/***************************************************************************
 *   Copyright (C) 2009 by Adam Kidder <thekidder@gmail.com>               *
 *   Copyright (C) 2009 by Peter Penz <peter.penz@gmx.at>                  *
 *                                                                         *
 *   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, Boston, MA 02110-1301 USA            *
 ***************************************************************************/

#include "searchcriterionselector.h"

#define DISABLE_NEPOMUK_LEGACY
#include <nepomuk/comparisonterm.h>
#include <nepomuk/literalterm.h>
#include <nepomuk/query.h>

#include "nie.h"
#include "searchcriterionvalue.h"

#include <Soprano/LiteralValue>
#include <Soprano/Vocabulary/NAO>

#include <QComboBox>
#include <QHBoxLayout>
#include <QList>
#include <QPushButton>

#include <kicon.h>
#include <klocale.h>

SearchCriterionSelector::SearchCriterionSelector(Type type, QWidget* parent) :
    QWidget(parent),
    m_layout(0),
    m_descriptionsBox(0),
    m_comparatorBox(0),
    m_valueWidget(0),
    m_removeButton(0),
    m_descriptions()
{
    m_descriptionsBox = new QComboBox(this);

    m_comparatorBox = new QComboBox(this);
    m_comparatorBox->setSizeAdjustPolicy(QComboBox::AdjustToContents);

    createDescriptions();
    const int index = static_cast<int>(type);
    m_descriptionsBox->setCurrentIndex(index);

    QWidget* filler = new QWidget(this);
    filler->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);

    m_removeButton = new QPushButton(this);
    m_removeButton->setIcon(KIcon("list-remove"));
    m_removeButton->setToolTip(i18nc("@info", "Remove search option"));
    m_removeButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
    connect(m_removeButton, SIGNAL(clicked()), this, SIGNAL(removeCriterion()));

    m_layout = new QHBoxLayout(this);
    m_layout->setMargin(0);
    m_layout->addWidget(m_removeButton);
    m_layout->addWidget(m_descriptionsBox);
    m_layout->addWidget(m_comparatorBox);
    m_layout->addWidget(filler);

    setLayout(m_layout);

    slotDescriptionChanged(index);
    connect(m_descriptionsBox, SIGNAL(currentIndexChanged(int)), this, SLOT(slotDescriptionChanged(int)));
}

SearchCriterionSelector::~SearchCriterionSelector()
{
}

Nepomuk::Query::Term SearchCriterionSelector::queryTerm() const
{
    if (m_valueWidget == 0) {
        return Nepomuk::Query::Term();
    }

    const int descIndex = m_descriptionsBox->currentIndex();
    const SearchCriterionDescription& descr = m_descriptions[descIndex];

    const int compIndex = m_comparatorBox->currentIndex();
    const SearchCriterionDescription::Comparator& comp = descr.comparators()[compIndex];
    if (!comp.isActive) {
        return Nepomuk::Query::Term();
    }

    const Nepomuk::Query::ComparisonTerm term(descr.identifier(),
                                              m_valueWidget->value(),
                                              comp.value);
    return term;
}

SearchCriterionSelector::Type SearchCriterionSelector::type() const
{
    return static_cast<Type>(m_descriptionsBox->currentIndex());
}

void SearchCriterionSelector::slotDescriptionChanged(int index)
{
    if (m_valueWidget != 0) {
        m_valueWidget->hide();
        m_layout->removeWidget(m_valueWidget);
        m_valueWidget = 0;
        // the value widget is obtained by the Search Criterion
        // Selector instance and may not get deleted
    }

    // add comparator items
    disconnect(m_comparatorBox, SIGNAL(currentIndexChanged(int)), this, SLOT(slotComparatorChanged(int)));
    m_comparatorBox->clear();

    const SearchCriterionDescription& description = m_descriptions[index];
    foreach (const SearchCriterionDescription::Comparator& comp, description.comparators()) {
        m_comparatorBox->addItem(comp.name);
    }

    // add value widget
    m_valueWidget = description.valueWidget();
    m_layout->insertWidget(3, m_valueWidget);

    m_comparatorBox->setCurrentIndex(0);
    slotComparatorChanged(0);
    connect(m_comparatorBox, SIGNAL(currentIndexChanged(int)), this, SLOT(slotComparatorChanged(int)));
}

void SearchCriterionSelector::slotComparatorChanged(int index)
{
    Q_ASSERT(index >= 0);

    // only show the value widget if an operation is defined by the comparator
    const int descIndex = m_descriptionsBox->currentIndex();
    const SearchCriterionDescription& descr = m_descriptions[descIndex];
    const SearchCriterionDescription::Comparator& comp = descr.comparators()[index];

    m_valueWidget->initializeValue(comp.autoValueType);
    // only show the value widget, if an operation is defined
    // and no automatic calculation is provided
    m_valueWidget->setVisible(comp.isActive && comp.autoValueType.isEmpty());

    emit criterionChanged();
}

void SearchCriterionSelector::createDescriptions()
{
    Q_ASSERT(m_descriptionsBox != 0);
    Q_ASSERT(m_comparatorBox != 0);

    // TODO: maybe this creation should be forwarded to a factory if
    // the number of items increases in future
    QList<SearchCriterionDescription::Comparator> defaultComps;
    defaultComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Greater Than"), Nepomuk::Query::ComparisonTerm::Greater));
    defaultComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Greater Than or Equal to"), Nepomuk::Query::ComparisonTerm::GreaterOrEqual));
    defaultComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Less Than"), Nepomuk::Query::ComparisonTerm::Smaller));
    defaultComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Less Than or Equal to"), Nepomuk::Query::ComparisonTerm::SmallerOrEqual));

    // add "Date" description
    QList<SearchCriterionDescription::Comparator> dateComps;
    dateComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Anytime")));
    dateComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Today"), Nepomuk::Query::ComparisonTerm::GreaterOrEqual, "today"));
    dateComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "This Week"), Nepomuk::Query::ComparisonTerm::GreaterOrEqual, "thisWeek"));
    dateComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "This Month"), Nepomuk::Query::ComparisonTerm::GreaterOrEqual, "thisMonth"));
    dateComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "This Year"), Nepomuk::Query::ComparisonTerm::GreaterOrEqual, "thisYear"));
    foreach (const SearchCriterionDescription::Comparator& comp, defaultComps) {
        dateComps.append(comp);
    }

    DateValue* dateValue = new DateValue(this);
    dateValue->hide();
    SearchCriterionDescription date(i18nc("@label", "Date:"),
                                    Nepomuk::Vocabulary::NIE::lastModified(),
                                    dateComps,
                                    dateValue);
    Q_ASSERT(static_cast<int>(SearchCriterionSelector::Date) == 0);
    m_descriptions.append(date);

    // add "Size" description
    QList<SearchCriterionDescription::Comparator> sizeComps = defaultComps;
    sizeComps.insert(0, SearchCriterionDescription::Comparator(i18nc("@label Any (file size)", "Any")));

    SizeValue* sizeValue = new SizeValue(this);
    sizeValue->hide();
    SearchCriterionDescription size(i18nc("@label", "Size:"),
                                    Soprano::Vocabulary::NAO::lastModified(), // TODO
                                    sizeComps,
                                    sizeValue);
    Q_ASSERT(static_cast<int>(SearchCriterionSelector::Size) == 1);
    m_descriptions.append(size);

    // add "Tag" description
    QList<SearchCriterionDescription::Comparator> tagComps;
    tagComps.append(SearchCriterionDescription::Comparator(i18nc("@label All (tags)", "All")));
    tagComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Equal to"), Nepomuk::Query::ComparisonTerm::Equal));
    // It is unclear yet how to express != for tags with the new Nepomuk query API. Disable it for KDE 4.4,
    // but leave the translation string there to be able to enable this functionality for KDE 4.4.x:
    const QString dummy = i18nc("@label", "Not Equal to");
    Q_UNUSED(dummy);
    //tagComps.append(SearchCriterionDescription::Comparator(i18nc("@label", "Not Equal to"), Nepomuk::Query::ComparisonTerm::Equal)); // TODO

    TagValue* tagValue = new TagValue(this);
    tagValue->hide();
    SearchCriterionDescription tag(i18nc("@label", "Tag:"),
                                   Soprano::Vocabulary::NAO::hasTag(),
                                   tagComps,
                                   tagValue);
    Q_ASSERT(static_cast<int>(SearchCriterionSelector::Tag) == 2);
    m_descriptions.append(tag);

    // add "Rating" description
    QList<SearchCriterionDescription::Comparator> ratingComps = defaultComps;
    ratingComps.insert(0, SearchCriterionDescription::Comparator(i18nc("@label Any (rating)", "Any")));

    RatingValue* ratingValue = new RatingValue(this);
    ratingValue->hide();
    SearchCriterionDescription rating(i18nc("@label", "Rating:"),
                                      Soprano::Vocabulary::NAO::numericRating(),
                                      ratingComps,
                                      ratingValue);
    Q_ASSERT(static_cast<int>(SearchCriterionSelector::Rating) == 3);
    m_descriptions.append(rating);

    // add all descriptions to the combo box and connect the value widgets
    int i = 0;
    foreach (const SearchCriterionDescription& desc, m_descriptions) {
        m_descriptionsBox->addItem(desc.name(), i);
        connect(desc.valueWidget(), SIGNAL(valueChanged(Nepomuk::Query::LiteralTerm)), this, SIGNAL(criterionChanged()));
        ++i;
    }
}

#include "searchcriterionselector.moc"