/*******************************************************************************
**
** SPDX-FileCopyrightText: Copyright 2023 Open Mobile Platform LLC <community@omp.ru>
** SPDX-License-Identifier: BSD-3-Clause
** This file is part of the OfficeViewer project.
**
** Redistribution and use in source and binary forms,
** with or without modification, are permitted provided
** that the following conditions are met:
**
** * Redistributions of source code must retain the above copyright notice,
**   this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright notice,
**   this list of conditions and the following disclaimer
**   in the documentation and/or other materials provided with the distribution.
** * Neither the name of the copyright holder nor the names of its contributors
**   may be used to endorse or promote products derived from this software
**   without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
** THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
** FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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** OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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*******************************************************************************/

#pragma once

#include "documentproviderglobal.h"
#include <atomic>
#include <QFileInfo>
#include <QImage>
#include <QMap>
#include <QMutex>
#include <QObject>
#include <QThreadPool>

class CopyWorker : public QObject, public QRunnable
{
    Q_OBJECT
        public:
    CopyWorker(const QString &pathFrom, const QString &pathTo)
        : pathFrom(pathFrom)
        , pathTo(pathTo)
    {}

signals:
    void ready(bool status);

private:
    void run() override
    {
        QFile::remove(pathTo);
        emit ready(QFile::copy(pathFrom, pathTo));
    }

    QString pathFrom;
    QString pathTo;
};


class DOCUMENTPROVIDER_EXPORT ExportedCache : public QObject
{
    Q_OBJECT

public:
    struct CacheKey
    {
        CacheKey(const QString &fileId, const QString &format)
            : fileId(fileId)
            , format(format)
        {}

        bool operator==(const CacheKey &other) const
        {
            return fileId == other.fileId && format == other.format;
        }

        QString fileId;
        QString format;
    };

public:
    ExportedCache(const QString &pathCache, QObject *parent = nullptr);

    ~ExportedCache();

    bool loadExportedDoc(const QString &fileId, const QString &pathExportedDoc, const QString &format = "pdf");
    void insertExportedDoc(const QString &fileId, const QString &pathExportedDoc, const QString &format = "pdf");

    void loadCache();
    void writeInList(const QString &fileId, const QString &format);
    QString makeCachePath(quint32 hash);

signals:
    void documentExported(const QString &pathExportedDoc, const QString format, bool status);
    void checksumCalculated(const QString &filePath, const QByteArray &checksum);

private:
    QString m_path;
    qint64 m_limit;            // bytes
    qint64 m_currentCacheSize; // bytes
    QHash<quint32, QFileInfo> m_cache;
    QMap<QDateTime, quint32> m_cacheSortedByCreated;
    QHash<CacheKey, QImage> m_writeQueue;
    std::atomic_bool m_loading;
    QThreadPool m_threadPool;
    QMutex m_mutex;
};