13. 数据库、DBMgr 与持久化

// 文件：kbe/src/server/dbmgr/dbmgr.h（简化）
class Dbmgr : public PythonApp, public Singleton<Dbmgr>
{
public:
    // 实体操作
    void writeEntity(Network::Channel* pChannel, MemoryStream& s);
    void removeEntity(Network::Channel* pChannel, MemoryStream& s);
    void queryEntity(Network::Channel* pChannel, uint16 dbInterfaceIndex,
        COMPONENT_ID componentID, int8 queryMode, DBID dbid,
        std::string& entityType, CALLBACK_ID callbackID, ENTITY_ID entityID);

    // 账号操作
    void reqCreateAccount(Network::Channel* pChannel, MemoryStream& s);
    void onAccountLogin(Network::Channel* pChannel, MemoryStream& s);

    // ID 分配
    void onReqAllocEntityID(Network::Channel* pChannel,
        COMPONENT_ORDER componentType, COMPONENT_ID componentID);

    // 原始 SQL
    void executeRawDatabaseCommand(Network::Channel* pChannel, MemoryStream& s);

private:
    IDServer<ENTITY_ID> idServer_;                     // 实体 ID 分配服务
    BUFFERED_DBTASKS_MAP bufferedDBTasksMaps_;          // 任务缓冲区
    GlobalDataServer* pGlobalData_;                     // 全局数据
    GlobalDataServer* pBaseAppData_;                    // BaseApp 共享数据
    GlobalDataServer* pCellAppData_;                    // CellApp 共享数据

    uint32 numWrittenEntity_;
    uint32 numRemovedEntity_;
    uint32 numQueryEntity_;
};

// 通用基类：kbe/src/lib/db_interface/db_tasks.h
class DBTaskBase : public thread::TPTask
{
public:
    virtual bool process();
    virtual bool db_thread_process() = 0;
    virtual thread::TPTask::TPTaskState presentMainThread();
};

// DBMgr 专用实体任务：kbe/src/server/dbmgr/dbtasks.h
class EntityDBTask : public DBTaskBase
{
    // 额外带 entityID / dbid / 回包地址
};

class DBTaskWriteEntity : public EntityDBTask
{
    bool db_thread_process();
    TPTaskState presentMainThread();
};

// 文件：kbe/src/lib/db_interface/entity_table.h（简化）
class EntityTable
{
public:
    virtual bool initialize(ScriptDefModule* sm, std::string name) = 0;
    virtual bool syncToDB(DBInterface* pdbi) = 0;          // 同步表结构到 DB
    virtual bool syncIndexToDB(DBInterface* pdbi) = 0;     // 同步索引

    DBID writeTable(DBInterface* pdbi, DBID dbid,
        int8 shouldAutoLoad, MemoryStream* s, ScriptDefModule* pModule);
    bool removeEntity(DBInterface* pdbi, DBID dbid, ScriptDefModule* pModule);
    bool queryTable(DBInterface* pdbi, DBID dbid,
        MemoryStream* s, ScriptDefModule* pModule);

    // 序列化/反序列化
    void addPersistentsDataToStream(MemoryStream* s, ...);
    void createDictDataFromPersistentStream(MemoryStream* s, ...);

protected:
    std::string name_;                    // 表名
    TABLE_ITEM_MAP tableItems_;           // 列描述
    uint32 uid_;                          // 表 UID
};

// 每个 .def 属性类型对应一个 EntityTableItem
#define TABLE_ITEM_TYPE_FIXEDARRAY   1   // → MySQL TEXT/BLOB
#define TABLE_ITEM_TYPE_FIXEDDICT    2   // → MySQL TEXT/BLOB
#define TABLE_ITEM_TYPE_STRING       3   // → MySQL VARCHAR/TEXT
#define TABLE_ITEM_TYPE_DIGIT        4   // → MySQL INT/BIGINT
#define TABLE_ITEM_TYPE_BLOB         5   // → MySQL BLOB
#define TABLE_ITEM_TYPE_VECTOR2      6   // → MySQL FLOAT, FLOAT
#define TABLE_ITEM_TYPE_VECTOR3      7   // → MySQL FLOAT, FLOAT, FLOAT
#define TABLE_ITEM_TYPE_VECTOR4      8   // → MySQL FLOAT, FLOAT, FLOAT, FLOAT
#define TABLE_ITEM_TYPE_UNICODE      9   // → MySQL TEXT
#define TABLE_ITEM_TYPE_PYTHON      11   // → MySQL BLOB（pickle）

// 文件：kbe/src/lib/db_mysql/entity_table_mysql.h（简化）
class EntityTableMysql : public EntityTable
{
    DBID writeTable(DBInterface* pdbi, DBID dbid,
        int8 shouldAutoLoad, MemoryStream* s, ScriptDefModule* pModule);
    bool removeEntity(DBInterface* pdbi, DBID dbid, ScriptDefModule* pModule);
    bool queryTable(DBInterface* pdbi, DBID dbid,
        MemoryStream* s, ScriptDefModule* pModule);
};

class EntityTableItemMysql_VECTOR3 : public EntityTableItemMysqlBase
{
    uint8 type() const { return TABLE_ITEM_TYPE_VECTOR3; }
    void getWriteSqlItem(DBInterface* pdbi, MemoryStream* s,
        mysql::DBContext& context);
    // VECTOR3 拆成 sm_x FLOAT, sm_y FLOAT, sm_z FLOAT 三列
};

// 文件：kbe/src/lib/db_redis/entity_table_redis.h（简化）
// Redis 没有真正的"表"
// 用 Hash 存实体属性：tbl_Account:1 = {name: "foo", level: 10, ...}
// 用 Sorted Set 做索引
// Key 设计：dbname:entityType:entityID:field

// 文件：BigWorld-Engine-14.4.1/programming/bigworld/lib/db_storage_mysql/mappings/property_mapping.hpp（简化）
class PropertyMapping : public SafeReferenceCount
{
public:
    static PropertyMappingPtr create(const Namer& namer,
        const BW::string& propName, const DataType& type,
        int databaseLength, DataSectionPtr pDefaultValue,
        DatabaseIndexingType indexingType);

    virtual void fromStreamToDatabase(StreamToQueryHelper& helper,
        BinaryIStream& strm, QueryRunner& queryRunner) const = 0;
    virtual void fromDatabaseToStream(ResultToStreamHelper& helper,
        ResultStream& results, BinaryOStream& strm) const = 0;
};

// 文件：BigWorld-Engine-14.4.1/programming/bigworld/lib/db_storage_mysql/mappings/entity_type_mapping.hpp（简化）
class EntityTypeMapping : public EntityMapping
{
public:
    DatabaseID getDbID(MySql& connection, const BW::string& name) const;
    bool getName(MySql& connection, DatabaseID dbID, BW::string& name) const;
    bool checkExists(MySql& connection, DatabaseID dbID) const;

    DatabaseID insertNew(MySql& connection, BinaryIStream& strm) const;
    DatabaseID insertExplicit(MySql& connection, DatabaseID dbID,
        BinaryIStream& strm) const;
    bool update(MySql& connection, DatabaseID dbID,
        BinaryIStream& strm, GameTime* pGameTime) const;
    bool getStreamByID(MySql& connection, DatabaseID dbID,
        BinaryOStream& strm) const;
    bool deleteWithID(MySql& connection, DatabaseID dbID) const;
};

// KBEngine EntityTable 中的 auto-load 逻辑
void EntityTable::queryAutoLoadEntities(DBInterface* pdbi,
    ScriptDefModule* pModule, ENTITY_ID start, ENTITY_ID end,
    std::vector<DBID>& outs);

// 统一接口
class DBInterface
{
    virtual bool query(const char* strCommand, uint32 size, ...) = 0;
    virtual EntityTable* createEntityTable(EntityTables* pEntityTables) = 0;
    virtual bool dropEntityTableFromDB(const char* tableName) = 0;
};