/*
    Copyright (c) 2016 Michael Bohlender <michael.bohlender@kdemail.net>
    Copyright (c) 2016 Christian Mollekopf <mollekopf@kolabsys.com>

    This library is free software; you can redistribute it and/or modify it
    under the terms of the GNU Library General Public License as published by
    the Free Software Foundation; either version 2 of the License, or (at your
    option) any later version.

    This library 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 Library General Public
    License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to the
    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301, USA.
*/

#pragma once

#include <sink/applicationdomaintype.h>

#include <QAbstractItemModel>
#include <QList>
#include <QSharedPointer>
#include <QVector>

// Implementation notes
// ====================
//
// On the model side
// -----------------
//
// Columns are never used.
//
// Top-level items just contains the ".events" attribute, and their rows
// correspond to their day of week. In that case the internalId contains
// DAY_ID.
//
// Direct children are events, and their rows corresponds to their index in
// their partition. In that case no internalId / internalPointer is used.
//
// Internally:
// -----------
//
// On construction and on dataChanged, all events are processed and partitioned
// in partitionedEvents:
//
// QVector< QList<QSharedPointer<Event> >
// ~~~~~~~  ~~~~~~~~~~~~~~~~~~~~~~~~~~~
//    |                |
//    |                '--- List of event pointers for that day
//    '--- Partition / day
//
class EventTreeModel : public QAbstractItemModel
{
    Q_OBJECT

public:
    using Event = Sink::ApplicationDomain::Event;

    enum Roles
    {
        Events = Qt::UserRole + 1,
        Summary,
        Description,
        StartTime,
        Duration,
    };
    Q_ENUM(Roles);
    EventTreeModel(QObject *parent = nullptr);
    ~EventTreeModel() = default;

    QModelIndex index(int row, int column, const QModelIndex &parent = {}) const override;
    QModelIndex parent(const QModelIndex &index) const override;

    int rowCount(const QModelIndex &parent) const override;
    int columnCount(const QModelIndex &parent) const override;

    bool hasChildren(const QModelIndex &parent) const override;

    QVariant data(const QModelIndex &index, int role) const override;

    QHash<int, QByteArray> roleNames() const override;

private:
    void partitionData();

    QSharedPointer<QAbstractItemModel> eventModel;
    QVector<QList<QSharedPointer<Event>>> partitionedEvents;

    static const constexpr quintptr DAY_ID = 7;
};