/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * 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.
 */

#pragma once

#include <string>
#include <folly/Range.h>

namespace apache {
namespace thrift {

// This module allows us to take an arbitrary serialized Protocol stream
// and print it to human readable format, without needing the Thrift
// structure definition.
//
// In doing so, we won't be able to render the tag names, but we can
// still provide some useful debugging info, particularly for data
// that might be in an arbitrary table or the result of some computation, e.g.
//
//  toDebugString(protoReader) ->
//    struct {
//      1: string = "image.jpg"
//      2: i32 = 640
//      3: i32 = 480
//      4: float = 0.85
//      5 list<i64> = [
//        2342342343,
//        4353453453,
//      ]
//    }
//
// We provide a few simple rendering options, such as whether newlines
// are wanted (or if putting the data in one line is better), and the
// indent level.
//
// We also provide a reverse fromDebugString() method, to convert from this
// text format to a serialized data stream.
//
// WARNING: you should not store data persistently in this text string format,
// since it's subject to change. Instead prefer the standard Compact/Binary/etc.
// Protocol formats.

struct DebugStringParams {
  bool oneLine{false};
  uint16_t indentAmount{2};
};

// Converts serialized protocol data -> text format
//
// Usage example:
//   apache::thrift::CompactProtocolReader reader;
//   reader.setInput(iobufWithSerializedData);
//   std::cout << apache::thrift::toDebugString(reader);
//
template <class ProtocolReader>
std::string toDebugString(
    ProtocolReader& inProtoReader, DebugStringParams p = {});

// Converts text format -> serialized protocol data
//
// Usage example:
//   folly::IOBufQueue outputQueue;
//   apache::thrift::CompactProtocolWriter writer;
//   writer.setOutput(&outputQueue);
//   apache::thrift::fromDebugString(debugString, writer);
//   auto outputIOBufWithData = outputQueue.move();
//
template <class ProtocolWriter>
void fromDebugString(folly::StringPiece text, ProtocolWriter& outProtoWriter);

} // namespace thrift
} // namespace apache