/***************************************************************************
 *   Copyright (C) 2006 by Peter Penz (<peter.penz@gmx.at>)                *
 *   Copyright (C) 2006 by Aaron J. Seigo (<aseigo@kde.org>)               *
 *   Copyright (C) 2006 by Patrice Tremblay                                *
 *   Copyright (C) 2007 by Kevin Ottens (ervin@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, Boston, MA  02110-1301  USA          *
 ***************************************************************************/

#include "kurlnavigator.h"

#include "kfileplacesselector_p.h"
#include "kprotocolcombo_p.h"
#include "kurlnavigatorbutton_p.h"

#include <assert.h>

#include <kfileitem.h>
#include <kicon.h>
#include <klocale.h>
#include <kprotocolinfo.h>
#include <kurlcombobox.h>
#include <kurlcompletion.h>

#include <QApplication>
#include <QClipboard>
#include <QDir>
#include <QHBoxLayout>
#include <QLabel>
#include <QLineEdit>
#include <QLinkedList>
#include <QMouseEvent>
#include <QToolButton>

/**
 * @brief Represents the history element of an URL.
 *
 * A history element contains the URL, the name of the current file
 * (the 'current file' is the file where the cursor is located) and
 * the x- and y-position of the content.
 */
class HistoryElem {
public:
    HistoryElem();
    HistoryElem(const KUrl& url);
    ~HistoryElem(); // non virtual

    const KUrl& url() const { return m_url; }

    void setCurrentFileName(const QString& name) { m_currentFileName = name; }
    const QString& currentFileName() const { return m_currentFileName; }

    void setContentsX(int x) { m_contentsX = x; }
    int contentsX() const { return m_contentsX; }

    void setContentsY(int y) { m_contentsY = y; }
    int contentsY() const { return m_contentsY; }

private:
    KUrl m_url;
    QString m_currentFileName;
    int m_contentsX;
    int m_contentsY;
};

HistoryElem::HistoryElem() :
    m_url(),
    m_currentFileName(),
    m_contentsX(0),
    m_contentsY(0)
{
}

HistoryElem::HistoryElem(const KUrl& url) :
    m_url(url),
    m_currentFileName(),
    m_contentsX(0),
    m_contentsY(0)
{
}

HistoryElem::~HistoryElem()
{
}

class KUrlNavigator::Private
{
public:
    Private(KUrlNavigator* q, KFilePlacesModel* placesModel);

    void slotReturnPressed(const QString&);
    void slotRemoteHostActivated();
    void slotProtocolChanged(const QString&);

    /**
     * Appends the widget at the end of the URL navigator. It is assured
     * that the filler widget remains as last widget to fill the remaining
     * width.
     */
    void appendWidget(QWidget* widget);

    /**
     * Switches the navigation bar between the breadcrumb view and the
     * traditional view (see setUrlEditable()) and is connected to the clicked signal
     * of the navigation bar button.
     */
    void switchView();

    /**
     * Updates the history element with the current file item
     * and the contents position.
     */
    void updateHistoryElem();
    void updateContent();

    /**
     * Updates all buttons to have one button for each part of the
     * path \a path. Existing buttons, which are available by m_navButtons,
     * are reused if possible. If the path is longer, new buttons will be
     * created, if the path is shorter, the remaining buttons will be deleted.
     * @param startIndex    Start index of path part (/), where the buttons
     *                      should be created for each following part.
     */
    void updateButtons(const QString& path, int startIndex);

    /**
     * Deletes all URL navigator buttons. m_navButtons is
     * empty after this operation.
     */
    void deleteButtons();


    bool m_active;
    bool m_showHiddenFiles;
    int m_historyIndex;

    QHBoxLayout* m_layout;

    QList<HistoryElem> m_history;
    QToolButton* m_toggleButton;
    KFilePlacesSelector* m_placesSelector;
    KUrlComboBox* m_pathBox;
    KProtocolCombo* m_protocols;
    QLabel* m_protocolSeparator;
    QLineEdit* m_host;
    QLinkedList<KUrlNavigatorButton*> m_navButtons;
    QWidget* m_filler;
    QString m_homeUrl;
    KUrlNavigator* q;
};


KUrlNavigator::Private::Private(KUrlNavigator* q, KFilePlacesModel* placesModel)
    :
    m_active(true),
    m_showHiddenFiles(false),
    m_historyIndex(0),
    m_layout(new QHBoxLayout),
    m_protocols(0),
    m_protocolSeparator(0),
    m_host(0),
    m_filler(0),
    q(q)
{
    m_layout->setSpacing(0);
    m_layout->setMargin(0);

    // initialize toggle button which switches between the breadcrumb view
    // and the traditional view
    m_toggleButton = new QToolButton();
    m_toggleButton->setCheckable(true);
    m_toggleButton->setAutoRaise(true);
    m_toggleButton->setIcon(KIcon("editinput")); // TODO: is just a placeholder icon (?)
    m_toggleButton->setFocusPolicy(Qt::NoFocus);
    m_toggleButton->setMinimumHeight(q->minimumHeight());
    connect(m_toggleButton, SIGNAL(clicked()),
            q, SLOT(switchView()));

    // initialize the places selector
    m_placesSelector = new KFilePlacesSelector(q, placesModel);
    connect(m_placesSelector, SIGNAL(placeActivated(const KUrl&)),
            q, SLOT(setUrl(const KUrl&)));

    // initialize the path box of the traditional view
    m_pathBox = new KUrlComboBox(KUrlComboBox::Directories, true, q);

    KUrlCompletion* kurlCompletion = new KUrlCompletion(KUrlCompletion::DirCompletion);
    m_pathBox->setCompletionObject(kurlCompletion);
    m_pathBox->setAutoDeleteCompletionObject(true);

    connect(m_pathBox, SIGNAL(returnPressed(QString)),
            q, SLOT(slotReturnPressed(QString)));
    connect(m_pathBox, SIGNAL(urlActivated(KUrl)),
            q, SLOT(setUrl(KUrl)));

    // Append a filler widget at the end, which automatically resizes to the
    // maximum available width. This assures that the URL navigator uses the
    // whole width, so that the clipboard content can be dropped.
    m_filler = new QWidget();
    m_filler->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);

    m_layout->addWidget(m_toggleButton);
    m_layout->addWidget(m_placesSelector);
    m_layout->addWidget(m_pathBox);
    m_layout->addWidget(m_filler);
}

void KUrlNavigator::Private::appendWidget(QWidget* widget)
{
    m_layout->insertWidget(m_layout->count() - 1, widget);
}

void KUrlNavigator::Private::slotReturnPressed(const QString& text)
{
    // Parts of the following code have been taken
    // from the class KateFileSelector located in
    // kate/app/katefileselector.hpp of Kate.
    // Copyright (C) 2001 Christoph Cullmann <cullmann@kde.org>
    // Copyright (C) 2001 Joseph Wenninger <jowenn@kde.org>
    // Copyright (C) 2001 Anders Lund <anders.lund@lund.tdcadsl.dk>

    KUrl typedUrl(text);
    if (typedUrl.hasPass()) {
        typedUrl.setPass(QString());
    }

    QStringList urls = m_pathBox->urls();
    urls.removeAll(typedUrl.url());
    urls.prepend(typedUrl.url());
    m_pathBox->setUrls(urls, KUrlComboBox::RemoveBottom);

    q->setUrl(typedUrl);
    // The URL might have been adjusted by KUrlNavigator::setUrl(), hence
    // synchronize the result in the path box.
    m_pathBox->setUrl(q->url());
}

void KUrlNavigator::Private::slotRemoteHostActivated()
{
    KUrl u = q->url();

    QString host = m_host->text();
    QString user;

    int marker = host.indexOf("@");
    if (marker != -1)
    {
        user = host.left(marker);
        u.setUser(user);
        host = host.right(host.length() - marker - 1);
    }

    marker = host.indexOf("/");
    if (marker != -1)
    {
        u.setPath(host.right(host.length() - marker));
        host.truncate(marker);
    }
    else
    {
        u.setPath("");
    }

    if (m_protocols->currentProtocol() != u.protocol() ||
        host != u.host() ||
        user != u.user())
    {
        u.setProtocol(m_protocols->currentProtocol());
        u.setHost(m_host->text());

        //TODO: get rid of this HACK for file:///!
        if (u.protocol() == "file")
        {
            u.setHost("");
            if (u.path().isEmpty())
            {
                u.setPath("/");
            }
        }

        q->setUrl(u);
    }
}

void KUrlNavigator::Private::slotProtocolChanged(const QString& protocol)
{
    KUrl url;
    url.setProtocol(protocol);
    //url.setPath(KProtocolInfo::protocolClass(protocol) == ":local" ? "/" : "");
    url.setPath("/");
    QLinkedList<KUrlNavigatorButton*>::const_iterator it = m_navButtons.begin();
    const QLinkedList<KUrlNavigatorButton*>::const_iterator itEnd = m_navButtons.end();
    while (it != itEnd) {
        (*it)->close();
        (*it)->deleteLater();
        ++it;
    }
    m_navButtons.clear();

    if (KProtocolInfo::protocolClass(protocol) == ":local") {
        q->setUrl(url);
    }
    else {
        if (!m_host) {
            m_protocolSeparator = new QLabel("://", q);
            appendWidget(m_protocolSeparator);
            m_host = new QLineEdit(q);
            appendWidget(m_host);

            connect(m_host, SIGNAL(lostFocus()),
                    q, SLOT(slotRemoteHostActivated()));
            connect(m_host, SIGNAL(returnPressed()),
                    q, SLOT(slotRemoteHostActivated()));
        }
        else {
            m_host->setText("");
        }
        m_protocolSeparator->show();
        m_host->show();
        m_host->setFocus();
    }
}

#if 0
void KUrlNavigator::slotRedirection(const KUrl& oldUrl, const KUrl& newUrl)
{
// kDebug() << "received redirection to " << newUrl << endl;
kDebug() << "received redirection from " << oldUrl << " to " << newUrl << endl;
/*    UrlStack::iterator it = m_urls.find(oldUrl);
    if (it != m_urls.end())
    {
        m_urls.erase(++it, m_urls.end());
    }

    m_urls.append(newUrl);*/
}
#endif

void KUrlNavigator::Private::switchView()
{
    updateContent();
    if (q->isUrlEditable()) {
        m_pathBox->setFocus();
    } else {
        q->setUrl(m_pathBox->currentText());
    }
    emit q->requestActivation();
}

void KUrlNavigator::Private::updateHistoryElem()
{
    assert(m_historyIndex >= 0);
    const KFileItem* item = 0; // TODO: m_dolphinView->currentFileItem();
    if (item != 0) {
        HistoryElem& hist = m_history[m_historyIndex];
        hist.setCurrentFileName(item->name());
    }
}

void KUrlNavigator::Private::updateContent()
{
    m_placesSelector->updateSelection(q->url());

    m_toggleButton->setToolTip(QString());
    QString path(q->url().pathOrUrl());

    // TODO: prevent accessing the DolphinMainWindow out from this scope
    //const QAction* action = dolphinView()->mainWindow()->actionCollection()->action("editable_location");
    // TODO: registry of default shortcuts
    //QString shortcut = action? action->shortcut().toString() : "Ctrl+L";
    const QString shortcut = "Ctrl+L";

    if (m_toggleButton->isChecked()) {
        delete m_protocols; m_protocols = 0;
        delete m_protocolSeparator; m_protocolSeparator = 0;
        delete m_host; m_host = 0;
        deleteButtons();
        m_filler->hide();

        m_toggleButton->setToolTip(i18n("Browse (%1, Escape)", shortcut));

        q->setSizePolicy(QSizePolicy::Minimum, QSizePolicy::Fixed);
        m_pathBox->show();
        m_pathBox->setUrl(q->url());
    }
    else {
        m_toggleButton->setToolTip(i18n("Edit location (%1)", shortcut));

        q->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
        m_pathBox->hide();
        m_filler->show();

        // get the data from the currently selected place
        KUrl placeUrl = m_placesSelector->selectedPlaceUrl();

        QString placePath;
        if (!placeUrl.isValid()) {
            // No place is a part of the current Url.
            // The following code tries to guess the place
            // path. E. g. "fish://root@192.168.0.2/var/lib" writes
            // "fish://root@192.168.0.2" to 'placePath', which leads to the
            // navigation indication 'Custom Path > var > lib".
            int idx = path.indexOf(QString("//"));
            idx = path.indexOf("/", (idx < 0) ? 0 : idx + 2);
            placePath = (idx < 0) ? path : path.left(idx);
        }
        else {
            placePath = placeUrl.pathOrUrl();
        }
        const uint len = placePath.length();

        // calculate the start point for the URL navigator buttons by counting
        // the slashs inside the place URL
        int slashCount = 0;
        for (uint i = 0; i < len; ++i) {
            if (placePath.at(i) == QChar('/')) {
                ++slashCount;
            }
        }
        if ((len > 0) && placePath.at(len - 1) == QChar('/')) {
            assert(slashCount > 0);
            --slashCount;
        }

        const KUrl currentUrl = q->url();
        if (!currentUrl.isLocalFile() && !placeUrl.isValid()) {
            QString protocol = currentUrl.protocol();
            if (!m_protocols) {
                deleteButtons();
                m_protocols = new KProtocolCombo(protocol, q);
                appendWidget(m_protocols);
                connect(m_protocols, SIGNAL(activated(QString)),
                        q, SLOT(slotProtocolChanged(QString)));
            }
            else {
                m_protocols->setProtocol(protocol);
            }
            m_protocols->show();

            if (KProtocolInfo::protocolClass(protocol) != ":local") {
                QString hostText = currentUrl.host();

                if (!currentUrl.user().isEmpty()) {
                    hostText = currentUrl.user() + '@' + hostText;
                }

                if (!m_host) {
                    // ######### TODO: this code is duplicated from slotProtocolChanged!
                    m_protocolSeparator = new QLabel("://", q);
                    appendWidget(m_protocolSeparator);
                    m_host = new QLineEdit(hostText, q);
                    appendWidget(m_host);

                    connect(m_host, SIGNAL(lostFocus()),
                            q, SLOT(slotRemoteHostActivated()));
                    connect(m_host, SIGNAL(returnPressed()),
                            q, SLOT(slotRemoteHostActivated()));
                }
                else {
                    m_host->setText(hostText);
                }
                m_protocolSeparator->show();
                m_host->show();
            }
            else {
                delete m_protocolSeparator; m_protocolSeparator = 0;
                delete m_host; m_host = 0;
            }
        }
        else if (m_protocols) {
            m_protocols->hide();

            if (m_host) {
                m_protocolSeparator->hide();
                m_host->hide();
            }
        }

        updateButtons(path, slashCount);
    }
}

void KUrlNavigator::Private::updateButtons(const QString& path, int startIndex)
{
    QLinkedList<KUrlNavigatorButton*>::iterator it = m_navButtons.begin();
    const QLinkedList<KUrlNavigatorButton*>::const_iterator itEnd = m_navButtons.end();
    bool createButton = false;
    const KUrl currentUrl = q->url();

    int idx = startIndex;
    bool hasNext = true;
    do {
        createButton = (it == itEnd);

        const QString dirName = path.section('/', idx, idx);
        const bool isFirstButton = (idx == startIndex);
        hasNext = isFirstButton || !dirName.isEmpty();
        if (hasNext) {
            QString text;
            if (isFirstButton) {
                // the first URL navigator button should get the name of the
                // place instead of the directory name
                const KUrl placeUrl = m_placesSelector->selectedPlaceUrl();
                text = m_placesSelector->selectedPlaceText();
                if (text.isEmpty()) {
                    if (currentUrl.isLocalFile()) {
                        text = i18n("Custom Path");
                    }
                    else {
                        ++idx;
                        continue;
                    }
                }
            }

            KUrlNavigatorButton* button = 0;
            if (createButton) {
                button = new KUrlNavigatorButton(idx, q);
                appendWidget(button);
            }
            else {
                button = *it;
                button->setIndex(idx);
            }

            if (isFirstButton) {
                button->setText(text);
            }

            if (createButton) {
                button->show();
                m_navButtons.append(button);
            }
            else {
                ++it;
            }
            ++idx;
        }
    } while (hasNext);

    // delete buttons which are not used anymore
    QLinkedList<KUrlNavigatorButton*>::iterator itBegin = it;
    while (it != itEnd) {
        (*it)->close();
        (*it)->deleteLater();
        ++it;
    }
    m_navButtons.erase(itBegin, m_navButtons.end());
}

void KUrlNavigator::Private::deleteButtons()
{
    QLinkedList<KUrlNavigatorButton*>::iterator itBegin = m_navButtons.begin();
    QLinkedList<KUrlNavigatorButton*>::iterator itEnd = m_navButtons.end();
    QLinkedList<KUrlNavigatorButton*>::iterator it = itBegin;
    while (it != itEnd) {
        (*it)->close();
        (*it)->deleteLater();
        ++it;
    }
    m_navButtons.erase(itBegin, itEnd);
}

////


KUrlNavigator::KUrlNavigator(KFilePlacesModel* placesModel,
                           const KUrl& url,
                           QWidget* parent) :
    QWidget(parent),
    d( new Private(this, placesModel) )
{
    d->m_history.prepend(HistoryElem(url));

    QFontMetrics fontMetrics(font());
    setMinimumHeight(fontMetrics.height() + 10);

    setLayout(d->m_layout);

    d->updateContent();
}

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

const KUrl& KUrlNavigator::url() const
{
    assert(!d->m_history.empty());
    return d->m_history[d->m_historyIndex].url();
}

KUrl KUrlNavigator::url(int index) const
{
    assert(index >= 0);
    // keep scheme, hostname etc. maybe we will need this in the future
    // for e.g. browsing ftp repositories.
    KUrl newurl(url());
    newurl.setPath(QString());
    QString path(url().path());

    if (!path.isEmpty()) {
        if (index == 0) //prevent the last "/" from being stripped
            path = "/"; //or we end up with an empty path
        else
            path = path.section('/', 0, index);
    }

    newurl.setPath(path);
    return newurl;
}

QPoint KUrlNavigator::savedPosition() const
{
    const HistoryElem& histElem = d->m_history[d->m_historyIndex];
    return QPoint( histElem.contentsX(), histElem.contentsY() );
}

int KUrlNavigator::historySize() const
{
    return d->m_history.count();
}

void KUrlNavigator::goBack()
{
    d->updateHistoryElem();

    const int count = d->m_history.count();
    if (d->m_historyIndex < count - 1) {
        ++d->m_historyIndex;
        d->updateContent();
        emit urlChanged(url());
        emit historyChanged();
    }
}

void KUrlNavigator::goForward()
{
    if (d->m_historyIndex > 0) {
        --d->m_historyIndex;
        d->updateContent();
        emit urlChanged(url());
        emit historyChanged();
    }
}

void KUrlNavigator::goUp()
{
    setUrl(url().upUrl());
}

void KUrlNavigator::goHome()
{
    if (d->m_homeUrl.isEmpty())
        setUrl(QDir::homePath());
    else
        setUrl(d->m_homeUrl);
}

bool KUrlNavigator::isUrlEditable() const
{
    return d->m_toggleButton->isChecked();
}

void KUrlNavigator::setUrlEditable(bool editable)
{
    if (isUrlEditable() != editable) {
        d->m_toggleButton->toggle();
        d->switchView();
    }
}

void KUrlNavigator::setActive(bool active)
{
    if (active != d->m_active) {
        d->m_active = active;
        update();
        if (active) {
            emit activated();
        }
    }
}

void KUrlNavigator::setShowHiddenFiles( bool show )
{
    d->m_showHiddenFiles = show;
}

void KUrlNavigator::dropUrls(const KUrl::List& urls,
                            const KUrl& destination)
{
    emit urlsDropped(urls, destination);
}

void KUrlNavigator::setUrl(const KUrl& url)
{
    QString urlStr(url.pathOrUrl());

    // TODO: a patch has been submitted by Filip Brcic which adjusts
    // the URL for tar and zip files. See https://bugs.kde.org/show_bug.cgi?id=142781
    // for details. The URL navigator part of the patch has not been committed yet,
    // as the URL navigator will be subject of change and
    // we might think of a more generic approach to check the protocol + MIME type for
    // this use case.

    //kDebug() << "setUrl(" << url << ")" << endl;
    if ( urlStr.length() > 0 && urlStr.at(0) == '~') {
        // replace '~' by the home directory
        urlStr.remove(0, 1);
        urlStr.insert(0, QDir::homePath());
    }

    const KUrl transformedUrl(urlStr);

    if (d->m_historyIndex > 0) {
        // Check whether the previous element of the history has the same Url.
        // If yes, just go forward instead of inserting a duplicate history
        // element.
        HistoryElem& prevHistoryElem = d->m_history[d->m_historyIndex - 1];
        if (transformedUrl == prevHistoryElem.url()) {
            goForward();
//             kDebug() << "goin' forward in history" << endl;
            return;
        }
    }

    if (this->url() == transformedUrl) {
        // don't insert duplicate history elements
//         kDebug() << "current url == transformedUrl" << endl;
        return;
    }

    d->updateHistoryElem();
    d->m_history.insert(d->m_historyIndex, HistoryElem(transformedUrl));

    d->updateContent();

    emit urlChanged(transformedUrl);
    emit historyChanged();

    // Prevent an endless growing of the history: remembering
    // the last 100 Urls should be enough...
    if (d->m_historyIndex > 100) {
        d->m_history.removeFirst();
        --d->m_historyIndex;
    }

/*    kDebug() << "history starting ====================" << endl;
    int i = 0;
    for (QValueListIterator<KUrlNavigator::HistoryElem> it = d->m_history.begin();
         it != d->m_history.end();
         ++it, ++i)
    {
        kDebug() << i << ": " << (*it).url() << endl;
    }
    kDebug() << "history done ========================" << endl;*/

    requestActivation();
}

void KUrlNavigator::requestActivation()
{
    setActive(true);
}

void KUrlNavigator::storeContentsPosition(int x, int y)
{
    HistoryElem& hist = d->m_history[d->m_historyIndex];
    hist.setContentsX(x);
    hist.setContentsY(y);
}

void KUrlNavigator::keyReleaseEvent(QKeyEvent* event)
{
    QWidget::keyReleaseEvent(event);
    if (isUrlEditable() && (event->key() == Qt::Key_Escape)) {
        setUrlEditable(false);
    }
}

void KUrlNavigator::mouseReleaseEvent(QMouseEvent* event)
{
    if (event->button() == Qt::MidButton) {
        QClipboard* clipboard = QApplication::clipboard();
        const QMimeData* mimeData = clipboard->mimeData();
        if (mimeData->hasText()) {
            const QString text = mimeData->text();
            setUrl(KUrl(text));
        }
    }
    QWidget::mouseReleaseEvent(event);
}

bool KUrlNavigator::isActive() const
{
    return d->m_active;
}

bool KUrlNavigator::showHiddenFiles() const
{
    return d->m_showHiddenFiles;
}

void KUrlNavigator::setHomeUrl(const QString& homeUrl)
{
    d->m_homeUrl = homeUrl;
}

#include "kurlnavigator.moc"