/*
   This file is part of TALER
   Copyright (C) 2025 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/merchant-database/iterate_statistic_bucket_counters_by_range.h
 * @brief implementation of the iterate_statistic_bucket_counters_by_range function for Postgres
 * @author Christian Grothoff
 */
#ifndef MERCHANT_DATABASE_ITERATE_STATISTIC_BUCKET_COUNTERS_BY_RANGE_H
#define MERCHANT_DATABASE_ITERATE_STATISTIC_BUCKET_COUNTERS_BY_RANGE_H

#include <taler/taler_util.h>
#include <taler/taler_json_lib.h>
#include "merchantdb_lib.h"


/**
 * Function returning integer-valued statistics for a bucket.
 * Called by `iterate_statistic_bucket_counters_by_range`.
 *
 * @param cls closure
 * @param bucket_start start time of the bucket
 * @param counters_len the length of @a cumulative_amounts
 * @param descriptions description for the counter in the bucket
 * @param counters the counters in the bucket
 */
typedef void
(*TALER_MERCHANTDB_CounterByBucketRangeStatisticsCallback)(
  void *cls,
  struct GNUNET_TIME_Timestamp bucket_start,
  unsigned int counters_len,
  const char *descriptions[static counters_len],
  uint64_t counters[static counters_len]);


/**
 * Lookup counter statistics for instance and slug-prefix by bucket.
 *
 * @param pg database context
 * @param instance_id instance to lookup statistics for
 * @param prefix slug prefix to lookup statistics under
 * @param granularity limit to buckets of this size
 * @param counter requested number of buckets
 * @param cb function to call on all token families found
 * @param cb_cls closure for @a cb
 * @return database result code
 */
enum GNUNET_DB_QueryStatus
TALER_MERCHANTDB_iterate_statistic_bucket_counters_by_range (
  struct TALER_MERCHANTDB_PostgresContext *pg,
  const char *instance_id,
  const char *prefix,
  const char *granularity,
  uint64_t counter,
  TALER_MERCHANTDB_CounterByBucketRangeStatisticsCallback cb,
  void *cb_cls);


#endif
