// This file is part of RSS Guard.
//
// Copyright (C) 2011-2015 by Martin Rotter <rotter.martinos@gmail.com>
//
// RSS Guard 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 3 of the License, or
// (at your option) any later version.
//
// RSS Guard 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 RSS Guard. If not, see <http://www.gnu.org/licenses/>.

#ifndef FEEDSMODELFEED_H
#define FEEDSMODELFEED_H

#include "core/feedsmodelrootitem.h"

#include <QMetaType>
#include <QDateTime>
#include <QSqlRecord>
#include <QPair>
#include <QNetworkReply>
#include <QCoreApplication>


class Message;

// Represents BASE class for feeds contained in FeedsModel.
// NOTE: This class should be derived to create PARTICULAR feed types.
class FeedsModelFeed : public FeedsModelRootItem {
    Q_DECLARE_TR_FUNCTIONS(FeedsModelFeed)

  public:
    // Describes possible types of feeds.
    // NOTE: This is equivalent to attribute Feeds(type).
    enum Type {
      Rss0X   = 0,
      Rss2X   = 1,
      Rdf     = 2,  // Sometimes denoted as RSS 1.0.
      Atom10  = 3
    };

    // Specifies the auto-update strategy for the feed.
    enum AutoUpdateType {
      DontAutoUpdate      = 0,
      DefaultAutoUpdate   = 1,
      SpecificAutoUpdate  = 2
    };

    // Specifies the actual "status" of the feed.
    // For example if it has new messages, error
    // occurred, and so on.
    enum Status {
      Normal        = 0,
      NewMessages   = 1,
      NetworkError  = 2
    };

    // Constructors and destructors.
    explicit FeedsModelFeed(FeedsModelRootItem *parent_item = NULL);
    explicit FeedsModelFeed(const FeedsModelFeed &other);
    explicit FeedsModelFeed(const QSqlRecord &record);
    virtual ~FeedsModelFeed();

    // Returns 0, feeds have no children.
    int childCount() const;

    // Getters/setters for count of messages.
    // NOTE: For feeds, counts are stored internally
    // and can be updated from the database.
    int countOfAllMessages() const;
    int countOfUnreadMessages() const;

    // Obtains data related to this feed.
    QVariant data(int column, int role) const;

    // Perform fetching of new messages.
    void update();

    // Removes this standard feed from persistent
    // storage.
    bool removeItself();

    // Other getters/setters.
    inline Type type() const {
      return m_type;
    }

    inline void setType(const Type &type) {
      m_type = type;
    }

    inline bool passwordProtected() const {
      return m_passwordProtected;
    }

    inline void setPasswordProtected(bool passwordProtected) {
      m_passwordProtected = passwordProtected;
    }

    inline QString username() const {
      return m_username;
    }

    inline void setUsername(const QString &username) {
      m_username = username;
    }

    inline QString password() const {
      return m_password;
    }

    inline void setPassword(const QString &password) {
      m_password = password;
    }

    inline QString encoding() const {
      return m_encoding;
    }

    inline void setEncoding(const QString &encoding) {
      m_encoding = encoding;
    }

    inline QString url() const {
      return m_url;
    }

    inline void setUrl(const QString &url) {
      m_url = url;
    }

    inline int autoUpdateInitialInterval() const {
      return m_autoUpdateInitialInterval;
    }

    inline void setAutoUpdateInitialInterval(int auto_update_interval) {
      // If new initial auto-update interval is set, then
      // we should reset time that remains to the next auto-update.
      m_autoUpdateInitialInterval = auto_update_interval;
      m_autoUpdateRemainingInterval = auto_update_interval;
    }

    inline AutoUpdateType autoUpdateType() const {
      return m_autoUpdateType;
    }

    inline void setAutoUpdateType(const AutoUpdateType &autoUpdateType) {
      m_autoUpdateType = autoUpdateType;
    }

    inline int autoUpdateRemainingInterval() const {
      return m_autoUpdateRemainingInterval;
    }

    inline void setAutoUpdateRemainingInterval(int autoUpdateRemainingInterval) {
      m_autoUpdateRemainingInterval = autoUpdateRemainingInterval;
    }

    inline Status status() const {
      return m_status;
    }

    inline void setStatus(const Status &status) {
      m_status = status;
    }

    QNetworkReply::NetworkError networkError() const;

    // Tries to guess feed hidden under given URL
    // and uses given credentials.
    // Returns pointer to guessed feed (if at least partially
    // guessed) and retrieved error/status code from network layer
    // or NULL feed.
    static QPair<FeedsModelFeed*, QNetworkReply::NetworkError> guessFeed(const QString &url,
                                                                         const QString &username,
                                                                         const QString &password);

    // Converts particular feed type to string.
    static QString typeToString(Type type);

  public slots:
    // Updates counts of all/unread messages for this feed.
    void updateCounts(bool including_total_count = true, bool update_feed_statuses = true);

  protected:
    // Persistently stores given messages into the database
    // and updates existing messages if newer version is
    // available.
    void updateMessages(const QList<Message> &messages);

  private:
    void init();

  private:    
    bool m_passwordProtected;
    QString m_username;
    QString m_password;

    Status m_status;
    QNetworkReply::NetworkError m_networkError;
    Type m_type;
    int m_totalCount;
    int m_unreadCount;

    AutoUpdateType m_autoUpdateType;
    int m_autoUpdateInitialInterval;
    int m_autoUpdateRemainingInterval;

    QString m_encoding;
    QString m_url;
};

Q_DECLARE_METATYPE(FeedsModelFeed::Type)

#endif // FEEDSMODELFEED_H