/* sp-ul_db module
 *
 * Copyright (C) 2007 1&1 Internet AG
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * Kamailio 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 of the License, or
 * (at your option) any later version
 *
 * Kamailio 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "ul_db_query.h"
#include "ul_db.h"


static int order_dbs(ul_db_handle_t *handle, int order[]);

static int db_exec_query(db_func_t *dbf, db1_con_t *dbh, str *table,
		db_key_t *_k, db_op_t *_op, db_val_t *_v, db_key_t *_c, int _n, int _nc,
		db_key_t _o, db1_res_t **_r);

int db_query(ul_db_handle_t *handle, db1_con_t ***_r_h, db_func_t **_r_f,
		str *table, db_key_t *_k, db_op_t *_op, db_val_t *_v, db_key_t *_c,
		int _n, int _nc, db_key_t _o, db1_res_t **_r, int rw)
{
	int order[DB_NUM];
	int i;
	int err[DB_NUM];
	int ret = -1;

	if(!handle || !table || !table->s || !_r_h) {
		LM_ERR("NULL pointer in parameter.\n");
		return -1;
	}

	order_dbs(handle, order);
	memset(err, 0, sizeof(int) * DB_NUM);

	i = 0;
	do {
		LM_DBG("now trying id %i, db %i.\n", handle->id,
				handle->db[order[i]].no);
		if(handle->db[order[i]].status == DB_ON) {
			if((ret = db_exec_query(&handle->db[order[i]].dbf,
						handle->db[order[i]].dbh, table, _k, _op, _v, _c, _n,
						_nc, _o, _r))
					< 0) {
				LM_ERR("could not query table %.*s error on id %i, db %i.\n",
						table->len, table->s, handle->id,
						handle->db[order[i]].no);
				if(rw) {
					if(err[i] == 0 && handle->db[order[i]].status == DB_ON) {
						if(db_handle_error(handle, handle->db[order[i]].no)
								< 0) {
							LM_ERR("could not handle error on id %i, db %i.\n",
									handle->id, handle->db[order[i]].no);
						} else {
							err[i] = 1;
							i--;
						}
					}
				}
			}
		}
		i++;
	} while((ret < 0) && (i < DB_NUM));
	i--;
	LM_DBG("returned handle is for id %i, db %i\n", handle->id,
			handle->db[order[i]].no);
	*_r_h = &handle->db[order[i]].dbh;
	*_r_f = &handle->db[order[i]].dbf;
	return ret;
}

static int order_dbs(ul_db_handle_t *handle, int order[])
{
	int i, j, tmp;
	for(i = 0; i < DB_NUM; i++) {
		order[i] = i;
	}
	for(i = 0; i < DB_NUM; i++) {
		for(j = i + 1; j < DB_NUM; j++) {
			if((handle->db[i].status == DB_OFF
					   || handle->db[i].status == DB_INACTIVE)
					&& (handle->db[j].status == DB_ON)) {
				tmp = order[i];
				order[i] = order[j];
				order[j] = tmp;
			} else if(handle->db[i].failover_time
					  > handle->db[j].failover_time) {
				tmp = order[i];
				order[i] = order[j];
				order[j] = tmp;
			}
		}
	}
	return 0;
}

static int db_exec_query(db_func_t *dbf, db1_con_t *dbh, str *table,
		db_key_t *_k, db_op_t *_op, db_val_t *_v, db_key_t *_c, int _n, int _nc,
		db_key_t _o, db1_res_t **_r)
{
	if(!dbf || !dbh || !table || !table->s) {
		LM_ERR("NULL pointer in parameter.\n");
		return -1;
	}
	if(dbf->use_table(dbh, table) < 0) {
		LM_ERR("could not use table %.*s.\n", table->len, table->s);
		return -1;
	}
	if(dbf->query(dbh, _k, _op, _v, _c, _n, _nc, _o, _r) < 0) {
		LM_ERR("could not query table %.*s.\n", table->len, table->s);
		return -1;
	}
	return 0;
}
