/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the Qt Quick Controls module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL3$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see http://www.qt.io/terms-conditions. For further
** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPLv3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or later as published by the Free
** Software Foundation and appearing in the file LICENSE.GPL included in
** the packaging of this file. Please review the following information to
** ensure the GNU General Public License version 2.0 requirements will be
** met: http://www.gnu.org/licenses/gpl-2.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qquickstyle_p.h"
#include "qquickstyle_p_p.h"
#include "qquickstylable_p.h"

#include <QtCore/qfile.h>
#include <QtCore/qjsondocument.h>
#include <QtCore/qjsonobject.h>
#include <QtCore/qjsonvalue.h>
#include <QtCore/qdebug.h>
#include <QtQml/qqmlengine.h>
#include <QtQuick/qquickitem.h>
#include <QtQuick/qquickwindow.h>

QT_BEGIN_NAMESPACE

/*!
    \qmltype Style
    \inherits QtObject
    \instantiates QQuickStyle
    \inqmlmodule QtQuick.Controls
    \ingroup utilities
    \brief A style interface.

    TODO
*/

/*!
    \qmlproperty color QtQuickControls2::Style::accentColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::backgroundColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::focusColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::frameColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::pressColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::selectedTextColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::selectionColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::shadowColor
*/

/*!
    \qmlproperty color QtQuickControls2::Style::textColor
*/

/*!
    \qmlproperty int QtQuickControls2::Style::padding
*/

/*!
    \qmlproperty int QtQuickControls2::Style::roundness
*/

/*!
    \qmlproperty int QtQuickControls2::Style::spacing
*/

/*!
    \qmlproperty real QtQuickControls2::Style::disabledOpacity
*/

QQuickStyle *QQuickStylePrivate::resolve(QQuickItem *item, QQuickStyle *res)
{
    QQuickStylable *stylable = qobject_cast<QQuickStylable *>(item);
    Q_ASSERT(stylable);

    if (!res && stylable->hasStyle())
        return stylable->style();

    // lookup parent style
    if (!res) {
        QQuickItem *parent = item->parentItem();
        while (!res && parent) {
            QQuickStylable *stylable = qobject_cast<QQuickStylable *>(parent);
            if (stylable && stylable->hasStyle())
                res = stylable->style();
            parent = parent->parentItem();
        }
    }

    // fallback to window or global style
    if (!res) {
        QQuickStylable *window = qobject_cast<QQuickStylable *>(item->window());
        if (window)
            res = window->style();
        if (!res)
            res = QQuickStyle::instance(qmlEngine(item));
    }

    return res;
}

static QColor readColorValue(const QJsonValue &value, const QColor &defaultValue)
{
    if (value.isString())
        return QColor(value.toString());
    return QColor::fromRgba(value.toInt(defaultValue.rgba()));
}

static double readNumberValue(const QJsonValue &value, double defaultValue)
{
    return value.toDouble(defaultValue);
}

QQuickStyle::QQuickStyle(QObject *parent) : QObject(parent)
{
    QJsonDocument doc;

    QFile file(QStringLiteral(":/qtquickcontrols/style.json"));
    if (!file.open(QFile::ReadOnly | QFile::Text)) {
        qDebug() << file.error();
        qWarning() << "QQuickStyle: failed to open ':/qtquickcontrols/style.json': " << qPrintable(file.errorString());
    } else {
        QJsonParseError error;
        doc = QJsonDocument::fromJson(file.readAll(), &error);
        if (error.error != QJsonParseError::NoError)
            qWarning() << "QQuickStyle: failed to parse ':/qtquickcontrols/style.json': " << qPrintable(error.errorString());
    }

    QJsonObject style = doc.object();
    accentColor = readColorValue(style.value(QStringLiteral("accentColor")), QColor("#7bc258"));
    backgroundColor = readColorValue(style.value(QStringLiteral("backgroundColor")), QColor("#ffffff"));
    baseColor = readColorValue(style.value(QStringLiteral("baseColor")), QColor("#eeeeee"));
    focusColor = readColorValue(style.value(QStringLiteral("focusColor")), QColor("#45a7d7"));
    frameColor = readColorValue(style.value(QStringLiteral("frameColor")), QColor("#bdbebf"));
    pressColor = readColorValue(style.value(QStringLiteral("pressColor")), QColor("#33333333"));
    selectedTextColor = readColorValue(style.value(QStringLiteral("selectedTextColor")), QColor("#ffffff"));
    selectionColor = readColorValue(style.value(QStringLiteral("selectionColor")), QColor("#45a7d7"));
    shadowColor = readColorValue(style.value(QStringLiteral("shadowColor")), QColor("#28282a"));
    textColor = readColorValue(style.value(QStringLiteral("textColor")), QColor("#26282a"));
    padding = readNumberValue(style.value(QStringLiteral("padding")), 6);
    roundness = readNumberValue(style.value(QStringLiteral("roundness")), 3);
    spacing = readNumberValue(style.value(QStringLiteral("spacing")), 6);
    disabledOpacity = readNumberValue(style.value(QStringLiteral("disabledOpacity")), 0.3);
}

QQuickStyle *QQuickStyle::instance(QQmlEngine *engine)
{
    static QHash<QQmlEngine *, QQuickStyle *> styles;
    QHash<QQmlEngine *, QQuickStyle *>::iterator it = styles.find(engine);
    if (it == styles.end())
        it = styles.insert(engine, new QQuickStyle(engine));
    return it.value();
}

QQuickStyle *QQuickStyle::qmlAttachedProperties(QObject *object)
{
    return instance(qmlEngine(object));
}

QT_END_NAMESPACE