/*
 * This file is part of the Flowee project
 * Copyright (C) 2025 Tom Zander <tom@flowee.org>
 *
 * This program 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.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef WALLETDATA_H
#define WALLETDATA_H

#include <QObject>

#include <Wallet.h>

#include <utils/streaming/ConstBuffer.h>
#include <utils/primitives/PrivateKey.h>
#include <utils/uint256.h>
#include <apputils/SimpleHttpClient.h>

class BackupSyncModuleInfo;

/*
 * This object monitors the Wallet for us.
 *
 * We like to upload data based on actual events, events that are
 * expected to change the save file, requiring a sync.
 */
class WalletData : public QObject
{
    Q_OBJECT
public:
    explicit WalletData(const std::shared_ptr<Wallet> &wallet, BackupSyncModuleInfo *parent);

    std::shared_ptr<Wallet> wallet() const;

    void setPrivKeyData(const Streaming::ConstBuffer &data);
    const PrivateKey &privKey() const;

    QString fancyAddess() const;

    void markDirty(); // needs save, but it immediately schedules an upload.
    bool needsSave() const;

    uint32_t lastSavedTime() const;
    void setLastSavedTime(uint32_t newLastSavedTime);

    enum RestoreReason {
        BeforeSave,
        JustRestore
    };

    // call this to ensure that we can call fancyAddess() later.
    bool deriveAuthKey();

signals:
    void lastSavedChanged();
    void restoreDone(bool success);

public slots:
    void upload();
    void restore(RestoreReason reason);

private slots:
    void onTxUpdated(int txIndex);
    void onTxConfirmed(int txIndex);
    void onTxAdded(int firstNew, int count);

private:
    struct SaveData {
        Streaming::ConstBuffer data;
        uint256 dataHash; // the unencrypted blob without the envelope
        uint32_t timestamp = 0;
    };

private slots:
    SaveData save();

private:
    void restoreFrom(const QString &savename);
    void restoreDownload(const Streaming::ConstBuffer &blob);


    BackupSyncModuleInfo *m_parent;
    uint256 m_lastSaveHash;
    std::shared_ptr<Wallet> m_wallet;
    PrivateKey m_privateKey;
    bool m_needsSave = false;
    uint32_t m_lastSavedTime = 0; // epoch style timestamp (UTC)
    std::shared_ptr<SimpleHttpClient> m_httpClient;
};

#endif