/*
    Copyright (c) 2007 Volker Krause <vkrause@kde.org>

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

    This library 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 Library General Public
    License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to the
    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301, USA.
*/

#include "akonadi_serializer_kcalcore.h"

#include <AkonadiCore/abstractdifferencesreporter.h>
#include <AkonadiCore/item.h>
#include <AkonadiCore/collection.h>

#include <KCalCore/Event>
#include <KCalCore/Todo>

#include <KCalUtils/Stringify>

#include <KLocalizedString>

#include <QDate>
#include <qplugin.h>
#include <QDebug>

using namespace KCalCore;
using namespace KCalUtils;
using namespace Akonadi;

SerializerPluginKCalCore::SerializerPluginKCalCore()
{
}

//// ItemSerializerPlugin interface

bool SerializerPluginKCalCore::deserialize(Item &item, const QByteArray &label, QIODevice &data, int version)
{
    Q_UNUSED(version);

    if (label != Item::FullPayload) {
        return false;
    }

    qint32 type;
    quint32 magic, incidenceVersion;
    QDataStream input(&data);
    input >> magic;
    input >> incidenceVersion;
    input >> type;
    data.seek(0);

    Incidence::Ptr incidence;

    if (magic == IncidenceBase::magicSerializationIdentifier()) {
        IncidenceBase::Ptr base;
        switch (static_cast<KCalCore::Incidence::IncidenceType>(type)) {
        case KCalCore::Incidence::TypeEvent:
            base = Event::Ptr(new Event());
            break;
        case KCalCore::Incidence::TypeTodo:
            base = Todo::Ptr(new Todo());
            break;
        case KCalCore::Incidence::TypeJournal:
            base = Journal::Ptr(new Journal());
            break;
        default:
            break;
        }
        input >> base;
        incidence = base.staticCast<KCalCore::Incidence>();
    } else {
        // Use the old format
        incidence = mFormat.readIncidence(data.readAll());
    }

    if (!incidence) {
        qWarning() << "Failed to parse incidence! Item id = " << item.id()
                   << "Storage collection id " << item.storageCollectionId()
                   << "parentCollectionId = " << item.parentCollection().id();
        data.seek(0);
        qWarning() << QString::fromUtf8(data.readAll());
        return false;
    }

    item.setPayload(incidence);
    return true;
}

void SerializerPluginKCalCore::serialize(const Item &item, const QByteArray &label, QIODevice &data, int &version)
{
    Q_UNUSED(version);

    if (label != Item::FullPayload || !item.hasPayload<Incidence::Ptr>()) {
        return;
    }
    Incidence::Ptr i = item.payload<Incidence::Ptr>();

    // Using an env variable for now while testing
    if (qgetenv("KCALCORE_BINARY_SERIALIZER") == QByteArray("1")) {
        QDataStream output(&data);
        IncidenceBase::Ptr base = i;
        output << base;
    } else {
        // ### I guess this can be done without hardcoding stuff
        data.write("BEGIN:VCALENDAR\nPRODID:-//K Desktop Environment//NONSGML libkcal 4.3//EN\nVERSION:2.0\nX-KDE-ICAL-IMPLEMENTATION-VERSION:1.0\n");
        data.write(mFormat.toRawString(i));
        data.write("\nEND:VCALENDAR");
    }
}

//// DifferencesAlgorithmInterface

static bool compareString(const QString &left, const QString &right)
{
    if (left.isEmpty() && right.isEmpty()) {
        return true;
    } else {
        return left == right;
    }
}

static QString toString(const Attendee::Ptr &attendee)
{
    return attendee->name() + QLatin1Char('<') + attendee->email() + QLatin1Char('>');
}

static QString toString(const Alarm::Ptr &)
{
    return QString();
}

static QString toString(const Attachment::Ptr &)
{
    return QString();
}

static QString toString(const QDate &date)
{
    return date.toString();
}

static QString toString(const QDateTime &dateTime)
{
    return dateTime.toString();
}

static QString toString(const QString &str)
{
    return str;
}

static QString toString(bool value)
{
    if (value) {
        return i18n("Yes");
    } else {
        return i18n("No");
    }
}

template<class C>
static void compareList(AbstractDifferencesReporter *reporter, const QString &id, const C &left, const C &right)
{
    for (typename C::const_iterator it = left.begin(), end = left.end(); it != end; ++it) {
        if (!right.contains(*it)) {
            reporter->addProperty(AbstractDifferencesReporter::AdditionalLeftMode, id, toString(*it), QString());
        }
    }

    for (typename C::const_iterator it = right.begin(), end = right.end(); it != end; ++it) {
        if (!left.contains(*it)) {
            reporter->addProperty(AbstractDifferencesReporter::AdditionalRightMode, id, QString(), toString(*it));
        }
    }
}

static void compareIncidenceBase(AbstractDifferencesReporter *reporter, const IncidenceBase::Ptr &left, const IncidenceBase::Ptr &right)
{
    compareList(reporter, i18n("Attendees"), left->attendees(), right->attendees());

    if (!compareString(left->organizer()->fullName(), right->organizer()->fullName())) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Organizer"),
                              left->organizer()->fullName(), right->organizer()->fullName());
    }

    if (!compareString(left->uid(), right->uid())) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("UID"),
                              left->uid(), right->uid());
    }

    if (left->allDay() != right->allDay()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Is all-day"),
                              toString(left->allDay()), toString(right->allDay()));
    }

    if (left->hasDuration() != right->hasDuration()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Has duration"),
                              toString(left->hasDuration()), toString(right->hasDuration()));
    }

    if (left->duration() != right->duration()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Duration"),
                              QString::number(left->duration().asSeconds()), QString::number(right->duration().asSeconds()));
    }
}

static void compareIncidence(AbstractDifferencesReporter *reporter, const Incidence::Ptr &left, const Incidence::Ptr &right)
{
    if (!compareString(left->description(), right->description())) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Description"),
                              left->description(), right->description());
    }

    if (!compareString(left->summary(), right->summary())) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Summary"),
                              left->summary(), right->summary());
    }

    if (left->status() != right->status()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Status"),
                              Stringify::incidenceStatus(left), Stringify::incidenceStatus(right));
    }

    if (left->secrecy() != right->secrecy()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Secrecy"),
                              toString(left->secrecy()), toString(right->secrecy()));
    }

    if (left->priority() != right->priority()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Priority"),
                              toString(left->priority()), toString(right->priority()));
    }

    if (!compareString(left->location(), right->location())) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Location"),
                              left->location(), right->location());
    }

    compareList(reporter, i18n("Categories"), left->categories(), right->categories());
    compareList(reporter, i18n("Alarms"), left->alarms(), right->alarms());
    compareList(reporter, i18n("Resources"), left->resources(), right->resources());
    compareList(reporter, i18n("Attachments"), left->attachments(), right->attachments());
    compareList(reporter, i18n("Exception Dates"), left->recurrence()->exDates(), right->recurrence()->exDates());
    compareList(reporter, i18n("Exception Times"), left->recurrence()->exDateTimes(), right->recurrence()->exDateTimes());
    // TODO: recurrence dates and date/times, exrules, rrules

    if (left->created() != right->created()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode,
                              i18n("Created"), left->created().toString(), right->created().toString());
    }

    if (!compareString(left->relatedTo(), right->relatedTo())) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode,
                              i18n("Related Uid"), left->relatedTo(), right->relatedTo());
    }
}

static void compareEvent(AbstractDifferencesReporter *reporter, const Event::Ptr &left, const Event::Ptr &right)
{
    if (left->dtStart() != right->dtStart()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Start time"),
                              left->dtStart().toString(), right->dtStart().toString());
    }

    if (left->hasEndDate() != right->hasEndDate()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Has End Date"),
                              toString(left->hasEndDate()), toString(right->hasEndDate()));
    }

    if (left->dtEnd() != right->dtEnd()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("End Date"),
                              left->dtEnd().toString(), right->dtEnd().toString());
    }

    // TODO: check transparency
}

static void compareTodo(AbstractDifferencesReporter *reporter, const Todo::Ptr &left, const Todo::Ptr &right)
{
    if (left->hasStartDate() != right->hasStartDate()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Has Start Date"),
                              toString(left->hasStartDate()), toString(right->hasStartDate()));
    }

    if (left->hasDueDate() != right->hasDueDate()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Has Due Date"),
                              toString(left->hasDueDate()), toString(right->hasDueDate()));
    }

    if (left->dtDue() != right->dtDue()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Due Date"),
                              left->dtDue().toString(), right->dtDue().toString());
    }

    if (left->hasCompletedDate() != right->hasCompletedDate()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Has Complete Date"),
                              toString(left->hasCompletedDate()), toString(right->hasCompletedDate()));
    }

    if (left->percentComplete() != right->percentComplete()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Complete"),
                              QString::number(left->percentComplete()), QString::number(right->percentComplete()));
    }

    if (left->completed() != right->completed()) {
        reporter->addProperty(AbstractDifferencesReporter::ConflictMode, i18n("Completed"),
                              toString(left->completed()), toString(right->completed()));
    }
}

void SerializerPluginKCalCore::compare(Akonadi::AbstractDifferencesReporter *reporter, const Akonadi::Item &leftItem, const Akonadi::Item &rightItem)
{
    Q_ASSERT(reporter);
    Q_ASSERT(leftItem.hasPayload<Incidence::Ptr>());
    Q_ASSERT(rightItem.hasPayload<Incidence::Ptr>());

    const Incidence::Ptr leftIncidencePtr = leftItem.payload<Incidence::Ptr>();
    const Incidence::Ptr rightIncidencePtr = rightItem.payload<Incidence::Ptr>();

    if (leftIncidencePtr->type() == Incidence::TypeEvent) {
        reporter->setLeftPropertyValueTitle(i18n("Changed Event"));
        reporter->setRightPropertyValueTitle(i18n("Conflicting Event"));
    } else if (leftIncidencePtr->type() == Incidence::TypeTodo) {
        reporter->setLeftPropertyValueTitle(i18n("Changed Todo"));
        reporter->setRightPropertyValueTitle(i18n("Conflicting Todo"));
    }

    compareIncidenceBase(reporter, leftIncidencePtr, rightIncidencePtr);
    compareIncidence(reporter, leftIncidencePtr, rightIncidencePtr);

    const Event::Ptr leftEvent = leftIncidencePtr.dynamicCast<Event>();
    const Event::Ptr rightEvent = rightIncidencePtr.dynamicCast<Event>();
    if (leftEvent && rightEvent) {
        compareEvent(reporter, leftEvent, rightEvent);
    } else {
        const Todo::Ptr leftTodo = leftIncidencePtr.dynamicCast<Todo>();
        const Todo::Ptr rightTodo = rightIncidencePtr.dynamicCast<Todo>();
        if (leftTodo && rightTodo) {
            compareTodo(reporter, leftTodo, rightTodo);
        }
    }
}

//// GidExtractorInterface

QString SerializerPluginKCalCore::extractGid(const Item &item) const
{
    if (!item.hasPayload<Incidence::Ptr>()) {
        return QString();
    }
    return item.payload<Incidence::Ptr>()->instanceIdentifier();
}
