/*
   This file is part of TALER
   Copyright (C) 2024 Taler Systems SA

   TALER 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, or (at your option) any later version.

   TALER 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
   TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
 */
/**
 * @file src/backenddb/get_category.c
 * @brief Implementation of the get_category function for Postgres
 * @author Christian Grothoff
 */
#include "platform.h"
#include <taler/taler_pq_lib.h>
#include "merchant-database/get_category.h"
#include "helper.h"


enum GNUNET_DB_QueryStatus
TALER_MERCHANTDB_get_category (
  struct TALER_MERCHANTDB_PostgresContext *pg,
  const char *instance_id,
  uint64_t category_id,
  struct TALER_MERCHANTDB_CategoryDetails *cd,
  size_t *num_products,
  char **products)
{
  struct GNUNET_PQ_QueryParam params[] = {
    GNUNET_PQ_query_param_uint64 (&category_id),
    GNUNET_PQ_query_param_end
  };
  struct GNUNET_PQ_ResultSpec rs[] = {
    GNUNET_PQ_result_spec_string ("category_name",
                                  &cd->category_name),
    TALER_PQ_result_spec_json ("category_name_i18n",
                               &cd->category_name_i18n),
    GNUNET_PQ_result_spec_array_string (pg->conn,
                                        "products",
                                        num_products,
                                        products),
    GNUNET_PQ_result_spec_end
  };

  GNUNET_assert (NULL != pg->current_merchant_id);
  GNUNET_assert (0 == strcmp (instance_id,
                              pg->current_merchant_id));
  TMH_PQ_prepare_anon (pg,
                       "SELECT"
                       " category_name"
                       ",category_name_i18n::TEXT"
                       ",t.product_array AS products"
                       " FROM merchant_categories mc"
                       ",LATERAL ("
                       "   SELECT ARRAY ("
                       "     SELECT "
                       "         mi.product_id AS product_id"
                       "       FROM merchant_product_categories mpc"
                       "       JOIN merchant_inventory mi"
                       "          USING (product_serial)"
                       "      WHERE mpc.category_serial = mc.category_serial"
                       "   ) AS product_array"
                       " ) t"
                       " WHERE mc.category_serial=$1");
  return GNUNET_PQ_eval_prepared_singleton_select (
    pg->conn,
    "",
    params,
    rs);
}
