/* 
*
*  ProLinga-Data
*
*  Copyright (C) 2002-2009 Xobas Software.
*  All rights reserved.
*  
*  This file is part of ProLinga-Data.
*
*  ProLinga-Data 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.
*
*  ProLinga-Data 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 ProLinga-Data.  If not, see <http://www.gnu.org/licenses/>.
*
*  More information is available at the following addresses:
*
*  Website     : http://www.prolinga.org
*
*  Email       : prolinga-list@prolinga.org
*
*
*/
#include "DatCommon.h"
#include <libxml/xmlmemory.h>
#include <libxml/parser.h>
#include <libxml/xpath.h>
#include <libgda/libgda.h>
#include "DatMain.hpp"
#include "DCDataSource.hpp"
#include "DCExecuteQuery.hpp"
#include "ExecuteSql.hpp"
#include "DCSession.hpp"
#include "DatConfig.hpp"

extern DCSessionPtr sesPtr;


int DCExecuteQuery(const xmlDocPtr docObj, const char *sessionId, char **externalError, xmlDocPtr *docReturn)
{
	xmlNodePtr curReturn, curTmp;
	xmlXPathContextPtr ctxObj;
	xmlXPathObjectPtr resObj;
	GdaConnection *connection;
	GdaDataModel *dm;
	GdaColumn *fa;
        gint rowId;
        gint columnId;
        GValue *value;
	char *objDataSource, *sqlBuffer, tmpString[255];

	/* Create XPath Environment */
	ctxObj = xmlXPathNewContext(docObj);

	/* Get DataSource name */
	resObj = xmlXPathEval((const xmlChar *)"/ProLinga/Object/@DataSource", ctxObj);
	objDataSource = (char *)xmlXPathCastToString(resObj);

	/* Get Connection Object to Data Source */
	connection = sesPtr->getGdaConnection(sesPtr, sessionId, objDataSource);
	if (connection == NULL)
		return 70002;

	/* Get SQL statement */
	resObj = xmlXPathEval((const xmlChar *)"/ProLinga/Object/Query/Sql", ctxObj);
	sqlBuffer = new char[(strlen((char *)xmlXPathCastToString(resObj))+1)];
	strcpy(sqlBuffer, (char *)xmlXPathCastToString(resObj));

	/* Execute Statement */
	dm = ExecuteSqlSingleCommand(connection, sqlBuffer, sesPtr, sessionId);
	if (dm == NULL)
	{
		delete sqlBuffer;
		*externalError = ConnectionError(connection);
		return 90001;
	}

	/* No longer needed */
	delete sqlBuffer;

	/* Create return document */
	*docReturn = xmlNewDoc((const xmlChar *)XML_VERSION);
	(*docReturn)->children = xmlNewDocNode(*docReturn, NULL, (const xmlChar *)ROOT_ELEM, NULL);
	curReturn = xmlDocGetRootElement(*docReturn);
	curReturn = xmlNewTextChild(curReturn, NULL, (const xmlChar *)"Object", (const xmlChar *)"");
	xmlNewProp(curReturn, (const xmlChar *)"DataSource", (const xmlChar *)objDataSource);
	curReturn = xmlNewTextChild(curReturn, NULL, (const xmlChar *)"Query", (const xmlChar *)"");
	curReturn = xmlNewTextChild(curReturn, NULL, (const xmlChar *)"Result", (const xmlChar *)"");

	/* Get Column Headers */
	curTmp = xmlNewTextChild(curReturn, NULL, (const xmlChar *)"ColumnHeaderInstances", (const xmlChar *)"");

        for (columnId = 0; columnId < gda_data_model_get_n_columns(dm); columnId++)
	{
		/* Get Field Attributes */
		fa = gda_data_model_describe_column(dm, columnId);

		curTmp = xmlNewTextChild(curTmp, NULL, (const xmlChar *)"ColumnHeaderInstance", (const xmlChar *)"");
		sprintf(tmpString, "%d", columnId + 1);
		xmlNewProp(curTmp, (const xmlChar *)"SequenceNo", (const xmlChar *)tmpString);
		xmlNewProp(curTmp, (const xmlChar *)"Name", (const xmlChar *)gda_data_model_get_column_title(dm, columnId));
		xmlNewProp(curTmp, (const xmlChar *)"StorageType", (const xmlChar *)gda_g_type_to_string (gda_column_get_g_type (fa)));
//		sprintf(tmpString, "%ld", gda_column_get_defined_size(fa));
//		sprintf(tmpString, "%ld", fa->priv->defined_size);
//		xmlNewProp(curTmp, (const xmlChar *)"Size", (const xmlChar *)tmpString);
//		sprintf(tmpString, "%ld", gda_column_get_scale(fa));
//		xmlNewProp(curTmp, (const xmlChar *)"Decimals", (const xmlChar *)tmpString);
//		xmlNewProp(curTmp, (const xmlChar *)"Decimals", (const xmlChar *)gda_value_stringify (gda_column_get_attribute (fa, GDA_ATTRIBUTE_NUMERIC_SCALE)));
		curTmp = curTmp->parent;

		//g_object_unref(fa);
	}
	
	/* Get Data  */
	curTmp = xmlNewTextChild(curReturn, NULL, (const xmlChar *)"DataInstances", (const xmlChar *)"");
	
        for (rowId = 0; rowId < gda_data_model_get_n_rows(dm); rowId++)
        {
		curTmp = xmlNewTextChild(curTmp, NULL, (const xmlChar *)"DataInstance", (const xmlChar *)"");
		sprintf(tmpString, "%d", rowId + 1);
		xmlNewProp(curTmp, (const xmlChar *)"SequenceNo", (const xmlChar *)tmpString);

                for (columnId = 0; columnId < gda_data_model_get_n_columns(dm); columnId++)
                {
                        value = (GValue *) gda_data_model_get_value_at(dm, columnId, rowId, NULL);
			xmlNewTextChild(curTmp, NULL, (const xmlChar *)gda_data_model_get_column_title(dm, columnId), (const xmlChar *)gda_value_stringify (value));
                }
		curTmp = curTmp->parent;
        }

	/* Clean up */
	g_object_unref(dm);

	/* Return */	
	return 0;
}