/* GNOME DB ORACLE Provider
 * Copyright (C) 2000 Rodrigo Moya
 * Copyright (C) 2000 Stephan Heinze
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "gda-oracle.h"

#define ORA_NAME_BUFFER_SIZE 30

/*
 * Private functions
 */
static GdaServerRecordset *
init_recordset_fields (GdaServerRecordset * recset,
		       ORACLE_Recordset * ora_recset,
		       ORACLE_Command * ora_cmd, GdaError * error)
{
	g_return_val_if_fail (recset != NULL, recset);
	g_return_val_if_fail (ora_recset != NULL, recset);
	g_return_val_if_fail (ora_cmd != NULL, recset);
	g_return_val_if_fail (ora_cmd->hstmt == ora_recset->hstmt, recset);

	/* traverse all fields in resultset */
	if (ora_cmd->stmt_type == OCI_STMT_SELECT) {
		gint counter = 1;
		OCIParam *param;
		sb4 param_status;

		param_status = OCIParamGet (ora_recset->hstmt,
					    OCI_HTYPE_STMT,
					    ora_recset->ora_cnc->herr,
					    (dvoid **) & param,
					    (ub4) counter);
		while (param_status == OCI_SUCCESS) {
			glong col_name_len;
			gchar name_buffer[ORA_NAME_BUFFER_SIZE + 1];
			gchar *pgchar_dummy;
			GdaServerField *field;
			ORACLE_Field *ora_field;

			field = gda_server_field_new ();
			/* associate private structure with field */
			ora_field = g_new0 (ORACLE_Field, 1);
			gda_server_field_set_user_data (field,
							(gpointer) ora_field);

			/* fill in field information */
			/* attention - names are not terminated by '\0' */
			OCIAttrGet ((dvoid *) param,
				    OCI_DTYPE_PARAM,
				    &pgchar_dummy,
				    (ub4) & col_name_len,
				    OCI_ATTR_NAME, ora_recset->ora_cnc->herr);
			memcpy (name_buffer, pgchar_dummy, col_name_len);
			name_buffer[col_name_len] = '\0';
			gda_server_field_set_name (field, name_buffer);

			OCIAttrGet ((dvoid *) param,
				    OCI_DTYPE_PARAM,
				    &(field->sql_type),
				    0,
				    OCI_ATTR_DATA_TYPE,
				    ora_recset->ora_cnc->herr);

			/* wanna get numeric as string (TO BE FIXED) */
			if (SQLT_NUM == field->sql_type ||
			    SQLT_VNU == field->sql_type) {
				field->sql_type = SQLT_AVC;
			}
			OCIAttrGet ((dvoid *) param,
				    OCI_DTYPE_PARAM,
				    &(field->nullable),
				    0,
				    OCI_ATTR_IS_NULL,
				    ora_recset->ora_cnc->herr);
			OCIAttrGet ((dvoid *) param,
				    OCI_DTYPE_PARAM,
				    &(field->precision),
				    0,
				    OCI_ATTR_PRECISION,
				    ora_recset->ora_cnc->herr);
			OCIAttrGet ((dvoid *) param,
				    OCI_DTYPE_PARAM,
				    &(field->num_scale),
				    0,
				    OCI_ATTR_SCALE,
				    ora_recset->ora_cnc->herr);
			OCIAttrGet ((dvoid *) param,
				    OCI_DTYPE_PARAM,
				    &(field->defined_length),
				    0,
				    OCI_ATTR_DATA_SIZE,
				    ora_recset->ora_cnc->herr);
			gda_server_field_set_actual_length (field, 0);

			/* bind output columns to 'ora_field->real_value' */
			ora_field->real_value =
				g_malloc0 (field->defined_length);
			ora_field->hdef = NULL;
			ora_field->indicator = 0;
			if (OCIDefineByPos (ora_recset->hstmt,
					    &ora_field->hdef,
					    ora_recset->ora_cnc->herr,
					    counter,
					    ora_field->real_value,
					    field->defined_length,
					    field->sql_type,
					    &ora_field->indicator,
					    0,
					    0, OCI_DEFAULT) != OCI_SUCCESS) {
				gda_server_error_make (error,
						       0,
						       gda_server_recordset_get_connection
						       (recset),
						       __PRETTY_FUNCTION__);
				return recset;
			}

			/* add field to GdaServerRecordset structure */
			gda_server_recordset_add_field (recset, field);

			/* retrieve next field */
			counter++;
			param_status = OCIParamGet (ora_recset->hstmt,
						    OCI_HTYPE_STMT,
						    ora_recset->ora_cnc->herr,
						    (dvoid **) & param,
						    (ub4) counter);
		}

		/* if param_status != OCI_NO_DATA, there was an error */
		if (param_status != OCI_NO_DATA) {
			gda_server_error_make (error,
					       0,
					       gda_server_recordset_get_connection
					       (recset), __PRETTY_FUNCTION__);
		}
	}
	return recset;
}

/*
 * Public functions
 */
gboolean
gda_oracle_command_new (GdaServerCommand * cmd)
{
	ORACLE_Command *ora_cmd;
	GdaServerConnection *cnc;
	ORACLE_Connection *ora_cnc;

	g_return_val_if_fail (cmd != NULL, FALSE);

	ora_cmd = g_new0 (ORACLE_Command, 1);
	gda_server_command_set_user_data (cmd, (gpointer) ora_cmd);

	cnc = gda_server_command_get_connection (cmd);
	if (cnc) {
		ora_cnc =
			(ORACLE_Connection *)
			gda_server_connection_get_user_data (cnc);
		ora_cmd->ora_cnc = ora_cnc;

		/* initialize Oracle command */
		if (OCI_SUCCESS !=
		    OCIHandleAlloc ((CONST dvoid *) ora_cmd->ora_cnc->henv,
				    (dvoid **) & ora_cmd->hstmt,
				    OCI_HTYPE_STMT, (size_t) 0,
				    (dvoid **) NULL)) {
			GdaError *error = gda_error_new ();
			gda_server_error_make (error,
					       0,
					       gda_server_command_get_connection
					       (cmd), __PRETTY_FUNCTION__);
			gda_error_set_description (error,
						   _
						   ("Could not allocate statement handle"));
			return FALSE;
		}
	}
	else
		gda_log_message (_
				 ("command object being created without associated connection"));
	return TRUE;
}

GdaServerRecordset *
gda_oracle_command_execute (GdaServerCommand * cmd,
			    GdaError * error,
			    const GDA_CmdParameterSeq * params,
			    gulong * affected, gulong options)
{
	GdaServerRecordset *recset = NULL;

	/* create recordset to be returned */
	recset = gda_server_recordset_new (gda_server_command_get_connection
					   (cmd));
	if (recset) {
		ORACLE_Command *ora_cmd;
		ORACLE_Recordset *ora_recset;
		gchar *cmd_text;

		/* get each object's private data */
		ora_cmd =
			(ORACLE_Command *)
			gda_server_command_get_user_data (cmd);
		ora_recset =
			(ORACLE_Recordset *)
			gda_server_recordset_get_user_data (recset);
		if (ora_cmd && ora_recset) {
			switch (gda_server_command_get_cmd_type (cmd)) {
			case GDA_COMMAND_TYPE_TABLE:{
					gchar *tmp =
						g_strdup_printf
						("SELECT * FROM %s",
						 gda_server_command_get_text
						 (cmd));
					gda_server_command_set_text (cmd,
								     tmp);
					g_free ((gpointer) tmp);
				}
			case GDA_COMMAND_TYPE_TEXT:
				cmd_text = gda_server_command_get_text (cmd);
				gda_log_message (_("Executing command '%s'"),
						 cmd_text);

				if (OCI_SUCCESS ==
				    OCIStmtPrepare (ora_cmd->hstmt,
						    ora_cmd->ora_cnc->herr,
						    (CONST text *) cmd_text,
						    strlen (cmd_text),
						    OCI_NTV_SYNTAX,
						    OCI_DEFAULT)) {
					ora_cmd->stmt_type = 0;
					OCIAttrGet ((dvoid *) ora_cmd->hstmt,
						    OCI_HTYPE_STMT,
						    (dvoid *) & ora_cmd->
						    stmt_type, NULL,
						    OCI_ATTR_STMT_TYPE,
						    ora_cmd->ora_cnc->herr);

					/* now, really execute the command */
					if (OCI_SUCCESS ==
					    OCIStmtExecute (ora_cmd->ora_cnc->
							    hservice,
							    ora_cmd->hstmt,
							    ora_cmd->ora_cnc->
							    herr,
							    (ub4) ((OCI_STMT_SELECT == ora_cmd->stmt_type) ? 0 : 1), (ub4) 0, (CONST OCISnapshot *) NULL, (OCISnapshot *) NULL, OCI_DEFAULT)) {
						ora_recset->ora_cnc =
							ora_cmd->ora_cnc;
						if (OCI_STMT_SELECT ==
						    ora_cmd->stmt_type) {
							ora_recset->hstmt =
								ora_cmd->
								hstmt;
							return init_recordset_fields (recset, ora_recset, ora_cmd, error);
						}
						else
							return recset;
					}
				}
				gda_server_error_make (error,
						       0,
						       gda_server_command_get_connection
						       (cmd),
						       __PRETTY_FUNCTION__);
				break;
			}
		}

		/* free memory on error */
		gda_server_recordset_free (recset);
		recset = NULL;
	}

	return recset;
}

void
gda_oracle_command_free (GdaServerCommand * cmd)
{
	ORACLE_Command *ora_cmd;

	g_return_if_fail (cmd != NULL);

	ora_cmd = (ORACLE_Command *) gda_server_command_get_user_data (cmd);
	if (ora_cmd) {
		/* free Stmt handle allocated in gda_oracle_command_new() */
		if (ora_cmd->hstmt != NULL)
			OCIHandleFree ((dvoid *) ora_cmd->hstmt,
				       OCI_HTYPE_STMT);
		g_free ((gpointer) ora_cmd);
	}
}