/*
    This file is part of the KDE Libraries
    SPDX-FileCopyrightText: 2006 Tobias Koenig <tokoe@kde.org>

    SPDX-License-Identifier: LGPL-2.0-or-later
*/

#include "kpagewidgetmodel.h"
#include "kpagewidgetmodel_p.h"

#include "loggingcategory.h"

#include <QPointer>
#include <QWidget>

#include <QIcon>

class KPageWidgetItemPrivate
{
public:
    KPageWidgetItemPrivate()
        : checkable(false)
        , checked(false)
        , enabled(true)
        , headerVisible(true)
    {
    }

    ~KPageWidgetItemPrivate()
    {
        delete widget;
        widget = nullptr;
    }

    QString name;
    QString header;
    QIcon icon;
    QPointer<QWidget> widget;
    bool checkable : 1;
    bool checked : 1;
    bool enabled : 1;
    bool headerVisible : 1;
    QList<QAction *> actions;
};

KPageWidgetItem::KPageWidgetItem(QWidget *widget)
    : QObject(nullptr)
    , d(new KPageWidgetItemPrivate)
{
    d->widget = widget;

    // Hide the widget, otherwise when the widget has this KPageView as
    // parent the widget is shown outside the QStackedWidget if the page
    // was not selected ( and reparented ) yet.
    if (d->widget) {
        d->widget->hide();
    }
}

KPageWidgetItem::KPageWidgetItem(QWidget *widget, const QString &name)
    : QObject(nullptr)
    , d(new KPageWidgetItemPrivate)
{
    d->widget = widget;
    d->name = name;

    // Hide the widget, otherwise when the widget has this KPageView as
    // parent the widget is shown outside the QStackedWidget if the page
    // was not selected ( and reparented ) yet.
    if (d->widget) {
        d->widget->hide();
    }
}

KPageWidgetItem::~KPageWidgetItem() = default;

void KPageWidgetItem::setEnabled(bool enabled)
{
    d->enabled = enabled;
    if (d->widget) {
        d->widget->setEnabled(enabled);
    }
    Q_EMIT changed();
}

bool KPageWidgetItem::isEnabled() const
{
    return d->enabled;
}

bool KPageWidgetItem::isHeaderVisible() const
{
    return d->headerVisible;
}

void KPageWidgetItem::setHeaderVisible(bool visible)
{
    d->headerVisible = visible;

    Q_EMIT changed();
}

QWidget *KPageWidgetItem::widget() const
{
    return d->widget;
}

void KPageWidgetItem::setName(const QString &name)
{
    d->name = name;

    Q_EMIT changed();
}

QString KPageWidgetItem::name() const
{
    return d->name;
}

void KPageWidgetItem::setHeader(const QString &header)
{
    d->header = header;

    Q_EMIT changed();
}

QString KPageWidgetItem::header() const
{
    return d->header;
}

void KPageWidgetItem::setIcon(const QIcon &icon)
{
    d->icon = icon;

    Q_EMIT changed();
}

QIcon KPageWidgetItem::icon() const
{
    return d->icon;
}

void KPageWidgetItem::setCheckable(bool checkable)
{
    d->checkable = checkable;

    Q_EMIT changed();
}

bool KPageWidgetItem::isCheckable() const
{
    return d->checkable;
}

void KPageWidgetItem::setChecked(bool checked)
{
    d->checked = checked;

    Q_EMIT toggled(checked);
    Q_EMIT changed();
}

bool KPageWidgetItem::isChecked() const
{
    return d->checked;
}

QList<QAction *> KPageWidgetItem::actions() const
{
    return d->actions;
}

void KPageWidgetItem::setActions(QList<QAction *> actions)
{
    if (d->actions == actions) {
        return;
    }
    d->actions = actions;
    Q_EMIT actionsChanged();
}

PageItem::PageItem(KPageWidgetItem *pageWidgetItem, PageItem *parent)
    : mPageWidgetItem(pageWidgetItem)
    , mParentItem(parent)
{
}

PageItem::~PageItem()
{
    delete mPageWidgetItem;
    mPageWidgetItem = nullptr;

    qDeleteAll(mChildItems);
}

void PageItem::appendChild(PageItem *item)
{
    mChildItems.append(item);
}

void PageItem::insertChild(int row, PageItem *item)
{
    mChildItems.insert(row, item);
}

void PageItem::removeChild(int row)
{
    mChildItems.removeAt(row);
}

PageItem *PageItem::child(int row)
{
    return mChildItems.value(row);
}

int PageItem::childCount() const
{
    return mChildItems.count();
}

int PageItem::columnCount() const
{
    return 1;
}

PageItem *PageItem::parent()
{
    return mParentItem;
}

int PageItem::row() const
{
    if (mParentItem) {
        return mParentItem->mChildItems.indexOf(const_cast<PageItem *>(this));
    }

    return 0;
}

KPageWidgetItem *PageItem::pageWidgetItem() const
{
    return mPageWidgetItem;
}

PageItem *PageItem::findChild(const KPageWidgetItem *item)
{
    if (mPageWidgetItem == item) {
        return this;
    }

    for (int i = 0; i < mChildItems.count(); ++i) {
        PageItem *pageItem = mChildItems[i]->findChild(item);
        if (pageItem) {
            return pageItem;
        }
    }

    return nullptr;
}

void PageItem::dump(int indent)
{
    const QString indentation(indent, QLatin1Char(' '));

    const QString name = (mPageWidgetItem ? mPageWidgetItem->name() : QStringLiteral("root"));
    qCDebug(KWidgetsAddonsLog, "%s (%p)", qPrintable(QString(indentation + name)), (void *)this);
    for (int i = 0; i < mChildItems.count(); ++i) {
        mChildItems[i]->dump(indent + 2);
    }
}

KPageWidgetModel::KPageWidgetModel(QObject *parent)
    : KPageModel(*new KPageWidgetModelPrivate, parent)
{
}

KPageWidgetModel::~KPageWidgetModel()
{
}

int KPageWidgetModel::columnCount(const QModelIndex &) const
{
    return 1;
}

QVariant KPageWidgetModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid()) {
        return QVariant();
    }

    PageItem *item = static_cast<PageItem *>(index.internalPointer());

    if (role == Qt::DisplayRole) {
        return QVariant(item->pageWidgetItem()->name());
    } else if (role == Qt::DecorationRole) {
        return QVariant(item->pageWidgetItem()->icon());
    } else if (role == HeaderRole) {
        return QVariant(item->pageWidgetItem()->header());
    } else if (role == HeaderVisibleRole) {
        return item->pageWidgetItem()->isHeaderVisible();
    } else if (role == WidgetRole) {
        return QVariant::fromValue(item->pageWidgetItem()->widget());
    } else if (role == ActionsRole) {
        return QVariant::fromValue(item->pageWidgetItem()->actions());
    } else if (role == Qt::CheckStateRole) {
        if (item->pageWidgetItem()->isCheckable()) {
            return (item->pageWidgetItem()->isChecked() ? Qt::Checked : Qt::Unchecked);
        } else {
            return QVariant();
        }
    } else {
        return QVariant();
    }
}

bool KPageWidgetModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (!index.isValid()) {
        return false;
    }

    if (role != Qt::CheckStateRole) {
        return false;
    }

    PageItem *item = static_cast<PageItem *>(index.internalPointer());
    if (!item) {
        return false;
    }

    if (!item->pageWidgetItem()->isCheckable()) {
        return false;
    }

    if (value.toInt() == Qt::Checked) {
        item->pageWidgetItem()->setChecked(true);
    } else {
        item->pageWidgetItem()->setChecked(false);
    }

    return true;
}

Qt::ItemFlags KPageWidgetModel::flags(const QModelIndex &index) const
{
    if (!index.isValid()) {
        return Qt::NoItemFlags;
    }

    Qt::ItemFlags flags = Qt::ItemIsSelectable;

    PageItem *item = static_cast<PageItem *>(index.internalPointer());
    if (item->pageWidgetItem()->isCheckable()) {
        flags |= Qt::ItemIsUserCheckable;
    }
    if (item->pageWidgetItem()->isEnabled()) {
        flags |= Qt::ItemIsEnabled;
    }

    return flags;
}

QModelIndex KPageWidgetModel::index(int row, int column, const QModelIndex &parent) const
{
    Q_D(const KPageWidgetModel);

    PageItem *parentItem;

    if (parent.isValid()) {
        parentItem = static_cast<PageItem *>(parent.internalPointer());
    } else {
        parentItem = d->rootItem;
    }

    PageItem *childItem = parentItem->child(row);
    if (childItem) {
        return createIndex(row, column, childItem);
    } else {
        return QModelIndex();
    }
}

QModelIndex KPageWidgetModel::parent(const QModelIndex &index) const
{
    Q_D(const KPageWidgetModel);

    if (!index.isValid()) {
        return QModelIndex();
    }

    PageItem *item = static_cast<PageItem *>(index.internalPointer());
    PageItem *parentItem = item->parent();

    if (parentItem == d->rootItem) {
        return QModelIndex();
    } else {
        return createIndex(parentItem->row(), 0, parentItem);
    }
}

int KPageWidgetModel::rowCount(const QModelIndex &parent) const
{
    Q_D(const KPageWidgetModel);

    PageItem *parentItem;

    if (!parent.isValid()) {
        parentItem = d->rootItem;
    } else {
        parentItem = static_cast<PageItem *>(parent.internalPointer());
    }

    return parentItem->childCount();
}

KPageWidgetItem *KPageWidgetModel::addPage(QWidget *widget, const QString &name)
{
    KPageWidgetItem *item = new KPageWidgetItem(widget, name);

    addPage(item);

    return item;
}

void KPageWidgetModel::addPage(KPageWidgetItem *item)
{
    Q_EMIT layoutAboutToBeChanged();

    Q_D(KPageWidgetModel);
    connect(item, SIGNAL(changed()), this, SLOT(_k_itemChanged()));
    connect(item, SIGNAL(toggled(bool)), this, SLOT(_k_itemToggled(bool)));

    // The row to be inserted
    int row = d->rootItem->childCount();

    beginInsertRows(QModelIndex(), row, row);

    PageItem *pageItem = new PageItem(item, d->rootItem);
    d->rootItem->appendChild(pageItem);

    endInsertRows();

    Q_EMIT layoutChanged();
}

KPageWidgetItem *KPageWidgetModel::insertPage(KPageWidgetItem *before, QWidget *widget, const QString &name)
{
    KPageWidgetItem *item = new KPageWidgetItem(widget, name);

    insertPage(before, item);

    return item;
}

void KPageWidgetModel::insertPage(KPageWidgetItem *before, KPageWidgetItem *item)
{
    Q_D(KPageWidgetModel);

    PageItem *beforePageItem = d->rootItem->findChild(before);
    if (!beforePageItem) {
        qCDebug(KWidgetsAddonsLog, "Invalid KPageWidgetItem passed!");
        return;
    }

    Q_EMIT layoutAboutToBeChanged();

    connect(item, SIGNAL(changed()), this, SLOT(_k_itemChanged()));
    connect(item, SIGNAL(toggled(bool)), this, SLOT(_k_itemToggled(bool)));

    PageItem *parent = beforePageItem->parent();
    // The row to be inserted
    int row = beforePageItem->row();

    QModelIndex index;
    if (parent != d->rootItem) {
        index = createIndex(parent->row(), 0, parent);
    }

    beginInsertRows(index, row, row);

    PageItem *newPageItem = new PageItem(item, parent);
    parent->insertChild(row, newPageItem);

    endInsertRows();

    Q_EMIT layoutChanged();
}

KPageWidgetItem *KPageWidgetModel::addSubPage(KPageWidgetItem *parent, QWidget *widget, const QString &name)
{
    KPageWidgetItem *item = new KPageWidgetItem(widget, name);

    addSubPage(parent, item);

    return item;
}

void KPageWidgetModel::addSubPage(KPageWidgetItem *parent, KPageWidgetItem *item)
{
    Q_D(KPageWidgetModel);

    PageItem *parentPageItem = d->rootItem->findChild(parent);
    if (!parentPageItem) {
        qCDebug(KWidgetsAddonsLog, "Invalid KPageWidgetItem passed!");
        return;
    }

    Q_EMIT layoutAboutToBeChanged();

    connect(item, SIGNAL(changed()), this, SLOT(_k_itemChanged()));
    connect(item, SIGNAL(toggled(bool)), this, SLOT(_k_itemToggled(bool)));

    // The row to be inserted
    int row = parentPageItem->childCount();

    QModelIndex index;
    if (parentPageItem != d->rootItem) {
        index = createIndex(parentPageItem->row(), 0, parentPageItem);
    }

    beginInsertRows(index, row, row);

    PageItem *newPageItem = new PageItem(item, parentPageItem);
    parentPageItem->appendChild(newPageItem);

    endInsertRows();

    Q_EMIT layoutChanged();
}

void KPageWidgetModel::removePage(KPageWidgetItem *item)
{
    if (!item) {
        return;
    }

    Q_D(KPageWidgetModel);

    PageItem *pageItem = d->rootItem->findChild(item);
    if (!pageItem) {
        qCDebug(KWidgetsAddonsLog, "Invalid KPageWidgetItem passed!");
        return;
    }

    Q_EMIT layoutAboutToBeChanged();

    disconnect(item, SIGNAL(changed()), this, SLOT(_k_itemChanged()));
    disconnect(item, SIGNAL(toggled(bool)), this, SLOT(_k_itemToggled(bool)));

    PageItem *parentPageItem = pageItem->parent();
    int row = parentPageItem->row();

    QModelIndex index;
    if (parentPageItem != d->rootItem) {
        index = createIndex(row, 0, parentPageItem);
    }

    beginRemoveRows(index, pageItem->row(), pageItem->row());

    parentPageItem->removeChild(pageItem->row());
    delete pageItem;

    endRemoveRows();

    Q_EMIT layoutChanged();
}

KPageWidgetItem *KPageWidgetModel::item(const QModelIndex &index) const
{
    if (!index.isValid()) {
        return nullptr;
    }

    PageItem *item = static_cast<PageItem *>(index.internalPointer());
    if (!item) {
        return nullptr;
    }

    return item->pageWidgetItem();
}

QModelIndex KPageWidgetModel::index(const KPageWidgetItem *item) const
{
    Q_D(const KPageWidgetModel);

    if (!item) {
        return QModelIndex();
    }

    const PageItem *pageItem = d->rootItem->findChild(item);
    if (!pageItem) {
        return QModelIndex();
    }

    return createIndex(pageItem->row(), 0, (void *)pageItem);
}

#include "moc_kpagewidgetmodel.cpp"