/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Designer of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:GPL-EXCEPT$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
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** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
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** $QT_END_LICENSE$
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****************************************************************************/

#include "previewconfigurationwidget_p.h"
#include "ui_previewconfigurationwidget.h"
#include "previewmanager_p.h"
#include "shared_settings_p.h"

#include <iconloader_p.h>
#include <stylesheeteditor_p.h>

#include <deviceskin.h>

#include <QtDesigner/abstractsettings.h>

#include <QtWidgets/qfiledialog.h>
#include <QtWidgets/qstylefactory.h>
#include <QtWidgets/qfiledialog.h>
#include <QtWidgets/qmessagebox.h>
#include <QtCore/qpair.h>
#include <QtCore/qlist.h>
#include <QtCore/qdebug.h>
#include <QtCore/qfileinfo.h>
#include <QtCore/qshareddata.h>


static const char *skinResourcePathC = ":/skins/";

QT_BEGIN_NAMESPACE

static const char *skinExtensionC = "skin";

// Pair of skin name, path
typedef QPair<QString, QString> SkinNamePath;
using Skins = QList<SkinNamePath>;
enum { SkinComboNoneIndex = 0 };

// find default skins (resources)
static const Skins &defaultSkins() {
    static Skins rc;
    if (rc.isEmpty()) {
        const QString skinPath = QLatin1String(skinResourcePathC);
        QString pattern = QStringLiteral("*.");
        pattern += QLatin1String(skinExtensionC);
        const QDir dir(skinPath, pattern);
        const QFileInfoList list = dir.entryInfoList(QDir::Dirs|QDir::NoDotAndDotDot, QDir::Name);
        if (list.isEmpty())
            return rc;
        const QFileInfoList::const_iterator lcend = list.constEnd();
        for (QFileInfoList::const_iterator it = list.constBegin(); it != lcend; ++it)
            rc.push_back(SkinNamePath(it->baseName(), it->filePath()));
    }
    return rc;
}

namespace qdesigner_internal {

// ------------- PreviewConfigurationWidgetPrivate
class PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate {
public:
    PreviewConfigurationWidgetPrivate(QDesignerFormEditorInterface *core, QGroupBox *g);

    void slotEditAppStyleSheet();
    void slotDeleteSkinEntry();
    void slotSkinChanged(int index);

    void retrieveSettings();
    void storeSettings() const;

    QAbstractButton *appStyleSheetChangeButton() const { return m_ui.m_appStyleSheetChangeButton; }
    QAbstractButton *skinRemoveButton() const { return m_ui.m_skinRemoveButton; }
    QComboBox *skinCombo() const { return m_ui.m_skinCombo; }

    QDesignerFormEditorInterface *m_core;

private:
    PreviewConfiguration previewConfiguration() const;
    void setPreviewConfiguration(const PreviewConfiguration &pc);

    QStringList userSkins() const;
    void addUserSkins(const QStringList &files);
    bool canRemoveSkin(int index) const;
    int browseSkin();

    const QString m_defaultStyle;
    QGroupBox *m_parent;
    Ui::PreviewConfigurationWidget m_ui;

    int m_firstUserSkinIndex;
    int m_browseSkinIndex;
    int m_lastSkinIndex; // required in case browse fails
};

PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::PreviewConfigurationWidgetPrivate(
        QDesignerFormEditorInterface *core, QGroupBox *g) :
    m_core(core),
    m_defaultStyle(PreviewConfigurationWidget::tr("Default")),
    m_parent(g),
    m_firstUserSkinIndex(0),
    m_browseSkinIndex(0),
    m_lastSkinIndex(0)
{
    m_ui.setupUi(g);
    // styles
    m_ui.m_styleCombo->setEditable(false);
    QStringList styleItems(m_defaultStyle);
    styleItems += QStyleFactory::keys();
    m_ui.m_styleCombo->addItems(styleItems);

    // sheet
    m_ui.m_appStyleSheetLineEdit->setTextPropertyValidationMode(qdesigner_internal::ValidationStyleSheet);
    m_ui.m_appStyleSheetClearButton->setIcon(qdesigner_internal::createIconSet(QString::fromUtf8("resetproperty.png")));
    QObject::connect(m_ui.m_appStyleSheetClearButton, &QAbstractButton::clicked,
                     m_ui.m_appStyleSheetLineEdit, &qdesigner_internal::TextPropertyEditor::clear);

    m_ui.m_skinRemoveButton->setIcon(qdesigner_internal::createIconSet(QString::fromUtf8("editdelete.png")));
    // skins: find default skins (resources)
    m_ui.m_skinRemoveButton->setEnabled(false);
    Skins skins = defaultSkins();
    skins.push_front(SkinNamePath(PreviewConfigurationWidget::tr("None"), QString()));

    for (const auto &skin : qAsConst(skins))
        m_ui.m_skinCombo->addItem(skin.first, QVariant(skin.second));
    m_browseSkinIndex = m_firstUserSkinIndex = skins.size();
    m_ui.m_skinCombo->addItem(PreviewConfigurationWidget::tr("Browse..."), QString());

    m_ui.m_skinCombo->setMaxVisibleItems (qMax(15, 2 * m_browseSkinIndex));
    m_ui.m_skinCombo->setEditable(false);

    retrieveSettings();
}

bool PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::canRemoveSkin(int index) const
{
    return index >= m_firstUserSkinIndex && index != m_browseSkinIndex;
}

QStringList PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::userSkins() const
{
    QStringList rc;
    for (int i = m_firstUserSkinIndex; i < m_browseSkinIndex; i++)
        rc.push_back(m_ui.m_skinCombo->itemData(i).toString());
    return rc;
}

void PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::addUserSkins(const QStringList &files)
{
    if (files.isEmpty())
        return;
    const QStringList ::const_iterator fcend = files.constEnd();
    for (QStringList::const_iterator it = files.constBegin(); it != fcend; ++it) {
        const QFileInfo fi(*it);
        if (fi.isDir() && fi.isReadable()) {
            m_ui.m_skinCombo->insertItem(m_browseSkinIndex++, fi.baseName(), QVariant(*it));
        } else {
            qWarning() << "Unable to access the skin directory '" << *it << "'.";
        }
    }
}

PreviewConfiguration PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::previewConfiguration() const
{
    PreviewConfiguration  rc;
    QString style = m_ui.m_styleCombo->currentText();
    if (style == m_defaultStyle)
        style.clear();
    const QString applicationStyleSheet = m_ui.m_appStyleSheetLineEdit->text();
    // Figure out skin. 0 is None by definition..
    const int skinIndex = m_ui.m_skinCombo->currentIndex();
    QString deviceSkin;
    if (skinIndex != SkinComboNoneIndex &&  skinIndex != m_browseSkinIndex)
        deviceSkin = m_ui.m_skinCombo->itemData(skinIndex).toString();

    return PreviewConfiguration(style, applicationStyleSheet, deviceSkin);
}

void PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::setPreviewConfiguration(const PreviewConfiguration &pc)
{
    int styleIndex = m_ui.m_styleCombo->findText(pc.style());
    if (styleIndex == -1)
        styleIndex = m_ui.m_styleCombo->findText(m_defaultStyle);
    m_ui.m_styleCombo->setCurrentIndex(styleIndex);
    m_ui.m_appStyleSheetLineEdit->setText(pc.applicationStyleSheet());
    // find skin by file name. 0 is "none"
    const QString deviceSkin = pc.deviceSkin();
    int skinIndex = deviceSkin.isEmpty() ? 0 : m_ui.m_skinCombo->findData(QVariant(deviceSkin));
    if (skinIndex == -1) {
        qWarning() << "Unable to find skin '" << deviceSkin << "'.";
        skinIndex = 0;
    }
    m_ui.m_skinCombo->setCurrentIndex(skinIndex);
}

void  PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::slotEditAppStyleSheet()
{
    StyleSheetEditorDialog dlg(m_core, m_parent, StyleSheetEditorDialog::ModeGlobal);
    dlg.setText(m_ui.m_appStyleSheetLineEdit->text());
    if (dlg.exec() == QDialog::Accepted)
        m_ui.m_appStyleSheetLineEdit->setText(dlg.text());
}

void  PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::slotDeleteSkinEntry()
{
    const int index = m_ui.m_skinCombo->currentIndex();
    if (canRemoveSkin(index)) {
        m_ui.m_skinCombo->setCurrentIndex(SkinComboNoneIndex);
        m_ui.m_skinCombo->removeItem(index);
        m_browseSkinIndex--;
    }
}

void  PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::slotSkinChanged(int index)
{
    if (index == m_browseSkinIndex) {
        m_ui.m_skinCombo->setCurrentIndex(browseSkin());
    } else {
        m_lastSkinIndex = index;
        m_ui.m_skinRemoveButton->setEnabled(canRemoveSkin(index));
        m_ui.m_skinCombo->setToolTip(index != SkinComboNoneIndex ? m_ui.m_skinCombo->itemData(index).toString() : QString());
    }
}

void PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::retrieveSettings()
{
    QDesignerSharedSettings settings(m_core);
    m_parent->setChecked(settings.isCustomPreviewConfigurationEnabled());
    setPreviewConfiguration(settings.customPreviewConfiguration());
    addUserSkins(settings.userDeviceSkins());
}

void PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::storeSettings() const
{
    QDesignerSharedSettings settings(m_core);
    settings.setCustomPreviewConfigurationEnabled(m_parent->isChecked());
    settings.setCustomPreviewConfiguration(previewConfiguration());
    settings.setUserDeviceSkins(userSkins());
}

int  PreviewConfigurationWidget::PreviewConfigurationWidgetPrivate::browseSkin()
{
    QFileDialog dlg(m_parent);
    dlg.setFileMode(QFileDialog::Directory);
    dlg.setOption(QFileDialog::ShowDirsOnly);
    const QString title = tr("Load Custom Device Skin");
    dlg.setWindowTitle(title);
    dlg.setNameFilter(tr("All QVFB Skins (*.%1)").arg(QLatin1String(skinExtensionC)));

    int rc = m_lastSkinIndex;
    do {
        if (!dlg.exec())
            break;

        const QStringList directories =  dlg.selectedFiles();
        if (directories.size() != 1)
            break;

        // check: 1) name already there
        const QString directory = directories.constFirst();
        const QString name = QFileInfo(directory).baseName();
        const int existingIndex = m_ui.m_skinCombo->findText(name);
        if (existingIndex != -1 && existingIndex != SkinComboNoneIndex &&  existingIndex != m_browseSkinIndex) {
            const QString msgTitle = tr("%1 - Duplicate Skin").arg(title);
            const QString msg = tr("The skin '%1' already exists.").arg(name);
            QMessageBox::information(m_parent, msgTitle, msg);
            break;
        }
        // check: 2) can read
        DeviceSkinParameters parameters;
        QString readError;
        if (parameters.read(directory, DeviceSkinParameters::ReadSizeOnly, &readError)) {
            const QString name = QFileInfo(directory).baseName();
            m_ui.m_skinCombo->insertItem(m_browseSkinIndex, name, QVariant(directory));
            rc = m_browseSkinIndex++;

            break;
        }
        const QString msgTitle = tr("%1 - Error").arg(title);
        const QString msg = tr("%1 is not a valid skin directory:\n%2")
                            .arg(directory, readError);
        QMessageBox::warning (m_parent, msgTitle, msg);
    } while (true);
    return rc;
}

// ------------- PreviewConfigurationWidget
PreviewConfigurationWidget::PreviewConfigurationWidget(QDesignerFormEditorInterface *core,
                                                       QWidget *parent) :
    QGroupBox(parent),
    m_impl(new PreviewConfigurationWidgetPrivate(core, this))
{
    connect(m_impl->appStyleSheetChangeButton(), &QAbstractButton::clicked,
            this, &PreviewConfigurationWidget::slotEditAppStyleSheet);
    connect(m_impl->skinRemoveButton(), &QAbstractButton::clicked,
            this, &PreviewConfigurationWidget::slotDeleteSkinEntry);
    connect(m_impl->skinCombo(), &QComboBox::currentIndexChanged,
            this, &PreviewConfigurationWidget::slotSkinChanged);

    m_impl->retrieveSettings();
}

PreviewConfigurationWidget::~PreviewConfigurationWidget()
{
    delete m_impl;
}

void PreviewConfigurationWidget::saveState()
{
    m_impl->storeSettings();
}

void PreviewConfigurationWidget::slotEditAppStyleSheet()
{
    m_impl->slotEditAppStyleSheet();
}

void PreviewConfigurationWidget::slotDeleteSkinEntry()
{
    m_impl->slotDeleteSkinEntry();
}

void PreviewConfigurationWidget::slotSkinChanged(int index)
{
    m_impl->slotSkinChanged(index);
}

}

QT_END_NAMESPACE