// Protocol Buffers - Google's data interchange format
// Copyright 2023 Google LLC.  All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google LLC nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef UPB_MINI_TABLE_ENCODE_INTERNAL_HPP_
#define UPB_MINI_TABLE_ENCODE_INTERNAL_HPP_

#include <string>

#include "upb/base/internal/log2.h"
#include "upb/mini_descriptor/internal/encode.h"

namespace upb {

class MtDataEncoder {
 public:
  MtDataEncoder() : appender_(&encoder_) {}

  bool StartMessage(uint64_t msg_mod) {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_StartMessage(&encoder_, buf, msg_mod);
    });
  }

  bool PutField(upb_FieldType type, uint32_t field_num, uint64_t field_mod) {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_PutField(&encoder_, buf, type, field_num,
                                        field_mod);
    });
  }

  bool StartOneof() {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_StartOneof(&encoder_, buf);
    });
  }

  bool PutOneofField(uint32_t field_num) {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_PutOneofField(&encoder_, buf, field_num);
    });
  }

  bool StartEnum() {
    return appender_(
        [=](char* buf) { return upb_MtDataEncoder_StartEnum(&encoder_, buf); });
  }

  bool PutEnumValue(uint32_t enum_value) {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_PutEnumValue(&encoder_, buf, enum_value);
    });
  }

  bool EndEnum() {
    return appender_(
        [=](char* buf) { return upb_MtDataEncoder_EndEnum(&encoder_, buf); });
  }

  bool EncodeExtension(upb_FieldType type, uint32_t field_num,
                       uint64_t field_mod) {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_EncodeExtension(&encoder_, buf, type, field_num,
                                               field_mod);
    });
  }

  bool EncodeMap(upb_FieldType key_type, upb_FieldType val_type,
                 uint64_t key_mod, uint64_t val_mod) {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_EncodeMap(&encoder_, buf, key_type, val_type,
                                         key_mod, val_mod);
    });
  }

  bool EncodeMessageSet() {
    return appender_([=](char* buf) {
      return upb_MtDataEncoder_EncodeMessageSet(&encoder_, buf);
    });
  }

  const std::string& data() const { return appender_.data(); }

 private:
  class StringAppender {
   public:
    StringAppender(upb_MtDataEncoder* e) { e->end = buf_ + sizeof(buf_); }

    template <class T>
    bool operator()(T&& func) {
      char* end = func(buf_);
      if (!end) return false;
      // C++ does not guarantee that string has doubling growth behavior, but
      // we need it to avoid O(n^2).
      str_.reserve(upb_Log2CeilingSize(str_.size() + (end - buf_)));
      str_.append(buf_, end - buf_);
      return true;
    }

    const std::string& data() const { return str_; }

   private:
    char buf_[kUpb_MtDataEncoder_MinSize];
    std::string str_;
  };

  upb_MtDataEncoder encoder_;
  StringAppender appender_;
};

}  // namespace upb

#endif /* UPB_MINI_TABLE_ENCODE_INTERNAL_HPP_ */