//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: Sql wrapper, encapsulates basic SQL functionality
//
// $NoKeywords: $
//=============================================================================
#ifndef ISQLWRAPPER_H
#define ISQLWRAPPER_H

#include "tier0/platform.h"

#ifdef _WIN32
#pragma once
#endif

// SQL column types
enum EColumnType {
    SQL_NONE = 0,
    SQL_INT,
    SQL_STRING,
    SQL_FLOAT,
    SQL_TIME,
    SQL_UINT64
};

//-----------------------------------------------------------------------------
// encapsulates a table's description
//-----------------------------------------------------------------------------
class ISQLTable {
   public:
    virtual int GetCSQLColumn() const = 0;
    virtual const char *PchColumnName(int iSQLColumn) const = 0;
    virtual EColumnType GetEColumnType(int iSQLColumn) const = 0;
    virtual const char *PchName() const = 0;
};

//-----------------------------------------------------------------------------
// encapsulates a database worth of tables
//-----------------------------------------------------------------------------
class ISQLTableSet {
   public:
    virtual int GetCSQLTable() const = 0;
    virtual const ISQLTable *PSQLTable(int iSQLTable) const = 0;
};

//-----------------------------------------------------------------------------
// encapsulates a single returned row from a valid SQL query
//-----------------------------------------------------------------------------
class ISQLRow {
   public:
    virtual int GetCSQLRowData() const = 0;
    virtual const char *PchData(int iSQLColumn) const = 0;
    virtual int NData(int iSQLColumn) const = 0;
    virtual uint64 UlData(int iSQLColumn) const = 0;
    virtual float FlData(int iSQLColumn) const = 0;
    virtual uint64 UlTime(int iSQLColumn) const = 0;
    virtual bool BData(int iSQLColumn) const = 0;
    virtual EColumnType GetEColumnType(int iSQLColumn) const = 0;
};

//-----------------------------------------------------------------------------
// encapsulates a result set, which is made up of a series of rows
// You need to call PNextResult() NRow() times to get all the results
// (there is no random access to the result set).
//-----------------------------------------------------------------------------
class IResultSet {
   public:
    virtual int GetCSQLRow() const = 0;
    virtual const ISQLRow *
    PSQLRowNextResult() = 0;  // note, not const on the class because it makes a
                              // new row object
};

//-----------------------------------------------------------------------------
// This interface encapsulates a database connection and lets you operate on it.
// Use the ISQLWrapperFactory factory to get access to the interface.
// NOTE - you can only have one outstanding query at a time. When you are done
// with a query call FreeResult()
//-----------------------------------------------------------------------------
class ISQLWrapper {
   public:
    // run a SQL statement against the DB, typically an insert statement as no
    // data is returned
    virtual bool BInsert(const char *pchQueryString) = 0;
    // get a description of the tables associated with the db you connected to
    virtual const ISQLTableSet *PSQLTableSetDescription() = 0;
    // run a query against the db and then iterate the result set (you can only
    // have 1 outstanding query at a time, and call FreeResults() when you are
    // done)
    virtual IResultSet *PResultSetQuery(const char *pchQueryString) = 0;
    // you MUST call then after you finish with the IResultSet from the above
    // query
    virtual void FreeResult() = 0;
};

//-----------------------------------------------------------------------------
// This is a factory to create objects that let you interact with a MySQL
// database. Make sure you Free() any interfaces you create.
//-----------------------------------------------------------------------------
class ISQLWrapperFactory {
   public:
    // setup details about this db connection
    virtual ISQLWrapper *Create(const char *pchDB, const char *pchHost,
                                const char *pchUsername,
                                const char *pchPassword) = 0;
    virtual void Free(ISQLWrapper *pSQLWrapper) = 0;
};

#define INTERFACEVERSION_ISQLWRAPPER "ISQLWRAPPER001"

#endif  // ISQLWRAPPER_H