#ifndef DB_MANAGER_H
#define DB_MANAGER_H

#include <sqlite3.h>
#include <QString>
#include <QList>
#include <QMap>
#include <QObject>
#include <cstdint>

struct ChannelRow {
    QString    channelId;
    QString    name;
    quint64    ownerNodeId = 0;
    QByteArray x25519_pubkey;
    QByteArray x25519_privkey;
    QByteArray ed25519_pubkey;
    QByteArray ed25519_privkey;
    QByteArray signature;               // Ed25519 подпись всех полей записи privkey канала

    qint64     lastReadMsgId = 0;
    qint64     lastPosMsgId = 0;
    qint64     createdAt = 0;
    int        unreadCount = 0;
};

struct MessageRow {
    qint64     id = 0;
    quint64    authorNodeId = 0;
    QString    contentType;
    QByteArray data;
    qint64     timestamp = 0;
    uint64_t   datahash = 0;
    QByteArray chainHash;
    QByteArray signature;
    bool       isOutgoing = false;
    bool       isRead = false;
};

struct AccountRow {
    quint64    nodeId = 0;
    QString    displayName;
    QString    avatarColor;
    QString    avatarLetter;
    bool       isContact = true;
};

struct ChannelMember {
    quint64 nodeId = 0;
    bool    online = false;
    QString name;       // from nodes.name, empty if not set
    QString localNick;  // from peers.local_nick override, empty if not set
};

struct NodeAddr {
    quint64    nodeId = 0;
    int        family = 0;
    int        protocol = 0;            // битмаска: 1=UDP, 2=TCP, 3=TCP+UDP
    QByteArray address;
    quint16    port = 0;
    int        rtt = 0;
    int        addrType = 0;            // ADDR_TYPE_*
    int        socketId = 0;            // socket_id из ETCP
};

struct IntegrityResult {
    bool        ok = false;
    QString     message;
    QStringList errors;
    int         elapsedMs = 0;
};

class DbManager : public QObject {
    Q_OBJECT
public:
    explicit DbManager(QObject* parent = nullptr);
    ~DbManager() override;

    bool    isOpen() const { return m_db != nullptr; }
    void    setDb(sqlite3* db) { m_db = db; }
    quint64 myNodeId() const { return m_myNodeId; }
    void    setMyNodeId(quint64 nodeId) { m_myNodeId = nodeId; }

    /* ── Каналы ── */
    QList<ChannelRow> getChannels() const;
    int  getUnreadCount(const QString& channelId, qint64 lastReadMsgId) const;

    /* ── UI state for channel read/scroll ── */
    qint64 getUiStateInt64(const QString& key, qint64 defaultVal = 0) const;

    /* ── Сообщения (UI) ── */
    QList<MessageRow> getMessages(const QString& chId, int limit = 50) const;
    QList<MessageRow> getMessagesSince(const QString& chId, qint64 sinceId) const;

    /* ── Участники канала (UI) ── */
    int  getChannelMemberCount(const QString& chId) const;
    QList<ChannelMember> getChannelMembers(const QString& chId, int offset, int limit) const;
    void cleanOrphanedPeers(const QString& chId) const;
    QString getDisplayName(quint64 nodeId) const;
    QMap<quint64, QString> getLocalNicknames(const QString& chId) const;

    /* ── Узлы ── */
    QByteArray loadNodeInfo(quint64 nodeId) const;
    QList<quint64> getOnlinePeers() const;
    QByteArray getNodeEdPub(quint64 nodeId) const;
    QList<NodeAddr> getOnlinePeerAddresses(quint64 excludeNodeId) const;

    /* ── Аккаунты ── */
    QList<AccountRow> getAccounts(bool contactsOnly = false) const;
    AccountRow getAccount(quint64 nodeId) const;

    /* ── UI state (read-only используем QSettings, оставлен для совместимости) ── */
    QString getUiState(const QString& key) const;
    int     getUiStateInt(const QString& key, int defaultVal) const;

    /* ── Sync-операции (read-only, для gui_bridge/inline) ── */
    QByteArray syncListChannels() const;
    QByteArray syncCount(const QString& chId) const;
    QByteArray syncChainHashAt(const QString& chId, uint32_t pos) const;
    QByteArray syncCursorOpen(const QString& chId);
    QByteArray syncCursorNext(uint32_t cursorId);
    void       syncCursorClose(uint32_t cursorId);
    QByteArray syncListPeers(const QString& chId) const;


    sqlite3_stmt* prepareOrNull(const char* sql) const;
    static QString    colText(sqlite3_stmt* stmt, int col);
    static QByteArray colBlob(sqlite3_stmt* stmt, int col);

    QString msgTableName(const QString& chId) const;
    QString peersTableName(const QString& chId) const;
    static QString sanitizeTableName(const QString& chId);
    static uint64_t computeDatahash(const QByteArray& data);
    static QByteArray computeChainHash(const QByteArray& prevChain,
                                       qint64 timestamp, uint64_t datahash);
    QByteArray getLastChainHash(const QString& chId) const;

    IntegrityResult integrityCheckQuick() const;
    IntegrityResult integrityCheckFull() const;
    IntegrityResult integrityOptimize() const;

    sqlite3* m_db = nullptr;
    quint64  m_myNodeId = 0;

    /* Кэш открытых курсоров для sync-операций */
    mutable QMap<uint32_t, sqlite3_stmt*> m_cursors;
    mutable uint32_t m_nextCursorId = 1;
};

#endif