/*
    SPDX-FileCopyrightText: 2007 Joris Guisson <joris.guisson@gmail.com>
    SPDX-FileCopyrightText: 2007 Ivan Vasic <ivasic@gmail.com>
    SPDX-License-Identifier: GPL-2.0-or-later
*/

#ifndef KTTORRENTFILETREEMODEL_H
#define KTTORRENTFILETREEMODEL_H

#include "torrentfilemodel.h"
#include <util/bitset.h>

class QSortFilterProxyModel;

namespace bt
{
class BEncoder;
class BNode;
}

namespace kt
{
/**
 * Model for displaying file trees of a torrent
 * @author Joris Guisson
 */
class KTCORE_EXPORT TorrentFileTreeModel : public TorrentFileModel
{
    Q_OBJECT
protected:
    struct KTCORE_EXPORT Node {
        Node *parent;
        bt::TorrentFileInterface *file; // file (0 if this is a directory)
        QString name; // name or directory
        QList<Node *> children; // child dirs
        bt::Uint64 size;
        bt::BitSet chunks;
        bool chunks_set;
        float percentage;

        Node(Node *parent, bt::TorrentFileInterface *file, const QString &name, bt::Uint32 total_chunks);
        Node(Node *parent, const QString &name, bt::Uint32 total_chunks);
        ~Node();

        void insert(const QString &path, bt::TorrentFileInterface *file, bt::Uint32 num_chunks);
        int row();
        bt::Uint64 fileSize(const bt::TorrentInterface *tc);
        bt::Uint64 bytesToDownload(const bt::TorrentInterface *tc);
        Qt::CheckState checkState(const bt::TorrentInterface *tc) const;
        QString path();
        void fillChunks();
        void updatePercentage(const bt::BitSet &havechunks);
        void initPercentage(const bt::TorrentInterface *tc, const bt::BitSet &havechunks);

        /**
         * Save the expanded state of the tree
         * @param index The index that belongs to the real model and refers to this Node
         * @param real_model The real model that owns this Node
         * @param pm Proxy model of the view
         * @param tv The QTreeView
         * @param enc The current state of the tree expansion
         */
        void saveExpandedState(const QModelIndex &index, TorrentFileTreeModel *real_model, QSortFilterProxyModel *pm, QTreeView *tv, bt::BEncoder *enc) const;

        /**
         * Restore the expanded state of the tree
         * @param index The index that belongs to the real model and refers to this Node
         * @param real_model The real model that owns this Node
         * @param pm Proxy model of the view
         * @param tv The QTreeView
         * @param enc The BEncoded node that refers to this Node's expansion state
         */
        void loadExpandedState(const QModelIndex &index, TorrentFileTreeModel *real_model, QSortFilterProxyModel *pm, QTreeView *tv, bt::BNode *node) const;
    };

public:
    TorrentFileTreeModel(bt::TorrentInterface *tc, DeselectMode mode, QObject *parent);
    ~TorrentFileTreeModel() override;

    void changeTorrent(bt::TorrentInterface *tc) override;
    int rowCount(const QModelIndex &parent) const override;
    int columnCount(const QModelIndex &parent) const override;
    QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
    QVariant data(const QModelIndex &index, int role) const override;
    QModelIndex parent(const QModelIndex &index) const override;
    QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override;
    bool setData(const QModelIndex &index, const QVariant &value, int role) override;
    void checkAll() override;
    void uncheckAll() override;
    void invertCheck() override;
    bt::Uint64 bytesToDownload() override;
    QByteArray saveExpandedState(QSortFilterProxyModel *pm, QTreeView *tv) override;
    void loadExpandedState(QSortFilterProxyModel *pm, QTreeView *tv, const QByteArray &state) override;
    bt::TorrentFileInterface *indexToFile(const QModelIndex &idx) override;
    QString dirPath(const QModelIndex &idx) override;
    void changePriority(const QModelIndexList &indexes, bt::Priority newpriority) override;
    void onCodecChange() override;

protected:
    bool setName(const QModelIndex &index, const QString &name);

private:
    void constructTree();
    void invertCheck(const QModelIndex &idx);
    bool setCheckState(const QModelIndex &index, Qt::CheckState state);
    void modifyPathOfFiles(Node *n, const QString &path);

protected:
    Node *root;
    bool emit_check_state_change;
};

}

#endif
