    QSize size = QSize(titleBarHeight, titleBarHeight);
    m_pMinimumButton->setFocusPolicy(Qt::NoFocus);
    m_pMinimumButton->setMaximumSize(size);
    m_pMinimumButton->setMinimumSize(size);

    m_pMaximumButton->setFocusPolicy(Qt::NoFocus);
    m_pMaximumButton->setMaximumSize(size);
    m_pMaximumButton->setMinimumSize(size);

    m_pExitButton->setFocusPolicy(Qt::NoFocus);
    m_pExitButton->setMaximumSize(QSize(size.width() + 10, size.height()));
    m_pExitButton->setMinimumSize(QSize(size.width() + 10, size.height()));

    m_pLogoButton->setFocusPolicy(Qt::NoFocus);
    m_pLogoButton->setMaximumSize(size);
    m_pLogoButton->setMinimumSize(size);

    m_pRightHLayout = new QHBoxLayout;
    m_pRightHLayout->setContentsMargins(0, 0, 0, 0);
    m_pRightHLayout->setSpacing(0);
    m_pRightHLayout->setSizeConstraint(QLayout::SetDefaultConstraint);

    m_pLeftHLayout = new QHBoxLayout;
    m_pLeftHLayout->setContentsMargins(0, 0, 0, 0);
    m_pLeftHLayout->setSpacing(0);
    m_pLeftHLayout->setSizeConstraint(QLayout::SetDefaultConstraint);

    QHBoxLayout *pMainHLayout = new QHBoxLayout(this);
    pMainHLayout->setContentsMargins(0, 0, 0, 0);
    pMainHLayout->setSpacing(0);
    pMainHLayout->setSizeConstraint(QLayout::SetDefaultConstraint);

    m_pLeftHLayout->addWidget(m_pLogoButton);

    m_pRightHLayout->addWidget(m_pMinimumButton);
    m_pRightHLayout->addWidget(m_pMaximumButton);
    m_pRightHLayout->addWidget(m_pExitButton);

    pMainHLayout->addLayout(m_pLeftHLayout);
    pMainHLayout->addStretch(1);
    pMainHLayout->addLayout(m_pRightHLayout);
    setLayout(pMainHLayout);

    connect(m_pExitButton, SIGNAL(clicked()), this, SIGNAL(HandleExitButton()));
    connect(m_pMinimumButton, SIGNAL(clicked()), this, SIGNAL(HandleMinimumButton()));
    connect(m_pMaximumButton, SIGNAL(clicked()), this, SIGNAL(HandleMaximumButton()));
    connect(m_pMaximumButton, SIGNAL(clicked()), this, SLOT(ChangeRestoreButtonState()));
    connect(m_pLogoButton, SIGNAL(pressed()), m_pLogoButton, SLOT(showMenu()));

    setStyleSheet("QToolButton{background-color:qlineargradient(x1:0,y1:0,x2:0,y2:1,stop:0 #F3F9FE,stop:1 #C9DDEB);"
        "            border:0px}"
        "QToolButton::menu-indicator{image:None}"
        "QToolButton#ExitButton{border-image:url(:/Close_a.png)}"
        "QToolButton#ExitButton:hover{background-image:url(:/Close_hover.png);"
        "                             border-style:none}"
        "QToolButton#ExitButton:pressed{background-image:url(:/Close_click.png);"
        "                               border-style:none}"
        "QToolButton#MaximumButton{border-image:url(:/minimize_status.png)}"
        "QToolButton#MaximumButton:hover{background-image:url(:/Minimize_hover.png);"
        "                             border-style:none}"
        "QToolButton#MaximumButton:pressed{background-image:url(:/Minimize_click.png);"
        "                               border-style:none}"
        "QToolButton#MinimumButton{border-image:url(:/Minimize.png)}"
        "QToolButton#MinimumButton:hover{background-image:url(:/Minimize_hover.png);"
        "                             border-style:none}"
        "QToolButton#MinimumButton:pressed{background-image:url(:/Minimize_click.png);"
        "                               border-style:none}"

        "QToolButton#LogoButton{border-image:url(:/Logo_a.png)}");

    // 默认仅显示最小化，最大化和关闭按钮
    SetTitleBarFlags(CloseButtonHint | MaximumButtonHint | MinimumButtonHint);
}

PaiTitleBar::~PaiTitleBar()
{
}

void PaiTitleBar::resizeEvent(QResizeEvent *pEvent)
{
    int nowSizeWidth = pEvent->size().width();
    int basicStringWidth = 20;
    int buttonWidth = 0;

    QList< PaiToolButton * > lstToolButton;

    if(m_titleBarFlags & PaiTitleBar::LogoButtonHint)
    {
        lstToolButton.append(m_pLogoButton);
    }
    if(m_titleBarFlags & PaiTitleBar::CloseButtonHint)
    {
        lstToolButton.append(m_pExitButton);
    }
    if(m_titleBarFlags & PaiTitleBar::MaximumButtonHint)
    {
        lstToolButton.append(m_pMaximumButton);
    }
    if(m_titleBarFlags & PaiTitleBar::MinimumButtonHint)
    {
        lstToolButton.append(m_pMinimumButton);
    }

    for(int i = 0; i < lstToolButton.size(); ++i)
    {
        lstToolButton[i]->hide();
    }

    for(int i = 0; i < lstToolButton.size(); ++i)
    {
        buttonWidth += lstToolButton[i]->size().width();
        if(nowSizeWidth - buttonWidth > basicStringWidth)
        {
            lstToolButton[i]->show();
        }
    }

    QWidget::resizeEvent(pEvent);
}
void PaiTitleBar::paintEvent(QPaintEvent *pEvent)
{
    int iPixelTitile = fontMetrics().width(m_title);
    QRect titleRect = GetTitleNameRect(iPixelTitile);
    QString elidedTitle = fontMetrics().elidedText(m_title, Qt::ElideRight, titleRect.width());

    QLinearGradient linearGradient(0, 0, 0, titleBarHeight);
    linearGradient.setColorAt(0.0, QColor("#F3F9FE"));
    linearGradient.setColorAt(1.0, QColor("#C9DDEB"));

    QWidget::paintEvent(pEvent);
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, true);
    painter.fillRect(rect(), QBrush(linearGradient));
    painter.setBrush(QBrush(Qt::black));
    painter.drawText(titleRect, Qt::AlignCenter, elidedTitle);
}

QRect PaiTitleBar::GetTitleNameRect(int pixelTitle)
{
    QRect titleRect;
    int wdif = qAbs(m_pRightHLayout->geometry().width() - m_pLeftHLayout->geometry().width());
    int iSpaceWidth = this->width() - m_pRightHLayout->geometry().width() - m_pLeftHLayout->geometry().width();
    int iSpaceLeave = (titleSpaceCenterStand >= wdif) ? titleSpaceCenterStand : wdif;

    if(iSpaceWidth - pixelTitle <= iSpaceLeave) // 如果空白区域少于指定值，采用空白居中
    {
        titleRect = QRect(m_pLeftHLayout->geometry().topRight(), m_pRightHLayout->geometry().bottomLeft());
    }
    else
    {
        float fScale = 0.5; // 渐变因子
        int iPosx = titleNameCenterStand - wdif / fScale;   // 由空白居中到标题栏居中渐变的起始宽度

        if(this->width() <= iPosx)  // 当标题栏宽度小于起始宽度时，直接采用空白居中
        {
            titleRect = QRect(m_pLeftHLayout->geometry().topRight(), m_pRightHLayout->geometry().bottomLeft());
        }
        else
        {
            int offset = (this->width() - iPosx) * fScale; // 偏移量

            if(offset >= wdif) // 当偏移量大于宽度差值，采用标题栏居中
            {
                int iPox2 = m_pRightHLayout->geometry().width()
                        + m_pLeftHLayout->geometry().width()
                        + pixelTitle
                        + iSpaceLeave
                        + wdif / fScale;//标题文字较长时，由标题栏到空白居中渐变的起始宽度
                QPoint bottomleftPt = m_pRightHLayout->geometry().bottomRight();

                if(this->width() < iPox2)   // 当标题栏宽度小于渐变宽度时，采用标题栏-offset居中
                {
                    offset = (iPox2 - this->width()) * fScale;
                    if(offset < wdif)
                    {
                        bottomleftPt.setX(bottomleftPt.x() - offset);
                    }
                }

                titleRect = QRect(m_pLeftHLayout->geometry().topLeft(), bottomleftPt);
            }
            else    // 当偏移量小于宽度差值，采用空白+offset居中
            {
                QPoint bottomleftPt = m_pRightHLayout->geometry().bottomLeft();
                bottomleftPt.setX(bottomleftPt.x() + offset);
                titleRect = QRect(m_pLeftHLayout->geometry().topRight(), bottomleftPt);
            }
        }
    }
    return titleRect;
}

void PaiTitleBar::mousePressEvent(QMouseEvent *pEvent)
{
    QWidget::mousePressEvent(pEvent);
    // 左键+有父控件+没触发resize事件（暂时用鼠标样式判断）
    if((pEvent->button() == Qt::LeftButton) && parentWidget() && (cursor().shape() == Qt::ArrowCursor))
    {
        m_MovePosition = pEvent->globalPos() - parentWidget()->frameGeometry().topLeft();
        pEvent->accept();
    }
    else
    {
        pEvent->ignore();
    }
}

void PaiTitleBar::mouseReleaseEvent(QMouseEvent *pEvent)
{
    QWidget::mouseReleaseEvent(pEvent);
    // 左键+有父控件+没触发resize事件（暂时用鼠标样式判断）
    if((pEvent->button() == Qt::LeftButton) && parentWidget() && (cursor().shape() == Qt::ArrowCursor))
    {
        m_MovePosition = QPoint(-1, -1);
        pEvent->accept();
    }
    else
    {
        pEvent->ignore();
    }
}

void PaiTitleBar::mouseMoveEvent(QMouseEvent *pEvent)
{
    QWidget::mouseMoveEvent(pEvent);
    // 左键+有父控件+没触发resize事件（暂时用鼠标样式判断）
    if((pEvent->buttons() & Qt::LeftButton) && parentWidget() && (cursor().shape() == Qt::ArrowCursor))
    {
        if(m_MovePosition != QPoint(-1, -1))
        {
            // 主窗口move事件
            parentWidget()->move(pEvent->globalPos() - m_MovePosition);
            pEvent->accept();
        }
        else
        {
            pEvent->ignore();
        }
    }
}

void PaiTitleBar::mouseDoubleClickEvent(QMouseEvent *pEvent)
{
    QWidget::mouseDoubleClickEvent(pEvent);
    // 左键+有父控件+没触发resize事件（暂时用鼠标样式判断）
    if((pEvent->button() == Qt::LeftButton && parentWidget()) && (cursor().shape() == Qt::ArrowCursor))
    {
        if(parentWidget()->isMaximized())
        {
            parentWidget()->showNormal();
            ChangeRestoreButtonState(false);
        }
        else
        {
            parentWidget()->showMaximized();
            ChangeRestoreButtonState(true);
        }
    }
}

void PaiTitleBar::SetTitle(const QString & strTitle)
{
    m_title = strTitle;
    update();
}

void PaiTitleBar::SetTitleBarFlags(TitleBarFlags flags)
{
    m_pExitButton->setVisible(flags & PaiTitleBar::CloseButtonHint);
    m_pMaximumButton->setVisible(flags & PaiTitleBar::MaximumButtonHint);
    m_pMinimumButton->setVisible(flags & PaiTitleBar::MinimumButtonHint);
    m_pLogoButton->setVisible(flags & PaiTitleBar::LogoButtonHint);

    m_titleBarFlags = flags;
}

PaiTitleBar::TitleBarFlags PaiTitleBar::GetTitleBarFlags() const
{
    return m_titleBarFlags;
}

void PaiTitleBar::CreateSystemMenu(QMenu *pMenu)
{
    m_pLogoButton->setMenu(pMenu);
}

void PaiTitleBar::InsertWidget(QWidget *pWidget, Qt::Alignment alignment)
{
    if(alignment == Qt::AlignRight)
    {
        m_pRightHLayout->insertWidget(0, pWidget);
    }
    else if(alignment == Qt::AlignLeft)
    {
        m_pLeftHLayout->addWidget(pWidget);
    }
}

void PaiTitleBar::ChangeRestoreButtonState()
{
    if(parentWidget())
    {
        if(parentWidget()->isMaximized())
        {
            parentWidget()->showNormal();
            ChangeRestoreButtonState(false);
        }
        else
        {
            parentWidget()->showMaximized();
            ChangeRestoreButtonState(true);
        }
    }
}

void PaiTitleBar::ChangeRestoreButtonState(bool maximized)
{
    if(maximized)
    {
        m_pMaximumButton->setStyleSheet("QToolButton#MaximumButton{border-image:url(:/minimize_status.png)}"
            "QToolButton#MaximumButton:hover{background-image:url(:/Minimize_hover.png);"
            "                             border-style:none}"
            "QToolButton#MaximumButton:pressed{background-image:url(:/Minimize_click.png);"
            "                               border-style:none}");
    }
    else
    {
        m_pMaximumButton->setStyleSheet("QToolButton#MaximumButton{border-image:url(:/maximum.png)}"
            "QToolButton#MaximumButton:hover{background-image:url(:/maximum_hover.png);"
            "                             border-style:none}"
            "QToolButton#MaximumButton:pressed{background-image:url(:/maximum_click.png);"
            "                               border-style:none}");
    }
}