/* ============================================================
*
* This file is a part of the rekonq project
*
* Copyright (C) 2009 by Andrea Diamantini <adjam7 at gmail dot 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) version 3 or any later version
* accepted by the membership of KDE e.V. (or its successor approved
* by the membership of KDE e.V.), which shall act as a proxy 
* defined in Section 14 of version 3 of the license.
* 
* 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, see <http://www.gnu.org/licenses/>.
*
* ============================================================ */


// Self Includes
#include "previewimage.h"
#include "previewimage.moc"

// Local Includes
#include "historymanager.h"
#include "rekonq.h"
#include "mainwindow.h"
#include "mainview.h"

// KDE Includes
#include <KUrl>
#include <KStandardDirs>
#include <KDebug>
#include <KMenu>
#include <KAction>
#include <KLocale>

// Qt Includes
#include <QFile>
#include <QMovie>
#include <QMouseEvent>
#include <QHBoxLayout>
#include <QVBoxLayout>
#include <QPainter>


PreviewImage::PreviewImage(const QUrl &url, const QString &title, int index, bool isFavorite)
    : QWidget()
    , ws(0)
    , loadingSnapshot(false)
    , m_url(url)
    , m_title(title)
    , m_isFavorite(isFavorite)
    , m_index(index)
    , m_button(0)
    , m_imageLabel(new QLabel)
    , m_textLabel(new QLabel)
    , m_backgroundLabel(new QLabel)
    , m_previewLabel(new QLabel)
{

    int borderTop = 14;
    int borderRight = 16;
    int borderBottom = 14;
    int borderLeft = 16;

    int previewWidth = 200;
    int previewHeight = 150;

    int urlHeight = 18;

    m_size = QSize(borderLeft+previewWidth+borderRight, borderTop+previewHeight+borderBottom+urlHeight);

    setFixedSize(m_size);
    m_previewLabel->setFixedSize(m_size);

    m_backgroundLabel->setPixmap(renderBackground(previewWidth,previewHeight, borderTop, borderBottom, borderLeft, borderRight));

    m_previewLabel->setAlignment(Qt::AlignCenter);
    m_backgroundLabel->setAlignment(Qt::AlignCenter);
    m_imageLabel->setAlignment(Qt::AlignCenter);
    m_textLabel->setAlignment(Qt::AlignCenter);

    m_previewLabel->setLayout(new QVBoxLayout);
    m_previewLabel->layout()->setMargin(0);
    m_previewLabel->layout()->addWidget(m_backgroundLabel);
    m_previewLabel->layout()->addWidget(m_textLabel);
    m_previewLabel->setCursor(Qt::PointingHandCursor);

    m_backgroundLabel->setLayout(new QVBoxLayout);
    m_backgroundLabel->layout()->addWidget(m_imageLabel);

    setLayout(new QHBoxLayout);
    layout()->setMargin(0);
    layout()->setAlignment(Qt::AlignCenter);
    layout()->addWidget(m_previewLabel);

    connect(this, SIGNAL(loadUrl(const KUrl &, const Rekonq::OpenType &)), 
            Application::instance(), SLOT(loadUrl(const KUrl &, const Rekonq::OpenType &)));
    
    loadUrlPreview(url);
}


PreviewImage::~PreviewImage()
{
    delete ws;
    delete m_textLabel;
    delete m_imageLabel;
    delete m_backgroundLabel;
    delete m_previewLabel;
}


QPixmap PreviewImage::renderBackground(int w, int h, int t, int b, int l, int r)
{
    QImage backImage(KStandardDirs::locate("appdata", "pics/bg.png"));
    QImage resultImage(QSize(w + l + r, h + t + b), QImage::Format_ARGB32_Premultiplied);

    if (!backImage.isNull())
    {
        int sw = backImage.width() - l - r;
        int sh = backImage.height() - t - b;
        QPainter pt(&resultImage);
        pt.setCompositionMode(QPainter::CompositionMode_Source);
        pt.fillRect(resultImage.rect(), Qt::transparent);
        pt.drawImage(QRect(0, 0, l, t), backImage, QRect(0, 0, l, t));
        pt.drawImage(QRect(l, 0, w, t), backImage, QRect(l, 0, sw, t));
        pt.drawImage(QRect(l + w, 0, r, t), backImage, QRect(l + sw, 0, r, t));
        pt.drawImage(QRect(0, t, l, h), backImage, QRect(0, t, l, sh));
        pt.drawImage(QRect(l, t, w, h), backImage, QRect(l, t, sw, sh));
        pt.drawImage(QRect(l + w, t, r, h), backImage, QRect(l + sw, t, r, sh));
        pt.drawImage(QRect(0, t + h, l , b), backImage, QRect(0, t + sh, l , b));
        pt.drawImage(QRect(l, t + h, w, b), backImage, QRect(l, t + sh, sw, b));
        pt.drawImage(QRect(l + w, t + h, w, b), backImage, QRect(l + sw, t + sh, sw, b));
        pt.end();
    }

    return QPixmap::fromImage(resultImage);
}


void PreviewImage::loadUrlPreview(const QUrl& url)
{
    m_url = url;

    if(url.isEmpty())
    {
        showEmptyPreview();
        return;
    }

    m_previewLabel->setFixedSize(m_size); //unhide

    m_savePath = KStandardDirs::locateLocal("cache", QString("thumbs/") + guessNameFromUrl(m_url) + ".png", true);

    if(QFile::exists(m_savePath))
    {
        m_pixmap.load(m_savePath);
        m_imageLabel->setPixmap(m_pixmap);
        checkTitle();
        m_textLabel->setText(m_title);
    }
    else
    {
        loadingSnapshot = true;
        ws = new WebSnap( url );
        connect(ws, SIGNAL(finished()), this, SLOT(snapFinished()));

        QString path = KStandardDirs::locate("appdata", "pics/busywidget.gif");

        // load an animation waiting for site preview
        QMovie *movie = new QMovie(path, QByteArray(), this);
        movie->setSpeed(50);
        m_imageLabel->setMovie(movie);
        movie->start();
        m_textLabel->setText( i18n("Loading preview...") );
        setCursor(Qt::BusyCursor);
    }
}


void PreviewImage::snapFinished()
{
    loadingSnapshot = false;
    QMovie *m = m_imageLabel->movie();
    delete m;
    m_imageLabel->setMovie(0);

    m_pixmap = ws->previewImage();
    m_imageLabel->setPixmap(m_pixmap);
    checkTitle();
    m_textLabel->setText(m_title);

    setCursor(Qt::PointingHandCursor);

    m_pixmap.save(m_savePath);

    if(m_index > -1)
    {
        // Update title
        QStringList names = ReKonfig::previewNames();
        // update url (for added thumbs)
        QStringList urls = ReKonfig::previewUrls();

        // stripTrailingSlash to be sure to get the same string for same address
        urls.replace(m_index, ws->snapUrl().toString(QUrl::StripTrailingSlash));
        names.replace(m_index, ws->snapTitle());

        ReKonfig::setPreviewNames(names);
        ReKonfig::setPreviewUrls(urls);

        ReKonfig::self()->writeConfig();
    }
}


void PreviewImage::showEmptyPreview()
{
    if(!m_isFavorite)
        return;

    m_imageLabel->clear();
    m_textLabel->clear();

    m_previewLabel->setFixedSize(0,0); //hide


    m_button = new QToolButton();
    m_button->setDefaultAction(historyMenu());
    m_button->setPopupMode(QToolButton::InstantPopup);
    m_button->setToolButtonStyle(Qt::ToolButtonTextUnderIcon);
    m_button->setText(i18n("Add Preview"));
    m_button->setAutoRaise(true);
    m_button->setIconSize(QSize(48, 48));
    layout()->addWidget(m_button);
}


void PreviewImage::mouseDoubleClickEvent(QMouseEvent *event)
{
    kDebug() << "no double click over here, thanks :D";
    Q_UNUSED(event);
}


void PreviewImage::mouseMoveEvent(QMouseEvent *event)
{
    kDebug() << "moving mouse over preview image";
    Q_UNUSED(event)
}


void PreviewImage::mousePressEvent(QMouseEvent *event)
{
    if(event->button() == Qt::LeftButton)
    {
        emit loadUrl(m_url, Rekonq::CurrentTab);
        return;
    }
    else if(event->button() == Qt::MidButton)
    {
        emit loadUrl(m_url, Rekonq::SettingOpenTab);
        return;
    }

    QWidget::mousePressEvent(event);
}


void PreviewImage::mouseReleaseEvent(QMouseEvent *event)
{
    kDebug() << "NO000... don't leave your finger from the button!!";
    Q_UNUSED(event)
}


void PreviewImage::contextMenuEvent(QContextMenuEvent* event)
{
    if(!m_isFavorite)
        return;

    if(loadingSnapshot)
       return;

    KMenu menu(this);
    KAction *a;

    if(!m_url.isEmpty())
    {
        a = new KAction(KIcon("edit-delete"), i18n("Remove Thumbnail"), this);
        connect(a, SIGNAL(triggered(bool)), this, SLOT(removeMe()));
        menu.addAction(a);

        a = new KAction(KIcon("view-refresh"), i18n("Refresh Thumbnail"), &menu);
        connect(a, SIGNAL(triggered(bool)), this, SLOT(refreshPreview()));
        menu.addAction(a);
    }
    menu.addAction(historyMenu());

    menu.exec(mapToGlobal(event->pos()));
}


KActionMenu* PreviewImage::historyMenu()
{
    KActionMenu *histMenu = new KActionMenu(KIcon("insert-image"), i18n("Set Page to Preview"), this);
    QList<HistoryItem> history =  Application::historyManager()->history();

    if(history.isEmpty())
    {
        KAction *a = new KAction(i18n("History is Empty"), this);
        a->setEnabled(false);
        histMenu->addAction(a);
        return histMenu;
    }

    int maxItems = 15;
    for (int i = 0; i < maxItems && i < history.size() ; ++i) 
    {
        HistoryItem it = history.at(i);
        KAction *a = new KAction(Application::icon(it.url), it.title, this);
        QStringList urlData;
        urlData << it.url << it.title;
        a->setData(urlData);
        connect(a, SIGNAL(triggered(bool)), this, SLOT(setUrlFromAction()));
        histMenu->addAction(a);
    }

    return histMenu;
}


void PreviewImage::removeMe()
{
    QStringList names = ReKonfig::previewNames();
    QStringList urls = ReKonfig::previewUrls();

    int index = urls.indexOf(QRegExp(m_url.toString(QUrl::StripTrailingSlash), Qt::CaseSensitive, QRegExp::FixedString));

    urls.replace(index, QString(""));
    names.replace(index, QString(""));

    ReKonfig::setPreviewNames(names);
    ReKonfig::setPreviewUrls(urls);

    // sync file data
    ReKonfig::self()->writeConfig();

    showEmptyPreview();

    m_url = "";
}


void PreviewImage::setUrlFromAction()
{
    KAction *a = qobject_cast<KAction*>(sender());
    QStringList urlData = a->data().toStringList();

    m_url = KUrl(urlData.at(0));
    m_title = urlData.at(1);
    checkTitle();

    if(m_button)
    {
        m_imageLabel->layout()->deleteLater();
        m_button->menu()->deleteLater();
        m_button->deleteLater();
    }
    loadUrlPreview(m_url);

    // Update title
    QStringList names = ReKonfig::previewNames();
    // update url (for added thumbs)
    QStringList urls = ReKonfig::previewUrls();

    // stripTrailingSlash to be sure to get the same string for same address
    urls.replace(m_index, m_url.toString(QUrl::StripTrailingSlash));
    names.replace(m_index, m_title);

    ReKonfig::setPreviewNames(names);
    ReKonfig::setPreviewUrls(urls);

    ReKonfig::self()->writeConfig();
}


void PreviewImage::refreshPreview()
{
    QString path = KStandardDirs::locateLocal("cache", QString("thumbs/") + guessNameFromUrl(m_url) + ".png", true);
    QFile::remove(path);
    loadUrlPreview(m_url);
}


QString PreviewImage::guessNameFromUrl(QUrl url)
{
    QString name = url.toString( QUrl::RemoveScheme | QUrl::RemoveUserInfo | QUrl::StripTrailingSlash );

    // TODO learn Regular Expressions :)
    // and implement something better here..
    name.remove('/');
    name.remove('&');
    name.remove('.');
    name.remove('-');
    name.remove('_');
    name.remove('?');
    name.remove('=');
    name.remove('+');

    return name;
}


void PreviewImage::checkTitle()
{
    if(m_title.length() > 23)
    {
        m_title.truncate(20);
        m_title += "...";
    }
}