/***************************************************************************
*    Copyright (C) 2010 by Peter Penz <peter.penz19@gmail.com>            *
*                                                                         *
*    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 "dolphinsearchbox.h"

#include "dolphin_searchsettings.h"
#include "dolphinfacetswidget.h"

#include <QIcon>
#include <KLineEdit>
#include <KLocale>
#include <KSeparator>
#include <KGlobalSettings>

#include <QButtonGroup>
#include <QDir>
#include <QEvent>
#include <QFormLayout>
#include <QHBoxLayout>
#include <QKeyEvent>
#include <QLabel>
#include <QScrollArea>
#include <QTimer>
#include <QToolButton>
#include <QVBoxLayout>

#ifdef HAVE_BALOO
    #include <Baloo/NaturalFileQueryParser>
    #include <Baloo/QueryBuilder>
    #include <Baloo/Query>
    #include <Baloo/Term>
    #include <Baloo/IndexerConfig>
#endif

DolphinSearchBox::DolphinSearchBox(QWidget* parent) :
    QWidget(parent),
    m_startedSearching(false),
    m_active(true),
    m_topLayout(0),
    m_searchLabel(0),
    m_searchInput(0),
    m_optionsScrollArea(0),
    m_fileNameButton(0),
    m_contentButton(0),
    m_separator(0),
    m_fromHereButton(0),
    m_everywhereButton(0),
    m_facetsToggleButton(0),
    m_facetsWidget(0),
    m_searchPath(),
    m_startSearchTimer(0)
{
}

DolphinSearchBox::~DolphinSearchBox()
{
    saveSettings();
}

void DolphinSearchBox::setText(const QString& text)
{
    m_searchInput->setText(text);
}

QString DolphinSearchBox::text() const
{
    return m_searchInput->text();
}

void DolphinSearchBox::setSearchPath(const KUrl& url)
{
    m_searchPath = url;

    QFontMetrics metrics(m_fromHereButton->font());
    const int maxWidth = metrics.height() * 8;

    QString location = url.fileName();
    if (location.isEmpty()) {
        if (url.isLocalFile()) {
            location = QLatin1String("/");
        } else {
            location = url.protocol() + QLatin1String(" - ") + url.host();
        }
    }

    const QString elidedLocation = metrics.elidedText(location, Qt::ElideMiddle, maxWidth);
    m_fromHereButton->setText(i18nc("action:button", "From Here (%1)", elidedLocation));

    const bool showSearchFromButtons = url.isLocalFile();
    m_separator->setVisible(showSearchFromButtons);
    m_fromHereButton->setVisible(showSearchFromButtons);
    m_everywhereButton->setVisible(showSearchFromButtons);

    bool hasFacetsSupport = false;
#ifdef HAVE_BALOO
    const Baloo::IndexerConfig searchInfo;
    hasFacetsSupport = searchInfo.fileIndexingEnabled() && searchInfo.shouldBeIndexed(m_searchPath.toLocalFile());
#endif
    m_facetsWidget->setEnabled(hasFacetsSupport);
}

KUrl DolphinSearchBox::searchPath() const
{
    return m_searchPath;
}

KUrl DolphinSearchBox::urlForSearching() const
{
    KUrl url;
    bool useBalooSearch = false;
#ifdef HAVE_BALOO
    const Baloo::IndexerConfig searchInfo;
    useBalooSearch = searchInfo.fileIndexingEnabled() && searchInfo.shouldBeIndexed(m_searchPath.toLocalFile());
#endif
    if (useBalooSearch) {
        url = balooUrlForSearching();
    } else {
        url.setProtocol("filenamesearch");
        url.addQueryItem("search", m_searchInput->text());
        if (m_contentButton->isChecked()) {
            url.addQueryItem("checkContent", "yes");
        }

        QString encodedUrl;
        if (m_everywhereButton->isChecked()) {
            // It is very unlikely, that the majority of Dolphins target users
            // mean "the whole harddisk" instead of "my home folder" when
            // selecting the "Everywhere" button.
            encodedUrl = QDir::homePath();
        } else {
            encodedUrl = m_searchPath.url();
        }
        url.addQueryItem("url", encodedUrl);
    }

    return url;
}

void DolphinSearchBox::fromSearchUrl(const KUrl& url)
{
    if (url.protocol() == "baloosearch") {
        fromBalooSearchUrl(url);
    } else if (url.protocol() == "filenamesearch") {
        const QMap<QString, QString>& queryItems = url.queryItems();
        setText(queryItems.value("search"));
        setSearchPath(queryItems.value("url"));
        m_contentButton->setChecked(queryItems.value("checkContent") == "yes");
    } else {
        setText(QString());
        setSearchPath(url);
    }
}

void DolphinSearchBox::selectAll()
{
    m_searchInput->selectAll();
}

void DolphinSearchBox::setActive(bool active)
{
    if (active != m_active) {
        m_active = active;

        if (active) {
            emit activated();
        }
    }
}

bool DolphinSearchBox::isActive() const
{
    return m_active;
}

bool DolphinSearchBox::event(QEvent* event)
{
    if (event->type() == QEvent::Polish) {
        init();
    }
    return QWidget::event(event);
}

void DolphinSearchBox::showEvent(QShowEvent* event)
{
    if (!event->spontaneous()) {
        m_searchInput->setFocus();
        m_startedSearching = false;
    }
}

void DolphinSearchBox::keyReleaseEvent(QKeyEvent* event)
{
    QWidget::keyReleaseEvent(event);
    if (event->key() == Qt::Key_Escape) {
        if (m_searchInput->text().isEmpty()) {
            emit closeRequest();
        } else {
            m_searchInput->clear();
        }
    }
}

bool DolphinSearchBox::eventFilter(QObject* obj, QEvent* event)
{
    switch (event->type()) {
    case QEvent::FocusIn:
        setActive(true);
        setFocus();
        break;

    default:
        break;
    }

    return QObject::eventFilter(obj, event);
}

void DolphinSearchBox::emitSearchRequest()
{
    m_startSearchTimer->stop();
    m_startedSearching = true;
    emit searchRequest();
}

void DolphinSearchBox::emitCloseRequest()
{
    m_startSearchTimer->stop();
    m_startedSearching = false;
    emit closeRequest();
}

void DolphinSearchBox::slotConfigurationChanged()
{
    saveSettings();
    if (m_startedSearching) {
        emitSearchRequest();
    }
}

void DolphinSearchBox::slotSearchTextChanged()
{
    const QString text = m_searchInput->text();

    if (text.isEmpty()) {
        m_startSearchTimer->stop();
    } else {
        m_startSearchTimer->start();
    }
    emit searchTextChanged(text);
}

void DolphinSearchBox::slotReturnPressed()
{
    emitSearchRequest();
    emit returnPressed(m_searchInput->text());
}

void DolphinSearchBox::updateSearchInputParsing()
{
#ifdef HAVE_BALOO
    m_searchInput->setParsingEnabled(m_contentButton->isChecked());
#endif
}

void DolphinSearchBox::slotFacetsButtonToggled()
{
    const bool facetsIsVisible = !m_facetsWidget->isVisible();
    m_facetsWidget->setVisible(facetsIsVisible);
    updateFacetsToggleButton();
}

void DolphinSearchBox::slotFacetChanged()
{
    m_startedSearching = true;
    m_startSearchTimer->stop();
    emit searchRequest();
}

void DolphinSearchBox::initButton(QToolButton* button)
{
    button->installEventFilter(this);
    button->setAutoExclusive(true);
    button->setAutoRaise(true);
    button->setCheckable(true);
    connect(button, &QToolButton::clicked, this, &DolphinSearchBox::slotConfigurationChanged);
}

void DolphinSearchBox::loadSettings()
{
    if (SearchSettings::location() == QLatin1String("Everywhere")) {
        m_everywhereButton->setChecked(true);
    } else {
        m_fromHereButton->setChecked(true);
    }

    if (SearchSettings::what() == QLatin1String("Content")) {
        m_contentButton->setChecked(true);
    } else {
        m_fileNameButton->setChecked(true);
    }

    m_facetsWidget->setVisible(SearchSettings::showFacetsWidget());
    updateSearchInputParsing();
}

void DolphinSearchBox::saveSettings()
{
    SearchSettings::setLocation(m_fromHereButton->isChecked() ? "FromHere" : "Everywhere");
    SearchSettings::setWhat(m_fileNameButton->isChecked() ? "FileName" : "Content");
    SearchSettings::setShowFacetsWidget(m_facetsToggleButton->isChecked());
    SearchSettings::self()->writeConfig();
}

void DolphinSearchBox::init()
{
    // Create close button
    QToolButton* closeButton = new QToolButton(this);
    closeButton->setAutoRaise(true);
    closeButton->setIcon(QIcon::fromTheme("dialog-close"));
    closeButton->setToolTip(i18nc("@info:tooltip", "Quit searching"));
    connect(closeButton, &QToolButton::clicked, this, &DolphinSearchBox::emitCloseRequest);

    // Create search label
    m_searchLabel = new QLabel(this);

    // Create search box
#ifdef HAVE_BALOO
    m_queryParser.reset(new Baloo::NaturalFileQueryParser);
    m_searchInput = new Baloo::QueryBuilder(m_queryParser.data(), this);
    connect(m_searchInput, &Baloo::QueryBuilder::editingFinished,
            this, &DolphinSearchBox::slotReturnPressed);
    connect(m_searchInput, &Baloo::QueryBuilder::textChanged,
            this, &DolphinSearchBox::slotSearchTextChanged);
#else
    m_searchInput = new KLineEdit(this);
    m_searchInput->installEventFilter(this);
    m_searchInput->setClearButtonShown(true);
    m_searchInput->setFont(KGlobalSettings::generalFont());
    connect(m_searchInput, &KLineEdit::returnPressed,
            this, &DolphinSearchBox::slotReturnPressed);
    connect(m_searchInput, &KLineEdit::textChanged,
            this, &DolphinSearchBox::slotSearchTextChanged);
#endif
    setFocusProxy(m_searchInput);

    // Apply layout for the search input
    QHBoxLayout* searchInputLayout = new QHBoxLayout();
    searchInputLayout->setMargin(0);
    searchInputLayout->addWidget(closeButton);
    searchInputLayout->addWidget(m_searchLabel);
    searchInputLayout->addWidget(m_searchInput);

    // Create "Filename" and "Content" button
    m_fileNameButton = new QToolButton(this);
    m_fileNameButton->setText(i18nc("action:button", "Filename"));
    initButton(m_fileNameButton);

    m_contentButton = new QToolButton();
    m_contentButton->setText(i18nc("action:button", "Content"));
    initButton(m_contentButton);

    QButtonGroup* searchWhatGroup = new QButtonGroup(this);
    searchWhatGroup->addButton(m_fileNameButton);
    searchWhatGroup->addButton(m_contentButton);
    connect(searchWhatGroup, static_cast<void (QButtonGroup::*)(int)>(&QButtonGroup::buttonClicked),
            this, &DolphinSearchBox::updateSearchInputParsing);

    m_separator = new KSeparator(Qt::Vertical, this);

    // Create "From Here" and "Everywhere"button
    m_fromHereButton = new QToolButton(this);
    m_fromHereButton->setText(i18nc("action:button", "From Here"));
    initButton(m_fromHereButton);

    m_everywhereButton = new QToolButton(this);
    m_everywhereButton->setText(i18nc("action:button", "Everywhere"));
    initButton(m_everywhereButton);

    QButtonGroup* searchLocationGroup = new QButtonGroup(this);
    searchLocationGroup->addButton(m_fromHereButton);
    searchLocationGroup->addButton(m_everywhereButton);

    // Create "Facets" widgets
    m_facetsToggleButton = new QToolButton(this);
    m_facetsToggleButton->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
    initButton(m_facetsToggleButton);
    connect(m_facetsToggleButton, &QToolButton::clicked, this, &DolphinSearchBox::slotFacetsButtonToggled);

    m_facetsWidget = new DolphinFacetsWidget(this);
    m_facetsWidget->installEventFilter(this);
    m_facetsWidget->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Maximum);
    connect(m_facetsWidget, &DolphinFacetsWidget::facetChanged, this, &DolphinSearchBox::slotFacetChanged);

    // Apply layout for the options
    QHBoxLayout* optionsLayout = new QHBoxLayout();
    optionsLayout->setMargin(0);
    optionsLayout->addWidget(m_fileNameButton);
    optionsLayout->addWidget(m_contentButton);
    optionsLayout->addWidget(m_separator);
    optionsLayout->addWidget(m_fromHereButton);
    optionsLayout->addWidget(m_everywhereButton);
    optionsLayout->addStretch(1);
    optionsLayout->addWidget(m_facetsToggleButton);

    // Put the options into a QScrollArea. This prevents increasing the view width
    // in case that not enough width for the options is available.
    QWidget* optionsContainer = new QWidget(this);
    optionsContainer->setLayout(optionsLayout);

    m_optionsScrollArea = new QScrollArea(this);
    m_optionsScrollArea->setFrameShape(QFrame::NoFrame);
    m_optionsScrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    m_optionsScrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    m_optionsScrollArea->setMaximumHeight(optionsContainer->sizeHint().height());
    m_optionsScrollArea->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
    m_optionsScrollArea->setWidget(optionsContainer);
    m_optionsScrollArea->setWidgetResizable(true);

    m_topLayout = new QVBoxLayout(this);
    m_topLayout->setMargin(0);
    m_topLayout->addLayout(searchInputLayout);
    m_topLayout->addWidget(m_optionsScrollArea);
    m_topLayout->addWidget(m_facetsWidget);

    loadSettings();

    // The searching should be started automatically after the user did not change
    // the text within one second
    m_startSearchTimer = new QTimer(this);
    m_startSearchTimer->setSingleShot(true);
    m_startSearchTimer->setInterval(1000);
    connect(m_startSearchTimer, &QTimer::timeout, this, &DolphinSearchBox::emitSearchRequest);

    updateFacetsToggleButton();
}

KUrl DolphinSearchBox::balooUrlForSearching() const
{
#ifdef HAVE_BALOO
    const QString text = m_searchInput->text();

    Baloo::Query query;

    if (m_contentButton->isChecked()) {
        query = m_queryParser->parse(text, Baloo::NaturalQueryParser::DetectFilenamePattern);
    } else {
        query.setTerm(Baloo::Term(QLatin1String("filename"), text));
    }

    // Configure the query so that it returns files and takes the rating into account
    query.addType("File");
    query.addType(m_facetsWidget->facetType());

    Baloo::Term term(Baloo::Term::And);
    Baloo::Term ratingTerm = m_facetsWidget->ratingTerm();

    if (ratingTerm.isValid()) {
        term.addSubTerm(query.term());
        term.addSubTerm(ratingTerm);

        query.setTerm(term);
    }

    if (m_fromHereButton->isChecked()) {
        query.addCustomOption("includeFolder", m_searchPath.toLocalFile());
    }

    return query.toSearchUrl(i18nc("@title UDS_DISPLAY_NAME for a KIO directory listing. %1 is the query the user entered.",
                                   "Query Results from '%1'", text));
#else
    return KUrl();
#endif
}

void DolphinSearchBox::fromBalooSearchUrl(const KUrl& url)
{
#ifdef HAVE_BALOO
    const Baloo::Query query = Baloo::Query::fromSearchUrl(url);
    const Baloo::Term term = query.term();

    // Block all signals to avoid unnecessary "searchRequest" signals
    // while we adjust the search text and the facet widget.
    blockSignals(true);

    const QVariantMap customOptions = query.customOptions();
    if (customOptions.contains("includeFolder")) {
        setSearchPath(customOptions.value("includeFolder").toString());
    } else {
        setSearchPath(QDir::homePath());
    }

    if (!query.searchString().isEmpty()) {
        setText(query.searchString());
    }

    QStringList types = query.types();
    types.removeOne("File"); // We are only interested in facet widget types
    if (!types.isEmpty()) {
        m_facetsWidget->setFacetType(types.first());
    }

    foreach (const Baloo::Term& subTerm, term.subTerms()) {
        const QString property = subTerm.property();

        if (property == QLatin1String("filename")) {
            setText(subTerm.value().toString());
        } else if (m_facetsWidget->isRatingTerm(subTerm)) {
            m_facetsWidget->setRatingTerm(subTerm);
        }
    }

    m_startSearchTimer->stop();
    blockSignals(false);
#endif
}

void DolphinSearchBox::updateFacetsToggleButton()
{
    const bool facetsIsVisible = SearchSettings::showFacetsWidget();
    m_facetsToggleButton->setChecked(facetsIsVisible ? true : false);
    m_facetsToggleButton->setIcon(QIcon::fromTheme(facetsIsVisible ? "arrow-up-double" : "arrow-down-double"));
    m_facetsToggleButton->setText(facetsIsVisible ? i18nc("action:button", "Fewer Options") : i18nc("action:button", "More Options"));
}