/*
   This file is part of GNUnet
   Copyright (C) 2017 GNUnet e.V.

   GNUnet is free software: you can redistribute it and/or modify it
   under the terms of the GNU Affero General Public License as published
   by the Free Software Foundation, either version 3 of the License,
   or (at your option) any later version.

   GNUnet 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
   Affero General Public License for more details.

   You should have received a copy of the GNU Affero General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */
/**
 * @file pq/pq_prepare.c
 * @brief functions to connect to libpq (PostGres)
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_pq_lib.h"


/**
 * Create a `struct GNUNET_PQ_PreparedStatement`.
 *
 * @param name name of the statement
 * @param sql actual SQL statement
 * @param num_args number of arguments in the statement
 * @return initialized struct
 */
struct GNUNET_PQ_PreparedStatement
GNUNET_PQ_make_prepare(const char *name,
                       const char *sql,
                       unsigned int num_args)
{
  struct GNUNET_PQ_PreparedStatement ps = {
    .name = name,
    .sql = sql,
    .num_arguments = num_args
  };

  return ps;
}


/**
 * Request creation of prepared statements @a ps from Postgres.
 *
 * @param connection connection to prepare the statements for
 * @param ps #GNUNET_PQ_PREPARED_STATEMENT_END-terminated array of prepared
 *            statements.
 * @return #GNUNET_OK on success,
 *         #GNUNET_SYSERR on error
 */
int
GNUNET_PQ_prepare_statements(PGconn *connection,
                             const struct GNUNET_PQ_PreparedStatement *ps)
{
  for (unsigned int i = 0; NULL != ps[i].name; i++)
    {
      PGresult *ret;

      GNUNET_log_from(GNUNET_ERROR_TYPE_DEBUG,
                      "pq",
                      "Preparing SQL statement `%s' as `%s'\n",
                      ps[i].sql,
                      ps[i].name);
      ret = PQprepare(connection,
                      ps[i].name,
                      ps[i].sql,
                      ps[i].num_arguments,
                      NULL);
      if (PGRES_COMMAND_OK != PQresultStatus(ret))
        {
          GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
                          "pq",
                          _("PQprepare (`%s' as `%s') failed with error: %s\n"),
                          ps[i].sql,
                          ps[i].name,
                          PQerrorMessage(connection));
          PQclear(ret);
          return GNUNET_SYSERR;
        }
      PQclear(ret);
    }
  return GNUNET_OK;
}


/* end of pq/pq_prepare.c */