// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0

#include "qdesigner_widgetbox_p.h"
#include "qdesigner_utils_p.h"

#include <QtDesigner/private/ui4_p.h>

#include <QtCore/qregularexpression.h>
#include <QtCore/qdebug.h>
#include <QtCore/qxmlstream.h>
#include <QtCore/qshareddata.h>

QT_BEGIN_NAMESPACE

using namespace Qt::StringLiterals;

class QDesignerWidgetBoxWidgetData : public QSharedData
{
public:
    QDesignerWidgetBoxWidgetData(const QString &aname, const QString &xml,
                                 const QString &icon_name,
                                 QDesignerWidgetBoxInterface::Widget::Type atype);
    QString m_name;
    QString m_xml;
    QString m_icon_name;
    QDesignerWidgetBoxInterface::Widget::Type m_type;
};

QDesignerWidgetBoxWidgetData::QDesignerWidgetBoxWidgetData(const QString &aname,
                                                           const QString &xml,
                                                           const QString &icon_name,
                                                           QDesignerWidgetBoxInterface::Widget::Type atype) :
    m_name(aname), m_xml(xml), m_icon_name(icon_name), m_type(atype)
{
}

QDesignerWidgetBoxInterface::Widget::Widget(const QString &aname, const QString &xml,
                                            const QString &icon_name, Type atype) :
    m_data(new QDesignerWidgetBoxWidgetData(aname, xml, icon_name, atype))
{
}

QDesignerWidgetBoxInterface::Widget::~Widget() = default;

QDesignerWidgetBoxInterface::Widget::Widget(const Widget &w) :
    m_data(w.m_data)
{
}

QDesignerWidgetBoxInterface::Widget &QDesignerWidgetBoxInterface::Widget::operator=(const Widget &rhs)
{
    if (this != &rhs) {
        m_data = rhs.m_data;
    }
    return *this;
}

QString QDesignerWidgetBoxInterface::Widget::name() const
{
    return m_data->m_name;
}

void QDesignerWidgetBoxInterface::Widget::setName(const QString &aname)
{
    if (m_data->m_name != aname)
        m_data->m_name = aname;
}

QString QDesignerWidgetBoxInterface::Widget::domXml() const
{
    return m_data->m_xml;
}

void QDesignerWidgetBoxInterface::Widget::setDomXml(const QString &xml)
{
    if (m_data->m_xml != xml)
        m_data->m_xml = xml;
}

QString QDesignerWidgetBoxInterface::Widget::iconName() const
{
    return m_data->m_icon_name;
}

void QDesignerWidgetBoxInterface::Widget::setIconName(const QString &icon_name)
{
    if (m_data->m_icon_name != icon_name)
        m_data->m_icon_name = icon_name;
}

QDesignerWidgetBoxInterface::Widget::Type QDesignerWidgetBoxInterface::Widget::type() const
{
    return m_data->m_type;
}

void QDesignerWidgetBoxInterface::Widget::setType(Type atype)
{
    if (m_data->m_type != atype)
        m_data->m_type = atype;
}

bool QDesignerWidgetBoxInterface::Widget::isNull() const
{
    return m_data->m_name.isEmpty();
}

namespace qdesigner_internal {
QDesignerWidgetBox::QDesignerWidgetBox(QWidget *parent, Qt::WindowFlags flags)
    : QDesignerWidgetBoxInterface(parent, flags)
{

}

QDesignerWidgetBox::LoadMode QDesignerWidgetBox::loadMode() const
{
    return m_loadMode;
}

void QDesignerWidgetBox::setLoadMode(LoadMode lm)
{
     m_loadMode = lm;
}

// Convenience to find a widget by class name
bool QDesignerWidgetBox::findWidget(const QDesignerWidgetBoxInterface *wbox,
                                    const QString &className,
                                    const QString &category,
                                    Widget *widgetData)
{
    // Note that entry names do not necessarily match the class name
    // (at least, not for the standard widgets), so,
    // look in the XML for the class name of the first widget to appear
    QString pattern = QStringLiteral("^<widget\\s+class\\s*=\\s*\"");
    pattern += className;
    pattern += QStringLiteral("\".*$");
    const QRegularExpression regexp(pattern);
    Q_ASSERT(regexp.isValid());
    const int catCount = wbox->categoryCount();
    for (int c = 0; c < catCount; c++) {
        const Category cat = wbox->category(c);
        if (category.isEmpty() || cat.name() == category) {
            const int widgetCount =  cat.widgetCount();
            for (int w = 0; w < widgetCount; w++) {
                const Widget widget = cat.widget(w);
                QString xml = widget.domXml(); // Erase the <ui> tag that can be present starting from 4.4
                const auto widgetTagIndex = xml.indexOf("<widget"_L1);
                if (widgetTagIndex != -1) {
                    xml.remove(0, widgetTagIndex);
                    if (regexp.match(xml).hasMatch()) {
                        *widgetData = widget;
                        return true;
                    }
                }
            }
        }
    }
    return false;
}

// Convenience to create a Dom Widget from widget box xml code.
DomUI *QDesignerWidgetBox::xmlToUi(const QString &name, const QString &xml, bool insertFakeTopLevel,
                                   QString *errorMessage)
{
    QXmlStreamReader reader(xml);
    DomUI *ui = nullptr;

    // The xml description must either contain a root element "ui" with a child element "widget"
    // or "widget" as the root element (4.3 legacy)

    while (!reader.atEnd()) {
        if (reader.readNext() == QXmlStreamReader::StartElement) {
            const auto name = reader.name();
            if (ui) {
                reader.raiseError(tr("Unexpected element <%1>").arg(name.toString()));
                continue;
            }

            if (name.compare("widget"_L1, Qt::CaseInsensitive) == 0) { // 4.3 legacy, wrap into DomUI
                ui = new DomUI;
                DomWidget *widget = new DomWidget;
                widget->read(reader);
                ui->setElementWidget(widget);
            } else if (name.compare("ui"_L1, Qt::CaseInsensitive) == 0) { // 4.4
                ui = new DomUI;
                ui->read(reader);
            } else {
                reader.raiseError(tr("Unexpected element <%1>").arg(name.toString()));
            }
        }
   }

    if (reader.hasError()) {
        delete ui;
        *errorMessage = tr("A parse error occurred at line %1, column %2 of the XML code "
                           "specified for the widget %3: %4\n%5")
                           .arg(reader.lineNumber()).arg(reader.columnNumber())
                           .arg(name, reader.errorString(), xml);
        return nullptr;
    }

    if (!ui || !ui->elementWidget()) {
        delete ui;
        *errorMessage = tr("The XML code specified for the widget %1 does not contain "
                           "any widget elements.\n%2").arg(name, xml);
        return nullptr;
    }

    if (insertFakeTopLevel)  {
        DomWidget *fakeTopLevel = new DomWidget;
        fakeTopLevel->setAttributeClass(u"QWidget"_s);
        QList<DomWidget *> children;
        children.push_back(ui->takeElementWidget());
        fakeTopLevel->setElementWidget(children);
        ui->setElementWidget(fakeTopLevel);
    }

    return ui;
}

// Convenience to create a Dom Widget from widget box xml code.
DomUI *QDesignerWidgetBox::xmlToUi(const QString &name, const QString &xml, bool insertFakeTopLevel)
{
    QString errorMessage;
    DomUI *rc = xmlToUi(name, xml, insertFakeTopLevel, &errorMessage);
    if (!rc)
        qdesigner_internal::designerWarning(errorMessage);
    return rc;
}

}  // namespace qdesigner_internal

QT_END_NAMESPACE