// vim: set tabstop=4 shiftwidth=4 expandtab:
/*
Gwenview: an image viewer
Copyright 2008 Aurélien Gâteau <agateau@kde.org>

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Cambridge, MA 02110-1301, USA.

*/
// Self
#include "gvcore.h"
#include "dialogguard.h"

// Qt
#include <QApplication>
#include <QUrl>
#include <QImageWriter>
#include <QMimeDatabase>
#include <QDebug>

// KDE
#include <QFileDialog>
#include <KColorScheme>
#include <KLocalizedString>
#include <KMessageBox>

// Local
#include <lib/binder.h>
#include <lib/document/documentfactory.h>
#include <lib/document/documentjob.h>
#include <lib/document/savejob.h>
#include <lib/hud/hudbutton.h>
#include <lib/gwenviewconfig.h>
#include <lib/historymodel.h>
#include <lib/hud/hudmessagebubble.h>
#include <lib/mimetypeutils.h>
#include <lib/recentfilesmodel.h>
#include <lib/semanticinfo/semanticinfodirmodel.h>
#include <lib/semanticinfo/sorteddirmodel.h>
#include <lib/transformimageoperation.h>
#include <mainwindow.h>
#include <saveallhelper.h>
#include <viewmainpage.h>

namespace Gwenview
{

struct GvCorePrivate
{
    GvCore* q;
    MainWindow* mMainWindow;
    SortedDirModel* mDirModel;
    HistoryModel* mRecentFoldersModel;
    RecentFilesModel* mRecentFilesModel;
    QPalette mPalettes[4];
    QString mFullScreenPaletteName;

    bool showSaveAsDialog(const QUrl &url, QUrl* outUrl, QByteArray* format)
    {
        DialogGuard<QFileDialog> dialog(mMainWindow);
        dialog->setAcceptMode(QFileDialog::AcceptSave);
        dialog->setWindowTitle(i18nc("@title:window", "Save Image"));
        // Temporary workaround for selectUrl() not setting the
        // initial directory to url (removed in D4193)
        dialog->setDirectoryUrl(url.adjusted(QUrl::RemoveFilename));
        dialog->selectUrl(url);

        QStringList supportedMimetypes;
        for (const QByteArray &mimeName : QImageWriter::supportedMimeTypes()) {
            supportedMimetypes.append(QString::fromLocal8Bit(mimeName));
        }

        dialog->setMimeTypeFilters(supportedMimetypes);
        dialog->selectMimeTypeFilter(MimeTypeUtils::urlMimeType(url));

        // Show dialog
        do {
            if (!dialog->exec()) {
                return false;
            }

            QList<QUrl> files = dialog->selectedUrls();
            if (files.isEmpty()) {
                return false;
            }

            QString filename = files.first().fileName();

            const QMimeType mimeType = QMimeDatabase().mimeTypeForFile(filename, QMimeDatabase::MatchExtension);
            if (mimeType.isValid()) {
                *format = mimeType.preferredSuffix().toLocal8Bit();
                break;
            }
            KMessageBox::sorry(
                mMainWindow,
                i18nc("@info",
                      "Gwenview cannot save images as %1.", QFileInfo(filename).suffix())
            );
        } while (true);

        *outUrl = dialog->selectedUrls().first();
        return true;
    }

    void setupPalettes()
    {
        QPalette pal;
        int value = GwenviewConfig::viewBackgroundValue();
        QColor fgColor = value > 128 ? Qt::black : Qt::white;

        // Normal
        KSharedConfigPtr config = KSharedConfig::openConfig();
        mPalettes[GvCore::NormalPalette] = KColorScheme::createApplicationPalette(config);

        pal = mPalettes[GvCore::NormalPalette];
        pal.setColor(QPalette::Base, QColor::fromHsv(0, 0, value));
        pal.setColor(QPalette::Text, fgColor);
        mPalettes[GvCore::NormalViewPalette] = pal;

        // Fullscreen
        QString name = GwenviewConfig::fullScreenColorScheme();
        if (name.isEmpty()) {
            // Default color scheme
            mFullScreenPaletteName = QStandardPaths::locate(QStandardPaths::AppDataLocation, "color-schemes/fullscreen.colors");
            config = KSharedConfig::openConfig(mFullScreenPaletteName);
        } else if (name.contains('/')) {
            // Full path to a .colors file
            mFullScreenPaletteName = name;
            config = KSharedConfig::openConfig(mFullScreenPaletteName);
        } else {
            // Standard KDE color scheme
            mFullScreenPaletteName = QString("color-schemes/%1.colors").arg(name);
            config = KSharedConfig::openConfig(mFullScreenPaletteName, KConfig::FullConfig, QStandardPaths::AppDataLocation);
        }
        mPalettes[GvCore::FullScreenPalette] = KColorScheme::createApplicationPalette(config);

        // If we are using the default palette, adjust it to match the system color scheme
        if (name.isEmpty()) {
            adjustDefaultFullScreenPalette();
        }

        // FullScreenView has textured background
        pal = mPalettes[GvCore::FullScreenPalette];
        QString path = QStandardPaths::locate(QStandardPaths::AppDataLocation, "images/background.png");
        QPixmap bgTexture(path);
        pal.setBrush(QPalette::Base, bgTexture);
        mPalettes[GvCore::FullScreenViewPalette] = pal;
    }

    void adjustDefaultFullScreenPalette()
    {
        // The Fullscreen palette by default does not use the system color scheme, and therefore uses an 'accent' color
        // of blue. So for every color group/role combination that uses the accent color, we use a muted version of the
        // Normal palette. We also use the normal HighlightedText color so it properly contrasts with Highlight.
        const QPalette normalPal = mPalettes[GvCore::NormalPalette];
        QPalette fullscreenPal = mPalettes[GvCore::FullScreenPalette];

        // Colors from the normal palette (source of the system theme's accent color)
        const QColor normalToolTipBase             = normalPal.color(QPalette::Normal,   QPalette::ToolTipBase);
        const QColor normalToolTipText             = normalPal.color(QPalette::Normal,   QPalette::ToolTipText);
        const QColor normalHighlight               = normalPal.color(QPalette::Normal,   QPalette::Highlight);
        const QColor normalHighlightedText         = normalPal.color(QPalette::Normal,   QPalette::HighlightedText);
        const QColor normalLink                    = normalPal.color(QPalette::Normal,   QPalette::Link);
        const QColor normalActiveToolTipBase       = normalPal.color(QPalette::Active,   QPalette::ToolTipBase);
        const QColor normalActiveToolTipText       = normalPal.color(QPalette::Active,   QPalette::ToolTipText);
        const QColor normalActiveHighlight         = normalPal.color(QPalette::Active,   QPalette::Highlight);
        const QColor normalActiveHighlightedText   = normalPal.color(QPalette::Active,   QPalette::HighlightedText);
        const QColor normalActiveLink              = normalPal.color(QPalette::Active,   QPalette::Link);
        const QColor normalDisabledToolTipBase     = normalPal.color(QPalette::Disabled, QPalette::ToolTipBase);
        const QColor normalDisabledToolTipText     = normalPal.color(QPalette::Disabled, QPalette::ToolTipText);
        // Note: Disabled Highlight missing as they do not use the accent color
        const QColor normalDisabledLink            = normalPal.color(QPalette::Disabled, QPalette::Link);
        const QColor normalInactiveToolTipBase     = normalPal.color(QPalette::Inactive, QPalette::ToolTipBase);
        const QColor normalInactiveToolTipText     = normalPal.color(QPalette::Inactive, QPalette::ToolTipText);
        const QColor normalInactiveHighlight       = normalPal.color(QPalette::Inactive, QPalette::Highlight);
        const QColor normalInactiveHighlightedText = normalPal.color(QPalette::Inactive, QPalette::HighlightedText);
        const QColor normalInactiveLink            = normalPal.color(QPalette::Inactive, QPalette::Link);

        // Colors of the fullscreen palette which we will be modifying
        QColor fullScreenToolTipBase         = fullscreenPal.color(QPalette::Normal,   QPalette::ToolTipBase);
        QColor fullScreenToolTipText         = fullscreenPal.color(QPalette::Normal,   QPalette::ToolTipText);
        QColor fullScreenHighlight           = fullscreenPal.color(QPalette::Normal,   QPalette::Highlight);
        QColor fullScreenLink                = fullscreenPal.color(QPalette::Normal,   QPalette::Link);
        QColor fullScreenActiveToolTipBase   = fullscreenPal.color(QPalette::Active,   QPalette::ToolTipBase);
        QColor fullScreenActiveToolTipText   = fullscreenPal.color(QPalette::Active,   QPalette::ToolTipText);
        QColor fullScreenActiveHighlight     = fullscreenPal.color(QPalette::Active,   QPalette::Highlight);
        QColor fullScreenActiveLink          = fullscreenPal.color(QPalette::Active,   QPalette::Link);
        QColor fullScreenDisabledToolTipBase = fullscreenPal.color(QPalette::Disabled, QPalette::ToolTipBase);
        QColor fullScreenDisabledToolTipText = fullscreenPal.color(QPalette::Disabled, QPalette::ToolTipText);
        QColor fullScreenDisabledLink        = fullscreenPal.color(QPalette::Disabled, QPalette::Link);
        QColor fullScreenInactiveToolTipBase = fullscreenPal.color(QPalette::Inactive, QPalette::ToolTipBase);
        QColor fullScreenInactiveToolTipText = fullscreenPal.color(QPalette::Inactive, QPalette::ToolTipText);
        QColor fullScreenInactiveHighlight   = fullscreenPal.color(QPalette::Inactive, QPalette::Highlight);
        QColor fullScreenInactiveLink        = fullscreenPal.color(QPalette::Inactive, QPalette::Link);

        // Adjust the value of the normal color so it's not too dark/bright, and apply to the respective fullscreen color
        fullScreenToolTipBase        .setHsv(normalToolTipBase.hue(),         normalToolTipBase.saturation(),         (127 + 2 * normalToolTipBase.value()) / 3);
        fullScreenToolTipText        .setHsv(normalToolTipText.hue(),         normalToolTipText.saturation(),         (127 + 2 * normalToolTipText.value()) / 3);
        fullScreenHighlight          .setHsv(normalHighlight.hue(),           normalHighlight.saturation(),           (127 + 2 * normalHighlight.value()) / 3);
        fullScreenLink               .setHsv(normalLink.hue(),                normalLink.saturation(),                (127 + 2 * normalLink.value()) / 3);
        fullScreenActiveToolTipBase  .setHsv(normalActiveToolTipBase.hue(),   normalActiveToolTipBase.saturation(),   (127 + 2 * normalActiveToolTipBase.value()) / 3);
        fullScreenActiveToolTipText  .setHsv(normalActiveToolTipText.hue(),   normalActiveToolTipText.saturation(),   (127 + 2 * normalActiveToolTipText.value()) / 3);
        fullScreenActiveHighlight    .setHsv(normalActiveHighlight.hue(),     normalActiveHighlight.saturation(),     (127 + 2 * normalActiveHighlight.value()) / 3);
        fullScreenActiveLink         .setHsv(normalActiveLink.hue(),          normalActiveLink.saturation(),          (127 + 2 * normalActiveLink.value()) / 3);
        fullScreenDisabledToolTipBase.setHsv(normalDisabledToolTipBase.hue(), normalDisabledToolTipBase.saturation(), (127 + 2 * normalDisabledToolTipBase.value()) / 3);
        fullScreenDisabledToolTipText.setHsv(normalDisabledToolTipText.hue(), normalDisabledToolTipText.saturation(), (127 + 2 * normalDisabledToolTipText.value()) / 3);
        fullScreenDisabledLink       .setHsv(normalDisabledLink.hue(),        normalDisabledLink.saturation(),        (127 + 2 * normalDisabledLink.value()) / 3);
        fullScreenInactiveToolTipBase.setHsv(normalInactiveToolTipBase.hue(), normalInactiveToolTipBase.saturation(), (127 + 2 * normalInactiveToolTipBase.value()) / 3);
        fullScreenInactiveToolTipText.setHsv(normalInactiveToolTipText.hue(), normalInactiveToolTipText.saturation(), (127 + 2 * normalInactiveToolTipText.value()) / 3);
        fullScreenInactiveHighlight  .setHsv(normalInactiveHighlight.hue(),   normalInactiveHighlight.saturation(),   (127 + 2 * normalInactiveHighlight.value()) / 3);
        fullScreenInactiveLink       .setHsv(normalInactiveLink.hue(),        normalInactiveLink.saturation(),        (127 + 2 * normalInactiveLink.value()) / 3);

        // Apply the modified colors to the fullscreen palette
        fullscreenPal.setColor(QPalette::Normal,   QPalette::ToolTipBase, fullScreenToolTipBase);
        fullscreenPal.setColor(QPalette::Normal,   QPalette::ToolTipText, fullScreenToolTipText);
        fullscreenPal.setColor(QPalette::Normal,   QPalette::Highlight,   fullScreenHighlight);
        fullscreenPal.setColor(QPalette::Normal,   QPalette::Link,        fullScreenLink);
        fullscreenPal.setColor(QPalette::Active,   QPalette::ToolTipBase, fullScreenActiveToolTipBase);
        fullscreenPal.setColor(QPalette::Active,   QPalette::ToolTipText, fullScreenActiveToolTipText);
        fullscreenPal.setColor(QPalette::Active,   QPalette::Highlight,   fullScreenActiveHighlight);
        fullscreenPal.setColor(QPalette::Active,   QPalette::Link,        fullScreenActiveLink);
        fullscreenPal.setColor(QPalette::Disabled, QPalette::ToolTipBase, fullScreenDisabledToolTipBase);
        fullscreenPal.setColor(QPalette::Disabled, QPalette::ToolTipText, fullScreenDisabledToolTipText);
        fullscreenPal.setColor(QPalette::Disabled, QPalette::Link,        fullScreenDisabledLink);
        fullscreenPal.setColor(QPalette::Inactive, QPalette::ToolTipBase, fullScreenInactiveToolTipBase);
        fullscreenPal.setColor(QPalette::Inactive, QPalette::ToolTipText, fullScreenInactiveToolTipText);
        fullscreenPal.setColor(QPalette::Inactive, QPalette::Highlight,   fullScreenInactiveHighlight);
        fullscreenPal.setColor(QPalette::Inactive, QPalette::Link,        fullScreenInactiveLink);
        
        // Since we use an adjusted version of the normal highlight color, we need to use the normal version of the
        // text color so it contrasts
        fullscreenPal.setColor(QPalette::Normal,     QPalette::HighlightedText,   normalHighlightedText);
        fullscreenPal.setColor(QPalette::Active,     QPalette::HighlightedText,   normalActiveHighlightedText);
        fullscreenPal.setColor(QPalette::Inactive,   QPalette::HighlightedText,   normalInactiveHighlightedText);

        mPalettes[GvCore::FullScreenPalette] = fullscreenPal;
    }
};

GvCore::GvCore(MainWindow* mainWindow, SortedDirModel* dirModel)
: QObject(mainWindow)
, d(new GvCorePrivate)
{
    d->q = this;
    d->mMainWindow = mainWindow;
    d->mDirModel = dirModel;
    d->mRecentFoldersModel = nullptr;
    d->mRecentFilesModel = nullptr;

    d->setupPalettes();

    connect(GwenviewConfig::self(), SIGNAL(configChanged()),
            SLOT(slotConfigChanged()));
}

GvCore::~GvCore()
{
    delete d;
}

QAbstractItemModel* GvCore::recentFoldersModel() const
{
    if (!d->mRecentFoldersModel) {
        d->mRecentFoldersModel = new HistoryModel(const_cast<GvCore*>(this), QStandardPaths::writableLocation(QStandardPaths::AppLocalDataLocation) + "/recentfolders/");
    }
    return d->mRecentFoldersModel;
}

QAbstractItemModel* GvCore::recentFilesModel() const
{
    if (!d->mRecentFilesModel) {
        d->mRecentFilesModel = new RecentFilesModel(const_cast<GvCore*>(this));
    }
    return d->mRecentFilesModel;
}

AbstractSemanticInfoBackEnd* GvCore::semanticInfoBackEnd() const
{
    return d->mDirModel->semanticInfoBackEnd();
}

SortedDirModel* GvCore::sortedDirModel() const
{
    return d->mDirModel;
}

void GvCore::addUrlToRecentFolders(QUrl url)
{
    if (!GwenviewConfig::historyEnabled()) {
        return;
    }
    if (!url.isValid()) {
        return;
    }

    // For "sftp://localhost", "/" is a different path than "" (bug #312060)
    if (!url.path().isEmpty() && !url.path().endsWith('/')) {
        url.setPath(url.path() + '/');
    }

    recentFoldersModel();
    d->mRecentFoldersModel->addUrl(url);
}

void GvCore::addUrlToRecentFiles(const QUrl &url)
{
    if (!GwenviewConfig::historyEnabled()) {
        return;
    }
    recentFilesModel();
    d->mRecentFilesModel->addUrl(url);
}

void GvCore::saveAll()
{
    SaveAllHelper helper(d->mMainWindow);
    helper.save();
}

void GvCore::save(const QUrl &url)
{
    Document::Ptr doc = DocumentFactory::instance()->load(url);
    QByteArray format = doc->format();
    const QByteArrayList availableTypes = QImageWriter::supportedImageFormats();
    if (availableTypes.contains(format)) {
        DocumentJob* job = doc->save(url, format);
        connect(job, SIGNAL(result(KJob*)), SLOT(slotSaveResult(KJob*)));
    } else {
        // We don't know how to save in 'format', ask the user for a format we can
        // write to.
        KGuiItem saveUsingAnotherFormat = KStandardGuiItem::saveAs();
        saveUsingAnotherFormat.setText(i18n("Save using another format"));
        int result = KMessageBox::warningContinueCancel(
                         d->mMainWindow,
                         i18n("Gwenview cannot save images in '%1' format.", QString(format)),
                         QString() /* caption */,
                         saveUsingAnotherFormat
                     );
        if (result == KMessageBox::Continue) {
            saveAs(url);
        }
    }
}

void GvCore::saveAs(const QUrl &url)
{
    QByteArray format;
    QUrl saveAsUrl;
    if (!d->showSaveAsDialog(url, &saveAsUrl, &format)) {
        return;
    }

    // Start save
    Document::Ptr doc = DocumentFactory::instance()->load(url);
    KJob* job = doc->save(saveAsUrl, format.data());
    if (!job) {
        const QString name = saveAsUrl.fileName().isEmpty() ? saveAsUrl.toDisplayString() : saveAsUrl.fileName();
        const QString msg = xi18nc("@info", "<emphasis strong='true'>Saving <filename>%1</filename> failed:</emphasis><nl />%2",
                                   name, doc->errorString());
        KMessageBox::sorry(QApplication::activeWindow(), msg);
    } else {
        connect(job, SIGNAL(result(KJob*)), SLOT(slotSaveResult(KJob*)));
    }
}

static void applyTransform(const QUrl &url, Orientation orientation)
{
    TransformImageOperation* op = new TransformImageOperation(orientation);
    Document::Ptr doc = DocumentFactory::instance()->load(url);
    op->applyToDocument(doc);
}

void GvCore::slotSaveResult(KJob* _job)
{
    SaveJob* job = static_cast<SaveJob*>(_job);
    QUrl oldUrl = job->oldUrl();
    QUrl newUrl = job->newUrl();

    if (job->error()) {
        QString name = newUrl.fileName().isEmpty() ? newUrl.toDisplayString() : newUrl.fileName();
        const QString msg = xi18nc("@info", "<emphasis strong='true'>Saving <filename>%1</filename> failed:</emphasis><nl />%2",
                                   name, kxi18n(qPrintable(job->errorString())));

        int result = KMessageBox::warningContinueCancel(
                         d->mMainWindow, msg,
                         QString() /* caption */,
                         KStandardGuiItem::saveAs());

        if (result == KMessageBox::Continue) {
            saveAs(oldUrl);
        }
        return;
    }

    if (oldUrl != newUrl) {
        d->mMainWindow->goToUrl(newUrl);

        ViewMainPage* page = d->mMainWindow->viewMainPage();
        if (page->isVisible()) {
            HudMessageBubble* bubble = new HudMessageBubble();
            bubble->setText(i18n("You are now viewing the new document."));
            KGuiItem item = KStandardGuiItem::back();
            item.setText(i18n("Go back to the original"));
            HudButton* button = bubble->addButton(item);

            BinderRef<MainWindow, QUrl>::bind(button, SIGNAL(clicked()), d->mMainWindow, &MainWindow::goToUrl, oldUrl);
            connect(button, SIGNAL(clicked()),
                bubble, SLOT(deleteLater()));

            page->showMessageWidget(bubble);
        }
    }
}

void GvCore::rotateLeft(const QUrl &url)
{
    applyTransform(url, ROT_270);
}

void GvCore::rotateRight(const QUrl &url)
{
    applyTransform(url, ROT_90);
}

void GvCore::setRating(const QUrl &url, int rating)
{
    QModelIndex index = d->mDirModel->indexForUrl(url);
    if (!index.isValid()) {
        qWarning() << "invalid index!";
        return;
    }
    d->mDirModel->setData(index, rating, SemanticInfoDirModel::RatingRole);
}

static void clearModel(QAbstractItemModel* model)
{
    model->removeRows(0, model->rowCount());
}

void GvCore::clearRecentFilesAndFolders() {
    clearModel(recentFilesModel());
    clearModel(recentFoldersModel());
}

void GvCore::slotConfigChanged()
{
    if (!GwenviewConfig::historyEnabled()) {
        clearRecentFilesAndFolders();
    }
    d->setupPalettes();
}

QPalette GvCore::palette(GvCore::PaletteType type) const
{
    return d->mPalettes[type];
}

QString GvCore::fullScreenPaletteName() const
{
    return d->mFullScreenPaletteName;
}

} // namespace
