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#include <QtGui>

#include "settingstree.h"

#include "variantdelegate.h"

SettingsTree::SettingsTree(QWidget *parent)

    : QTreeWidget(parent)

{

    setItemDelegate(new VariantDelegate(this));

    QStringList labels;

    labels << tr("Setting") << tr("Type") << tr("Value");

    setHeaderLabels(labels);

    header()->setResizeMode(0, QHeaderView::Stretch);

    header()->setResizeMode(2, QHeaderView::Stretch);

    settings = 0;

    refreshTimer.setInterval(2000);

    autoRefresh = false;

    groupIcon.addPixmap(style()->standardPixmap(QStyle::SP_DirClosedIcon),

                        QIcon::Normal, QIcon::Off);

    groupIcon.addPixmap(style()->standardPixmap(QStyle::SP_DirOpenIcon),

                        QIcon::Normal, QIcon::On);

    keyIcon.addPixmap(style()->standardPixmap(QStyle::SP_FileIcon));

    connect(&refreshTimer, SIGNAL(timeout()), this, SLOT(maybeRefresh()));

}

void SettingsTree::setSettingsObject(QSettings *settings)

{

    delete this->settings;

    this->settings = settings;

    clear();

    if (settings) {

        settings->setParent(this);

        refresh();

        if (autoRefresh)

            refreshTimer.start();

    } else {

        refreshTimer.stop();

    }

}

QSize SettingsTree::sizeHint() const

{

    return QSize(800, 600);

}

void SettingsTree::setAutoRefresh(bool autoRefresh)

{

    this->autoRefresh = autoRefresh;

    if (settings) {

        if (autoRefresh) {

            maybeRefresh();

            refreshTimer.start();

        } else {

            refreshTimer.stop();

        }

    }

}

void SettingsTree::setFallbacksEnabled(bool enabled)

{

    if (settings) {

        settings->setFallbacksEnabled(enabled);

        refresh();

    }

}

void SettingsTree::maybeRefresh()

{

    if (state() != EditingState)

        refresh();

}

void SettingsTree::refresh()

{

    if (!settings)

        return;

    disconnect(this, SIGNAL(itemChanged(QTreeWidgetItem *, int)),

               this, SLOT(updateSetting(QTreeWidgetItem *)));

    settings->sync();

    updateChildItems(0);

    connect(this, SIGNAL(itemChanged(QTreeWidgetItem *, int)),

            this, SLOT(updateSetting(QTreeWidgetItem *)));

}

bool SettingsTree::event(QEvent *event)

{

    if (event->type() == QEvent::WindowActivate) {

        if (isActiveWindow() && autoRefresh)

            maybeRefresh();

    }

    return QTreeWidget::event(event);

}

void SettingsTree::updateSetting(QTreeWidgetItem *item)

{

    QString key = item->text(0);

    QTreeWidgetItem *ancestor = item->parent();

    while (ancestor) {

        key.prepend(ancestor->text(0) + "/");

        ancestor = ancestor->parent();

    }

    settings->setValue(key, item->data(2, Qt::UserRole));

    if (autoRefresh)

        refresh();

}

void SettingsTree::updateChildItems(QTreeWidgetItem *parent)

{

    int dividerIndex = 0;

    foreach (QString group, settings->childGroups()) {

        QTreeWidgetItem *child;

        int childIndex = findChild(parent, group, dividerIndex);

        if (childIndex != -1) {

            child = childAt(parent, childIndex);

            child->setText(1, "");

            child->setText(2, "");

            child->setData(2, Qt::UserRole, QVariant());

            moveItemForward(parent, childIndex, dividerIndex);

        } else {

            child = createItem(group, parent, dividerIndex);

        }

        child->setIcon(0, groupIcon);

        ++dividerIndex;

        settings->beginGroup(group);

        updateChildItems(child);

        settings->endGroup();

    }

    foreach (QString key, settings->childKeys()) {

        QTreeWidgetItem *child;

        int childIndex = findChild(parent, key, 0);

        if (childIndex == -1 || childIndex >= dividerIndex) {

            if (childIndex != -1) {

                child = childAt(parent, childIndex);

                for (int i = 0; i < child->childCount(); ++i)

                    delete childAt(child, i);

                moveItemForward(parent, childIndex, dividerIndex);

            } else {

                child = createItem(key, parent, dividerIndex);

            }

            child->setIcon(0, keyIcon);

            ++dividerIndex;

        } else {

            child = childAt(parent, childIndex);

        }

        QVariant value = settings->value(key);

        if (value.type() == QVariant::Invalid) {

            child->setText(1, "Invalid");

        } else {

            child->setText(1, value.typeName());

        }

        child->setText(2, VariantDelegate::displayText(value));

        child->setData(2, Qt::UserRole, value);

    }

    while (dividerIndex < childCount(parent))

        delete childAt(parent, dividerIndex);

}

QTreeWidgetItem *SettingsTree::createItem(const QString &text,

                                          QTreeWidgetItem *parent, int index)

{

    QTreeWidgetItem *after = 0;

    if (index != 0)

        after = childAt(parent, index - 1);

    QTreeWidgetItem *item;

    if (parent)

        item = new QTreeWidgetItem(parent, after);

    else

        item = new QTreeWidgetItem(this, after);

    item->setText(0, text);

    item->setFlags(item->flags() | Qt::ItemIsEditable);

    return item;

}

QTreeWidgetItem *SettingsTree::childAt(QTreeWidgetItem *parent, int index)

{

    if (parent)

        return parent->child(index);

    else

        return topLevelItem(index);

}

int SettingsTree::childCount(QTreeWidgetItem *parent)

{

    if (parent)

        return parent->childCount();

    else

        return topLevelItemCount();

}

int SettingsTree::findChild(QTreeWidgetItem *parent, const QString &text,

                            int startIndex)

{

    for (int i = startIndex; i < childCount(parent); ++i) {

        if (childAt(parent, i)->text(0) == text)

            return i;

    }

    return -1;

}

void SettingsTree::moveItemForward(QTreeWidgetItem *parent, int oldIndex,

                                   int newIndex)

{

    for (int i = 0; i < oldIndex - newIndex; ++i)

        delete childAt(parent, newIndex);

}