// Copyright (C) 2021 The Android Open Source Project
//
// 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 <sys/types.h>

#include <cstdint>
#include <memory>
#include <random>
#include <vector>

#include <ditto/instruction.h>

namespace dittosuite {

class ReadWriteFile : public Instruction {
 public:
  explicit ReadWriteFile(SyscallInterface& syscall, const std::string& name, int repeat,
                         int64_t size, int64_t block_size, int64_t starting_offset,
                         Order access_order, uint32_t seed, Reseeding reseeding, int input_fd_key);
  std::unique_ptr<Result> CollectResults(const std::string& prefix) override;

 protected:
  virtual void SetUpSingle() override;
  virtual void RunSingle() override;
  void TearDownSingle() override;

  BandwidthSampler bandwidth_sampler_;
  int64_t size_;
  int64_t block_size_;
  int64_t starting_offset_;
  Order access_order_;
  std::mt19937_64 gen_;
  uint64_t seed_;
  Reseeding reseeding_;
  int input_fd_key_;
  bool update_size_;
  bool update_block_size_;

  struct Unit {
    int64_t count;
    int64_t offset;
  };

  std::vector<Unit> units_;
  std::unique_ptr<char[]> buffer_;

 private:
  void SetUp() override;
};

class WriteFile : public ReadWriteFile {
 public:
  inline static const std::string kName = "write_file";

  explicit WriteFile(SyscallInterface& syscall, int repeat, int64_t size, int64_t block_size,
                     int64_t starting_offset, Order access_order, uint32_t seed,
                     Reseeding reseeding, bool fsync, int input_fd_key);

 private:
  void RunSingle() override;

  bool fsync_;
};

class ReadFile : public ReadWriteFile {
 public:
  inline static const std::string kName = "read_file";

  explicit ReadFile(SyscallInterface& syscall, int repeat, int64_t size, int64_t block_size,
                    int64_t starting_offset, Order access_order, uint32_t seed, Reseeding reseeding,
                    int fadvise, int input_fd_key);

 private:
  void SetUpSingle() override;
  void RunSingle() override;

  int fadvise_;
};

}  // namespace dittosuite