/*
   This file is part of TALER
   Copyright (C) 2022 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/include/exchange-database/do_refund.h
 * @brief implementation of the do_refund function for Postgres
 * @author Christian Grothoff
 */
#ifndef EXCHANGE_DATABASE_DO_REFUND_H
#define EXCHANGE_DATABASE_DO_REFUND_H

#include "taler/taler_util.h"
#include "exchange-database/free_coin_transaction_list.h"

/**
 * @brief Specification for a refund operation.  The combination of
 * the coin's public key, the merchant's public key and the
 * transaction ID must be unique.  While a coin can (theoretically) be
 * deposited at the same merchant twice (with partial spending), the
 * merchant must either use a different public key or a different
 * transaction ID for the two transactions.  The same goes for
 * refunds, hence we also have a "rtransaction" ID which is disjoint
 * from the transaction ID.  The same coin must not be used twice at
 * the same merchant for the same transaction or rtransaction ID.
 */
struct TALER_EXCHANGEDB_Refund
{
  /**
   * Information about the coin that is being refunded.
   */
  struct TALER_CoinPublicInfo coin;

  /**
   * Details about the refund.
   */
  struct TALER_EXCHANGEDB_RefundListEntry details;

};


/**
 * Perform refund operation, checking for sufficient deposits
 * of the coin and possibly persisting the refund details.
 *
 * @param pg the database context
 * @param refund refund operation details
 * @param deposit_fee deposit fee applicable for the coin, possibly refunded
 * @param known_coin_id row of the coin in the known_coins table
 * @param[out] not_found set if the deposit was not found
 * @param[out] refund_ok  set if the refund succeeded (below deposit amount)
 * @param[out] gone if the merchant was already paid
 * @param[out] conflict set if the refund ID was reused
 * @return query execution status
 */
enum GNUNET_DB_QueryStatus
TALER_EXCHANGEDB_do_refund (struct TALER_EXCHANGEDB_PostgresContext *pg,
                            const struct TALER_EXCHANGEDB_Refund *refund,
                            const struct TALER_Amount *deposit_fee,
                            uint64_t known_coin_id,
                            bool *not_found,
                            bool *refund_ok,
                            bool *gone,
                            bool *conflict);

#endif
