// Copyright 2019 The MediaPipe Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef MEDIAPIPE_FRAMEWORK_TOOL_OPTIONS_UTIL_H_
#define MEDIAPIPE_FRAMEWORK_TOOL_OPTIONS_UTIL_H_

#include "mediapipe/framework/calculator.pb.h"
#include "mediapipe/framework/input_stream_shard.h"
#include "mediapipe/framework/packet.h"
#include "mediapipe/framework/packet_set.h"
#include "mediapipe/framework/port/any_proto.h"
#include "mediapipe/framework/tool/options_map.h"
#include "mediapipe/framework/tool/type_util.h"

namespace mediapipe {

namespace tool {

// Combine a base options with an overriding options.
template <typename T>
inline T MergeOptions(const T& base, const T& options) {
  auto result = base;
  result.MergeFrom(options);
  return result;
}

// Combine a base options message with an optional side packet. The specified
// packet can hold either the specified options type T or CalculatorOptions.
// Fields are either replaced or merged depending on field merge_fields.
template <typename T>
inline T RetrieveOptions(const T& base, const Packet& options_packet) {
  if (!options_packet.IsEmpty()) {
    T packet_options;
    if (options_packet.ValidateAsType<T>().ok()) {
      packet_options = options_packet.Get<T>();
    } else if (options_packet.ValidateAsType<CalculatorOptions>().ok()) {
      GetExtension<T>(options_packet.Get<CalculatorOptions>(), &packet_options);
    }
    return tool::MergeOptions(base, packet_options);
  }
  return base;
}

// Combine a base options message with an optional side packet from
// a PacketSet such as a calculator's input-side-packets.
template <typename T>
inline T RetrieveOptions(const T& base, const PacketSet& packet_set,
                         const std::string& tag_name = "OPTIONS") {
  if (packet_set.HasTag(tag_name)) {
    return tool::RetrieveOptions(base, packet_set.Tag(tag_name));
  }
  return base;
}

// Combine a base options message with an optional input packet from
// an InputStreamShardSet such as a calculator's input streams.
template <typename T>
inline T RetrieveOptions(const T& base, const InputStreamShardSet& stream_set,
                         const std::string& tag_name = "OPTIONS") {
  if (stream_set.HasTag(tag_name)) {
    Packet options_packet = stream_set.Tag(tag_name).Value();
    return tool::RetrieveOptions(base, options_packet);
  }
  return base;
}

// Finds the descriptor for a protobuf.
const proto_ns::Descriptor* GetProtobufDescriptor(const std::string& type_name);

}  // namespace tool
}  // namespace mediapipe

#endif  // MEDIAPIPE_FRAMEWORK_TOOL_OPTIONS_UTIL_H_