/* ============================================================
 *
 * This file is a part of digiKam project
 * http://www.digikam.org
 *
 * Date        : 2004-06-18
 * Description : SQlite version 2 database interface.
 * 
 * Copyright (C) 2004 by Renchi Raju <renchi@pooh.tam.uiuc.edu>

 * 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 2, 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.
 * 
 * ============================================================ */

// C Ansi includes.

extern "C"
{
#include <sqlite.h>
#include <sys/time.h>
}

// C++ includes.

#include <ctime>
#include <cstdio>
#include <cstdlib>

// TQt includes.

#include <tqfile.h>

// Local includes.

#include "ddebug.h"
#include "albumdb_sqlite2.h"

namespace Digikam
{

typedef struct sqlite_vm sqlite_vm;

AlbumDB_Sqlite2::AlbumDB_Sqlite2()
{
    m_db    = 0;
    m_valid = false;
}

AlbumDB_Sqlite2::~AlbumDB_Sqlite2()
{
    if (m_db) {
        sqlite_close(m_db);
    }
}

void AlbumDB_Sqlite2::setDBPath(const TQString& path)
{
    if (m_db) {
        sqlite_close(m_db);
    m_db = 0;
        m_valid = false;
    }

    char *errMsg = 0;
    m_db = sqlite_open(TQFile::encodeName(path), 0, &errMsg);
    if (m_db == 0)
    {
        DWarning() << k_funcinfo << "Cannot open database: "
                    << errMsg << endl;
        free(errMsg);
        return;
    }

    TQStringList values;
    execSql("SELECT * FROM sqlite_master", &values);
    m_valid = values.contains("Albums");
}

bool AlbumDB_Sqlite2::execSql(const TQString& sql, TQStringList* const values,
                      const bool debug)
{
    if ( debug )
        DDebug() << "SQL-query: " << sql << endl;

    if ( !m_db ) {
        DWarning() << k_funcinfo << "SQLite pointer == NULL"
                    << endl;
        return false;
    }

    const char* tail;
    sqlite_vm* vm;
    char* errorStr;
    int error;
    
    //compile SQL program to virtual machine
    error = sqlite_compile( m_db, sql.local8Bit(), &tail, &vm, &errorStr );

    if ( error != SQLITE_OK ) {
        DWarning() << k_funcinfo << "sqlite_compile error: "
                    << errorStr 
                    << " on query: " << sql << endl;
        sqlite_freemem( errorStr );
        return false;
    }

    int number;
    const char** value;
    const char** colName;
    //execute virtual machine by iterating over rows
    while ( true ) {
        error = sqlite_step( vm, &number, &value, &colName );
        if ( error == SQLITE_DONE || error == SQLITE_ERROR )
            break;
        //iterate over columns
        for ( int i = 0; values && i < number; i++ ) {
            *values << TQString::fromLocal8Bit( value [i] );
        }
    }
    
    //deallocate vm resources
    sqlite_finalize( vm, &errorStr );

    if ( error != SQLITE_DONE ) {
        DWarning() << k_funcinfo << "sqlite_step error: "
                    << errorStr
                    << " on query: " << sql << endl;
        return false;
    }

    return true;
}

}  // namespace Digikam