/*
 *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef WEBRTC_CALL_RTP_RTCP_DEMUXER_HELPER_H_
#define WEBRTC_CALL_RTP_RTCP_DEMUXER_HELPER_H_

#include <algorithm>
#include <map>
#include <utility>

#include "webrtc/api/array_view.h"
#include "webrtc/api/optional.h"
#include "webrtc/rtc_base/basictypes.h"

namespace webrtc {

// TODO(eladalon): Remove this in the next CL.
template <typename Container>
bool MultimapAssociationExists(const Container& multimap,
                               const typename Container::key_type& key,
                               const typename Container::mapped_type& val) {
  auto it_range = multimap.equal_range(key);
  using Reference = typename Container::const_reference;
  return std::any_of(it_range.first, it_range.second,
                     [val](Reference elem) { return elem.second == val; });
}

template <typename Container, typename Value>
size_t RemoveFromMultimapByValue(Container* multimap, const Value& value) {
  size_t count = 0;
  for (auto it = multimap->begin(); it != multimap->end();) {
    if (it->second == value) {
      it = multimap->erase(it);
      ++count;
    } else {
      ++it;
    }
  }
  return count;
}

template <typename Map, typename Value>
size_t RemoveFromMapByValue(Map* map, const Value& value) {
  size_t count = 0;
  for (auto it = map->begin(); it != map->end();) {
    if (it->second == value) {
      it = map->erase(it);
      ++count;
    } else {
      ++it;
    }
  }
  return count;
}

template <typename Container, typename Key>
bool ContainerHasKey(const Container& c, const Key& k) {
  return std::find(c.cbegin(), c.cend(), k) != c.cend();
}

// TODO(eladalon): Remove this in the next CL.
template <typename Container>
bool MultimapHasValue(const Container& c,
                      const typename Container::mapped_type& v) {
  auto predicate = [v](const typename Container::value_type& it) {
    return it.second == v;
  };
  return std::any_of(c.cbegin(), c.cend(), predicate);
}

template <typename Map>
bool MapHasValue(const Map& map, const typename Map::mapped_type& value) {
  auto predicate = [value](const typename Map::value_type& it) {
    return it.second == value;
  };
  return std::any_of(map.cbegin(), map.cend(), predicate);
}

template <typename Container>
bool MultimapHasKey(const Container& c,
                    const typename Container::key_type& key) {
  auto it_range = c.equal_range(key);
  return it_range.first != it_range.second;
}

rtc::Optional<uint32_t> ParseRtcpPacketSenderSsrc(
    rtc::ArrayView<const uint8_t> packet);

}  // namespace webrtc

#endif  // WEBRTC_CALL_RTP_RTCP_DEMUXER_HELPER_H_