#ifndef PATCHDOWNLOADER_H
#define PATCHDOWNLOADER_H

#include <QObject>
#include <QList>
#include <QString>
#include <QMap>

#include "models/downloader.h"

class PatchDownloader : public QObject
{
    Q_OBJECT

public:
    static PatchDownloader& instance() {
        static PatchDownloader instance_;
        return instance_;
    }

    ~PatchDownloader();

private:
    Q_DISABLE_COPY(PatchDownloader)
    PatchDownloader();
    void downloadDatabases();         // Starts downloading all necessary patches.
    static bool needDownloadDatabase(QString db_name); // Checks if database needs to be downloaded (by checksum comparing)

public slots:
    void init();
    void checkForUpdates();  // Checks for updates
    void startPatchDownloaderChain();

signals:
    void started();
    void progressChanged(Downloader::Status status);
    void finished();

private slots:
    void onDownloaderProgressChanged(Downloader* context, Downloader::Status progress);
    void onDownloaderFinished(Downloader* context);

private:
    bool started_ = false;
    const QList<QString> patches_ = {"text", "font", "image", "texture", "loadscreen", "sound", "video"};
    QMap<QString, Downloader*> patch_downloaders_;
    QMap<Downloader*, Downloader::Status> patch_downloaders_status_;
};

#endif // PATCHDOWNLOADER_H