/*
    SPDX-FileCopyrightText: 2007 Tobias Koenig <tokoe@kde.org>

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

#include "generator_plucker.h"

#include <QAbstractTextDocumentLayout>
#include <QFile>
#include <QPainter>
#include <QPrinter>
#include <QTextDocument>

#include <KAboutData>
#include <KLocalizedString>

#include <core/page.h>

OKULAR_EXPORT_PLUGIN(PluckerGenerator, "libokularGenerator_plucker.json")

static void calculateBoundingRect(QTextDocument *document, int startPosition, int endPosition, QRectF &rect)
{
    const QTextBlock startBlock = document->findBlock(startPosition);
    const QRectF startBoundingRect = document->documentLayout()->blockBoundingRect(startBlock);

    const QTextBlock endBlock = document->findBlock(endPosition);
    const QRectF endBoundingRect = document->documentLayout()->blockBoundingRect(endBlock);

    QTextLayout *startLayout = startBlock.layout();
    QTextLayout *endLayout = endBlock.layout();

    int startPos = startPosition - startBlock.position();
    int endPos = endPosition - endBlock.position();
    const QTextLine startLine = startLayout->lineForTextPosition(startPos);
    const QTextLine endLine = endLayout->lineForTextPosition(endPos);

    double x = startBoundingRect.x() + startLine.cursorToX(startPos);
    double y = startBoundingRect.y() + startLine.y();
    double r = endBoundingRect.x() + endLine.cursorToX(endPos);
    double b = endBoundingRect.y() + endLine.y() + endLine.height();

    const QSizeF size = document->size();
    rect = QRectF(x / size.width(), y / size.height(), (r - x) / size.width(), (b - y) / size.height());
}

PluckerGenerator::PluckerGenerator(QObject *parent, const QVariantList &args)
    : Generator(parent, args)
{
}

PluckerGenerator::~PluckerGenerator()
{
}

bool PluckerGenerator::loadDocument(const QString &fileName, QVector<Okular::Page *> &pagesVector)
{
    QUnpluck unpluck;

    if (!unpluck.open(fileName)) {
        return false;
    }

    mPages = unpluck.pages();
    mLinks = unpluck.links();

    const QMap<QString, QString> infos = unpluck.infos();
    QMapIterator<QString, QString> it(infos);
    while (it.hasNext()) {
        it.next();
        if (!it.value().isEmpty()) {
            if (it.key() == QLatin1String("name")) {
                mDocumentInfo.set(QStringLiteral("name"), it.value(), i18n("Name"));
            } else if (it.key() == QLatin1String("title")) {
                mDocumentInfo.set(Okular::DocumentInfo::Title, it.value());
            } else if (it.key() == QLatin1String("author")) {
                mDocumentInfo.set(Okular::DocumentInfo::Author, it.value());
            } else if (it.key() == QLatin1String("time")) {
                mDocumentInfo.set(Okular::DocumentInfo::CreationDate, it.value());
            }
        }
    }

    pagesVector.resize(mPages.count());

    for (int i = 0; i < mPages.count(); ++i) {
        QSizeF size = mPages[i]->size();
        Okular::Page *page = new Okular::Page(i, size.width(), size.height(), Okular::Rotation0);
        pagesVector[i] = page;
    }

    return true;
}

bool PluckerGenerator::doCloseDocument()
{
    mLinkAdded.clear();
    mLinks.clear();

    qDeleteAll(mPages);
    mPages.clear();

    // do not use clear() for the following, otherwise its type is changed
    mDocumentInfo = Okular::DocumentInfo();

    return true;
}

Okular::DocumentInfo PluckerGenerator::generateDocumentInfo(const QSet<Okular::DocumentInfo::Key> & /*keys*/) const
{
    return mDocumentInfo;
}

QImage PluckerGenerator::image(Okular::PixmapRequest *request)
{
    const QSizeF size = mPages[request->pageNumber()]->size();

    QImage image(request->width(), request->height(), QImage::Format_ARGB32_Premultiplied);
    image.fill(Qt::white);

    QPainter p;
    p.begin(&image);

    qreal width = request->width();
    qreal height = request->height();

    p.scale(width / (qreal)size.width(), height / (qreal)size.height());
    mPages[request->pageNumber()]->drawContents(&p);
    p.end();

    if (!mLinkAdded.contains(request->pageNumber())) {
        QList<Okular::ObjectRect *> objects;
        for (int i = 0; i < mLinks.count(); ++i) {
            if (mLinks[i].page == request->pageNumber()) {
                QTextDocument *document = mPages[request->pageNumber()];

                QRectF rect;
                calculateBoundingRect(document, mLinks[i].start, mLinks[i].end, rect);

                objects.append(new Okular::ObjectRect(rect.left(), rect.top(), rect.right(), rect.bottom(), false, Okular::ObjectRect::Action, mLinks[i].link));
            }
        }

        if (!objects.isEmpty()) {
            request->page()->setObjectRects(objects);
        }

        mLinkAdded.insert(request->pageNumber());
    }

    return image;
}

Okular::ExportFormat::List PluckerGenerator::exportFormats() const
{
    static Okular::ExportFormat::List formats;
    if (formats.isEmpty()) {
        formats.append(Okular::ExportFormat::standardFormat(Okular::ExportFormat::PlainText));
    }

    return formats;
}

bool PluckerGenerator::exportTo(const QString &fileName, const Okular::ExportFormat &format)
{
    if (format.mimeType().name() == QLatin1String("text/plain")) {
        QFile file(fileName);
        if (!file.open(QIODevice::WriteOnly)) {
            return false;
        }

        QTextStream out(&file);
        for (int i = 0; i < mPages.count(); ++i) {
            out << mPages[i]->toPlainText();
        }

        return true;
    }

    return false;
}

#include "generator_plucker.moc"