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#include "messageboxhandler.h"

#include <QtCore/QDebug>

#include <QApplication>
#include <QDialogButtonBox>
#include <QPushButton>

/*!
    \qmltype QMessageBox
    \inqmlmodule scripting

    \brief The QMessageBox type provides a modal dialog for informing the
    user or asking the user a question and receiving an answer.


    \code
    var result = QMessageBox.question("quit.question", "Installer", "Do you want to quit the installer?",
                                      QMessageBox.Yes | QMessageBox.No);
    if (result == QMessageBox.Yes) {
       // ...
    }
    \endcode

    \section2 Buttons

    QMessageBox defines a list of common buttons:
    \list
    \li QMessageBox.Ok
    \li QMessageBox.Open
    \li QMessageBox.Save
    \li QMessageBox.Cancel
    \li QMessageBox.Close
    \li QMessageBox.Discard
    \li QMessageBox.Apply
    \li QMessageBox.Reset
    \li QMessageBox.RestoreDefaults
    \li QMessageBox.Help
    \li QMessageBox.SaveAll
    \li QMessageBox.Yes
    \li QMessageBox.YesToAll
    \li QMessageBox.No
    \li QMessageBox.NoToAll
    \li QMessageBox.Abort
    \li QMessageBox.Retry
    \li QMessageBox.Ignore
    \li QMessageBox.NoButton
    \endlist

    \section2 Scripted Installations

    Sometimes it is useful to automatically close message boxes, for example during a scripted
    installation. This can be achieved by calling
    Installer::setMessageBoxAutomaticAnswer, Installer::autoAcceptMessageBoxes,
    Installer::autoRejectMessageBoxes. The \c identifier argument in the method calls
    allows to identify specific message boxes for this purpose.
 */


/*!
    \qmlmethod Button QMessageBox::critical(string identifier, string title, string text,
    Buttons buttons = QMessageBox.Ok, Button button
    = QMessageBox.NoButton)

    Opens a critical message box with the given \a title and \a text.
*/

/*!
    \qmlmethod Button QMessageBox::information(string identifier, string title, string text,
    Buttons buttons = QMessageBox.Ok, Button button
    = QMessageBox.NoButton)

    Opens an information message box with the given \a title and \a text.
*/

/*!
    \qmlmethod Button QMessageBox::question(string identifier, string title, string text,
    Buttons buttons = QMessageBox.Yes | QMessageBox.No, Button button
    = QMessageBox.NoButton)

    Opens a question message box with the given \a title and \a text.
*/

/*!
    \qmlmethod Button QMessageBox::warning(string identifier, string title, string text,
    Buttons buttons = QMessageBox.Ok, Button button
    = QMessageBox.NoButton)

    Opens a warning message box with the given \a title and \a text.
*/

using namespace QInstaller;

// -- MessageBoxHandler

MessageBoxHandler *MessageBoxHandler::m_instance = 0;

MessageBoxHandler::MessageBoxHandler(QObject *parent)
    : QObject(parent)
    , m_defaultAction(MessageBoxHandler::AskUser)
{
}

MessageBoxHandler *MessageBoxHandler::instance()
{
    if (m_instance == 0)
        m_instance = new MessageBoxHandler(qApp);
    return m_instance;
}

QWidget *MessageBoxHandler::currentBestSuitParent()
{
#if QT_VERSION < 0x050000
    if (QApplication::type() == QApplication::Tty)
        return 0;
#else
    if (qobject_cast<QApplication*> (qApp) == 0)
        return 0;
#endif

    if (qApp->activeModalWidget())
        return qApp->activeModalWidget();

    return qApp->activeWindow();
}

QList<QMessageBox::Button> MessageBoxHandler::orderedButtons()
{
    static QList<QMessageBox::Button> buttons;
    if (!buttons.isEmpty())
        return buttons;
    buttons << QMessageBox::YesToAll << QMessageBox::Yes << QMessageBox::Ok << QMessageBox::Apply
        << QMessageBox::SaveAll << QMessageBox::Save <<QMessageBox::Retry << QMessageBox::Ignore
        << QMessageBox::Help << QMessageBox::RestoreDefaults << QMessageBox::Reset << QMessageBox::Open
        << QMessageBox::Cancel << QMessageBox::Close << QMessageBox::Abort << QMessageBox::Discard
        << QMessageBox::No << QMessageBox::NoToAll;
    return buttons;
}

void MessageBoxHandler::setDefaultAction(DefaultAction defaultAction)
{
    if (m_defaultAction == defaultAction)
        return;
    m_defaultAction = defaultAction;

    m_buttonOrder.clear();
    if (m_defaultAction != AskUser) {
        m_buttonOrder = orderedButtons();
    }

    if (m_defaultAction == Reject) {
        // If we want to reject everything, we need the lowest button. For example, if Cancel is existing it
        // could use Cancel, but if Close is existing it will use Close.
        std::reverse(m_buttonOrder.begin(), m_buttonOrder.end());
    }
}

void MessageBoxHandler::setAutomaticAnswer(const QString &identifier, QMessageBox::StandardButton answer)
{
    m_automaticAnswers.insert(identifier, answer);
}

// -- static

QMessageBox::StandardButton MessageBoxHandler::critical(QWidget *parent, const QString &identifier,
    const QString &title, const QString &text, QMessageBox::StandardButtons buttons,
    QMessageBox::StandardButton button)
{
    return instance()->showMessageBox(criticalType, parent, identifier, title, text, buttons, button);
}

QMessageBox::StandardButton MessageBoxHandler::information(QWidget *parent, const QString &identifier,
    const QString &title, const QString &text, QMessageBox::StandardButtons buttons,
    QMessageBox::StandardButton button)
{
    return instance()->showMessageBox(informationType, parent, identifier, title, text, buttons, button);
}

QMessageBox::StandardButton MessageBoxHandler::question(QWidget *parent, const QString &identifier,
    const QString &title, const QString &text, QMessageBox::StandardButtons buttons,
    QMessageBox::StandardButton button)
{
    return instance()->showMessageBox(questionType, parent, identifier, title, text, buttons, button);
}

QMessageBox::StandardButton MessageBoxHandler::warning(QWidget *parent, const QString &identifier,
    const QString &title, const QString &text, QMessageBox::StandardButtons buttons,
    QMessageBox::StandardButton button)
{
    return instance()->showMessageBox(warningType, parent, identifier, title, text, buttons, button);
}

// -- invokable

int MessageBoxHandler::critical(const QString &identifier, const QString &title, const QString &text,
    QMessageBox::StandardButtons buttons, QMessageBox::StandardButton button) const
{
    return showMessageBox(criticalType, currentBestSuitParent(), identifier, title, text, buttons, button);
}

int MessageBoxHandler::information(const QString &identifier, const QString &title, const QString &text,
    QMessageBox::StandardButtons buttons, QMessageBox::StandardButton button) const
{
    return showMessageBox(informationType, currentBestSuitParent(), identifier, title, text, buttons, button);
}

int MessageBoxHandler::question(const QString &identifier, const QString &title, const QString &text,
    QMessageBox::StandardButtons buttons, QMessageBox::StandardButton button) const
{
    return showMessageBox(questionType, currentBestSuitParent(), identifier, title, text, buttons, button);
}

int MessageBoxHandler::warning(const QString &identifier, const QString &title, const QString &text,
    QMessageBox::StandardButtons buttons, QMessageBox::StandardButton button) const
{
    return showMessageBox(warningType, currentBestSuitParent(), identifier, title, text, buttons, button);
}

// -- private

QMessageBox::StandardButton MessageBoxHandler::autoReply(QMessageBox::StandardButtons buttons) const
{
    if (buttons == QMessageBox::NoButton)
        return QMessageBox::NoButton;

    foreach (const QMessageBox::StandardButton &currentButton, m_buttonOrder) {
        if ((buttons & currentButton) != 0)
            return currentButton;
    }
    Q_ASSERT(!"the list must have all possible buttons");
    return QMessageBox::NoButton;
}

static QMessageBox::StandardButton showNewMessageBox(QWidget *parent, QMessageBox::Icon icon,
    const QString &title, const QString &text, QMessageBox::StandardButtons buttons,
    QMessageBox::StandardButton defaultButton)
{
    QMessageBox msgBox(icon, title, text, QMessageBox::NoButton, parent);
    QDialogButtonBox *buttonBox = msgBox.findChild<QDialogButtonBox *>();
    Q_ASSERT(buttonBox != 0);

    uint mask = QMessageBox::FirstButton;
    while (mask <= QMessageBox::LastButton) {
        uint sb = buttons & mask;
        mask <<= 1;
        if (!sb)
            continue;
        QPushButton *button = msgBox.addButton((QMessageBox::StandardButton)sb);
        // Choose the first accept role as the default
        if (msgBox.defaultButton())
            continue;
        if ((defaultButton == QMessageBox::NoButton
            && buttonBox->buttonRole(button) == QDialogButtonBox::AcceptRole)
            || (defaultButton != QMessageBox::NoButton && sb == uint(defaultButton))) {
                msgBox.setDefaultButton(button);
        }
    }
#if defined(Q_OS_MAC)
    msgBox.setWindowModality(Qt::WindowModal);
#endif
    if (msgBox.exec() == -1)
        return QMessageBox::Cancel;
    return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton MessageBoxHandler::showMessageBox(MessageType messageType, QWidget *parent,
    const QString &identifier, const QString &title, const QString &text, QMessageBox::StandardButtons buttons,
    QMessageBox::StandardButton defaultButton) const
{
    static QHash<MessageType, QString> messageTypeHash;
    if (messageTypeHash.isEmpty()) {
        messageTypeHash.insert(criticalType, QLatin1String("critical"));
        messageTypeHash.insert(informationType, QLatin1String("information"));
        messageTypeHash.insert(questionType, QLatin1String("question"));
        messageTypeHash.insert(warningType, QLatin1String("warning"));
    };

    qDebug() << QString::fromLatin1("created %1 message box %2: '%3', %4").arg(messageTypeHash
        .value(messageType),identifier, title, text);

#if QT_VERSION < 0x050000
    if (QApplication::type() == QApplication::Tty)
        return defaultButton;
#else
    if (qobject_cast<QApplication*> (qApp) == 0)
        return defaultButton;
#endif

    if (m_automaticAnswers.contains(identifier))
        return m_automaticAnswers.value(identifier);

    if (m_defaultAction == AskUser) {
        switch (messageType) {
            case criticalType:
                return showNewMessageBox(parent, QMessageBox::Critical, title, text, buttons, defaultButton);
            case informationType:
                return showNewMessageBox(parent, QMessageBox::Information, title, text, buttons, defaultButton);
            case questionType:
                return showNewMessageBox(parent, QMessageBox::Question, title, text, buttons, defaultButton);
            case warningType:
                return showNewMessageBox(parent, QMessageBox::Warning, title, text, buttons, defaultButton);
        }
    } else {
        return autoReply(buttons);
    }

    Q_ASSERT_X(false, Q_FUNC_INFO, "Something went really wrong.");
    return defaultButton;
}