/* ============================================================
*
* This file is a part of the rekonq project
*
* Copyright (C) 2007-2008 Trolltech ASA. All rights reserved
* Copyright (C) 2008 Benjamin C. Meyer <ben@meyerhome.net>
* Copyright (C) 2008-2012 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/>.
*
* ============================================================ */


#ifndef HISTORY_H
#define HISTORY_H


// KDE Includes
#include <KUrl>

// Qt Includes
#include <QDateTime>
#include <QHash>
#include <QObject>
#include <QWebHistory>

#include <math.h>

// Forward Declarations
class AutoSaver;
class HistoryFilterModel;
class HistoryTreeModel;

class QWebHistory;


/**
 * Elements in this class represent an history item
 *
 */
class HistoryItem
{
public:
    HistoryItem() : visitCount(1)
    {}

    explicit HistoryItem(const QString &u,
                         const QDateTime &d = QDateTime(),
                         const QString &t = QString()
                        )
        : title(t)
        , url(u)
        , firstDateTimeVisit(d)
        , lastDateTimeVisit(d)
        , visitCount(1)
    {}

    inline bool operator==(const HistoryItem &other) const
    {
        return other.title == title
               && other.url == url
               && other.firstDateTimeVisit == firstDateTimeVisit
               && other.lastDateTimeVisit == lastDateTimeVisit;
    }

    inline qreal relevance() const
    {
        return log(visitCount) - log(lastDateTimeVisit.daysTo(QDateTime::currentDateTime()) + 1);
    }

    // history is sorted in reverse
    // WARNING: Please, NO MORE CHANGE this!
    inline bool operator <(const HistoryItem &other) const
    {
        return lastDateTimeVisit > other.lastDateTimeVisit;
    }

    QString title;
    QString url;
    QDateTime firstDateTimeVisit;
    QDateTime lastDateTimeVisit;
    int visitCount;
};


// ---------------------------------------------------------------------------------------------------------------


/**
 * THE History Manager:
 * It manages rekonq history
 *
 */
class HistoryManager : public QObject
{
    Q_OBJECT

public:
    /**
     * Entry point.
     * Access to HistoryManager class by using
     * HistoryManager::self()->thePublicMethodYouNeed()
     */
    static HistoryManager *self();

    ~HistoryManager();

    bool historyContains(const QString &url) const;
    void addHistoryEntry(const KUrl &url, const QString &title);
    void removeHistoryEntry(const KUrl &url, const QString &title = QString());
    void removeHistoryLocationEntry(int value);

    QList<HistoryItem> find(const QString &text);

    QList<HistoryItem> history() const
    {
        return m_history;
    };
    void setHistory(const QList<HistoryItem> &history, bool loadedAndSorted = false);

    // History manager keeps around these models for use by the completer and other classes
    HistoryFilterModel *historyFilterModel() const
    {
        return m_historyFilterModel;
    };
    HistoryTreeModel *historyTreeModel() const
    {
        return m_historyTreeModel;
    };

Q_SIGNALS:
    void historyReset();
    void entryAdded(const HistoryItem &item);
    void entryRemoved(const HistoryItem &item);

    void historySaved();

public Q_SLOTS:
    void clear();
    void loadSettings();

private Q_SLOTS:
    void save();
    void checkForExpired();

private:
    HistoryManager(QObject *parent = 0);
    void load();

    AutoSaver *m_saveTimer;
    int m_historyLimit;
    QList<HistoryItem> m_history;
    QString m_lastSavedUrl;

    HistoryFilterModel *m_historyFilterModel;
    HistoryTreeModel *m_historyTreeModel;

    static QWeakPointer<HistoryManager> s_historyManager;
};


#endif // HISTORY_H